Fluke 8588A, 8558A Operator's Manual

8588A/8558A

Reference Multimeter and 8 1/2 Digit Multimeter

February 2019

© 2019 Fluke Corporation. All rights reserved. Specifications are subject to change without notice.
All product names are trademarks of their respective companies.

Operators Manual

LIMITED WARRANTY AND LIMITATION OF LIABILITY

Each Fluke product is warranted to be free from defects in material and workmanship under normal use and
service. The warranty period is one year and begins on the date of shipment. Parts, product repairs, and
services are warranted for 90 days. This warranty extends only to the original buyer or end-user customer of
a Fluke authorized reseller, and does not apply to fuses, disposable batteries, or to any product which, in
Fluke's opinion, has been misused, altered, neglected, contaminated, or damaged by accident or abnormal
conditions of operation or handling. Fluke warrants that software will operate substantially in accordance
with its functional specifications for 90 days and that it has been properly recorded on non-defective media.
Fluke does not warrant that software will be error free or operate without interruption.

Fluke authorized resellers shall extend this warranty on new and unused products to end-user customers
only but have no authority to extend a greater or different warranty on behalf of Fluke. Warranty support is
available only if product is purchased through a Fluke authorized sales outlet or Buyer has paid the
applicable international price. Fluke reserves the right to invoice Buyer for importation costs of
repair/replacement parts when product purchased in one country is submitted for repair in another country.

Fluke's warranty obligation is limited, at Fluke's option, to refund of the purchase price, free of charge repair,
or replacement of a defective product which is returned to a Fluke authorized service center within the
warranty period.

To obtain warranty service, contact your nearest Fluke authorized service center to obtain return
authorization information, then send the product to that service center, with a description of the difficulty,
postage and insurance prepaid (FOB Destination). Fluke assumes no risk for damage in transit. Following
warranty repair, the product will be returned to Buyer, transportation prepaid (FOB Destination). If Fluke
determines that failure was caused by neglect, misuse, contamination, alteration, accident, or abnormal
condition of operation or handling, including overvoltage failures caused by use outside the product’s
specified rating, or normal wear and tear of mechanical components, Fluke will provide an estimate of repair
costs and obtain authorization before commencing the work. Following repair, the product will be returned to
the Buyer transportation prepaid and the Buyer will be billed for the repair and return transportation charges
(FOB Shipping Point).

THIS WARRANTY IS BUYER'S SOLE AND EXCLUSIVE REMEDY AND IS IN LIEU OF ALL OTHER
WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY IMPLIED WARRANTY
OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. FLUKE SHALL NOT BE LIABLE
FOR ANY SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL DAMAGES OR LOSSES,
INCLUDING LOSS OF DATA, ARISING FROM ANY CAUSE OR THEORY.

Since some countries or states do not allow limitation of the term of an implied warranty, or exclusion or
limitation of incidental or consequential damages, the limitations and exclusions of this warranty may not
apply to every buyer. If any provision of this Warranty is held invalid or unenforceable by a court or other
decision-maker of competent jurisdiction, such holding will not affect the validity or enforceability of any other
provision.

Fluke Corporation
P.O. Box 9090
Everett, WA 98206-9090
U.S.A.

Fluke Europe B.V.
P.O. Box 1186
5602 BD Eindhoven
The Netherlands

11/99

Table of Contents

Title Page

Introduction ............................................................................................ 1

Safety Information ................................................................................. 1

Specifications ........................................................................................ 1

Instruction Manuals ............................................................................... 2

Contact Fluke Calibration ...................................................................... 2

Service Information ............................................................................... 2

Product Features ................................................................................... 3

Common Features ............................................................................. 3

8588A Reference Multimeter ............................................................. 4

8558A 8 1/2 Digit Multimeter ............................................................. 4

Installation ............................................................................................. 4

Unpack and Inspect the Product ....................................................... 4

Standard Equipment .......................................................................... 5

Placement and Rack Mounting.............................................................. 5

Cooling Considerations ..................................................................... 6

Environmental and Input Requirements ............................................ 6

Mains Voltage ........................................................................................ 7

Grounding the Product ...................................................................... 8

Line Power and Fuse ......................................................................... 9

Front and Rear Panel ............................................................................ 9

Front-Panel Features ......................................................................... 10

Rear-Panel Features ......................................................................... 14

Operation ............................................................................................... 16

Turn on the Product ........................................................................... 16

Power-Up State ................................................................................. 16

Warmup Requirements ...................................................................... 17

Functions ............................................................................................... 18

DC Voltage ........................................................................................ 18

Measure DC Voltage ......................................................................... 19

Simple Lead Connections .............................................................. 19

Common Mode Rejection - Use of External Guard Connection .... 20

AC Voltage ........................................................................................ 20

Measure AC Voltage ......................................................................... 24

Induced Inte

Common Mode Rejection .............................................................. 24

Lead Considerations ...................................................................... 24

rference

...................................................................... 24

i

8588A/8558A

Operators Manual

DC Current ........................................................................................ 25

AC Current ......................................................................................... 27

ACI Measure Setup ....................................................................... 28

Measure AC Current ...................................................................... 30

Resistance ......................................................................................... 31

Measure Resistance .......................................................................... 36

2-Wire Measurements ................................................................... 36

4-Wire Measurements ................................................................... 36

4-Wire High-Resistance Measurements ........................................ 37

4-Wire Resistance Zero ................................................................. 37

Ω Guard ......................................................................................... 38

Digitize ............................................................................................... 39

More ...................................................................................................... 48

Capacitance (8588A only) ................................................................. 48

RF Power (8588A only) ..................................................................... 50

RF Power Softkeys ........................................................................ 52

Connect a Power Sensor to the Product ....................................... 53

Connect a Power Sensor to a Unit Under Test ............................. 54

Set the Measurement Frequency .................................................. 54

Frequency Counter ............................................................................ 55

Measure Frequency ........................................................................... 58

DCI Ext Shunt (8588A Only) .............................................................. 59

ACI Ext Shunt (8588A Only) .............................................................. 62

Measure AC Current with ACI Ext Shunt ........................................... 68

PRT ................................................................................................... 69

Measure PRTs ................................................................................... 69

Thermocouple ....................................................................................... 71

Measure Thermocouples ................................................................... 71

Features ................................................................................................ 74

Input Terminal Selection .................................................................... 74

Use the Scan Operations .............................................................. 75

Scan Sequences ........................................................................... 76

4W Tru Ohm Scan Mode (Tru Ohms Ratio) ..................................

External Guard .............................................................................. 78

Output Signal ................................................................................. 79

TRIG OUT ..................................................................................... 80

Zero ................................................................................................... 83

Math ................................................................................................... 85

Analyze .............................................................................................. 88

Memory Setup ....................................................................................... 95

Instrument Setup ................................................................................... 97

Display Settings Submenu ................................................................ 98

Instrument Settings ............................................................................ 99

Remote Settings ................................................................................ 100

Calibration Adjust .............................................................................. 101

Diagnostics ........................................................................................ 103

Triggering Measurements ..................................................................... 104

Details of the Triggering Subsystem .............................................. 105

Trigger Indicator ................................................................................ 115

Examples of Using the Trigger Subsystem ................................... 116

Special Event Qualifiers ................................................................ 123

Guidelines to Avoid Measurement Errors .............................................. 125

Maintenance .......................................................................................... 127

Fuse Replacement ............................................................................ 127

Clean the Exterior .............................................................................. 128

Accessories ........................................................................................... 129

ii

76

Introduction

The Fluke Calibration 8558A 8 1/2 Digit Multimeter and 8588A Reference
Multimeter (the Product or Multimeter unless otherwise specified) are for
demanding and precise measurement applications. The Product functions in
both stand-alone and systems applications. 8 1/2 digit resolution provides high
performance and makes the Product well suited for application use in standards
labs, calibration labs, engineering labs, and systems use. The 8588A includes
more features and higher performance for the most demanding metrology
applications. The Products are accurate, stable, fast, and easy to use.

Safety Information

General Safety Information is located in the printed Safety Information document
that shipped with the Product. It can also be found online at www.Flukecal.com.
More specific safety information is listed where applicable.

A Warning identifies conditions and procedures that are dangerous to the user.
A Caution identifies conditions and procedures that can cause damage to the
Product or the equipment under test.

Specifications

Safety specifications are located in the printed Safety Information. Full
specifications are located online at www.flukecal.com in the 8558A/8588A
Specifications.

1

8588A/8558A

Operators Manual

Instruction Manuals

The Product user documentation is:

• 8588A/8558A Safety Information (printed, localized in 9 lang

• 8588A/8558A Operators Manual (provided onlin

available for purchase th
localized in

• 8588A/8558A Service Manual (provided online)

• 8588A/8558A Re

copy is available for purchase through the Fluke Calibration Service
Department)

To order, se
representative. See Contact Fluke Calibration.

This manual provides complete information to install and operate the Product
from the front panel.

9 languages)

mote Programmer’s Manual (provided online or a printe

e the Fluke Calibration Catalog or contact a Fluke Calibration sales

rough the Fluke Calibration Service Department,

Contact Fluke Calibration

To contact Fluke Calibration, call one of the following telephone numbers:

• Technical Support USA:

•

Calibration/Repair USA:

C

•

anada: 1-800-36-FLUKE (1-800-363-5853)

E

•

urope: [phone]

1-877-355-3225

1-877-355-3225

e or a printe

uages)

d copy is

d

• Japan: [phone]

•

ingapore: [phone]

S

•

hina: [phone]

C

Brazil: +55-

•

Anywhere in

•

To see product information and download the latest manual supplements, visit
Fluke Calibration’s website at www.flukecal.com.

To register your product, visit http://flukecal.com/register-product.

11-3759-7600

the world: [phone]

Service Information

Contact an authorized Fluke Calibration Service Center if the Product needs
calibration or repair during the warranty period. See Contact Fluke Calibration.
Please have Product information such as the purchase date and serial number
ready when scheduling a repair.

To reship the Product, use the original shipping container. If the original carton is
not available, then order a new container from Fluke Calibration. See Contact

Fluke Calibration.

2

Product Features

Common Features

The Products share a common chassis and display/hardware platform. They are
differentiated by additional precision components and firmware.

The Product shares these capabilities:

Reference Multimeter and 8 ½ Digit Multimeter

Product Features

• Inherent accuracy and stability without the need for periodic
automatic adjustments like the ACAL function

• Color display with user interface (UI) in English, Chinese, Fr
Japanese, K

• Visual Connection Management active terminal illumination

• Versatile resolution and reading rate settings:

o 8 1/2 to 4 1/2 digit resol

o

o 100 k readings/sec at 4 1/2 digits (18-bit) resolution in remo

• Digitizing function for specific digitizing applications with
provided by

Up to 5 Mega Samples/second sampling at 18 bits with up to 20 MHz

•

bandwidth

•

Programmable front/rear inputs, automatic ratio ohms, voltage,
using the fro

• Math, with null, normalize, scale, and average

•

Analyze, with graphing, trending and

•

Frequency measureme

orean, Russian and Spanish

ution

aperture time settings from 0 ns to 10 seconds (200 ns min resolution)

operation

an internal real-time cloc

nt/rear input

s.

nts to 100 MHz

k

statistics

ench, German,

timestamps and date

internal

te

and more

Capacitance measurements to calibrate multi-product calibrator

•

RF power meter readout for R&S NRP series pow

•

• GPIB SCPI, Ethernet, and USB remote interfaces

o

Standard IEEE-488 (GPIB) interface, complying with ANSI/I
Standards 488.1-1987 and 488.2-1987

Universal Serial Bus (USB) 2.0 high-speed interface device por

o

remote control with USB TMC

o

Integrated 10/100/1000BASE-T Ethernet port for network connect
remote control

• PRT and thermocouple readouts

•

Front and rear USB memory ports f

or data transfer

er sensors

s

EEE

t for

ion

3

8588A/8558A

Operators Manual

• Extensive Trigger modes

•

Software emulation of the Fluke 8508A and HP/Agilent/Keysight
remote interfaces

Digital rms ac technolog

•

• Extensive internal software-controlled self-testing and diagnostics of analog

and digital f

• Analog Zero to remove residual offsets, for example, from thermal EMFs

8588A Refe

8558A 8 1/2 Digit Multimeter

rence Multimeter

The 8588A has specifications suited for the most demanding calibration and
metrology applications.

The 8558A specifications are relaxed from those of the 8588A but its
specifications are comparable to other 8 1/2 digit multimeters.

unctions.

Installation

To prevent possible electrical shock, fire, or personal injury, do
not apply more than the rated voltage, between the terminals or
between each terminal and earth ground.

This section provides instructions to install the Product and connect it to line
power. Because this section explains fusing and operating environment
requirements, read this section before you operate the Product.

3458A

y

.

XWWarning

The Product should only be used to measure sources up to 1000 V dc or rms ac
that are protected from short circuit with current limiting to 200 mA or less.
Instructions to connect cables to other instruments and to a Device Under Test
(DUT) during operation are described in the Functions section.

Unpack and Inspect the Product

The Product ships in a container that prevents shipping damage. Inspect the
Product carefully for damage, and immediately report any damage to the shipper
Instructions for inspection and claims are included in the shipping container.

Unpack the Product and check for all the standard equipment listed in Standard
Equipment and check the shipping order for additional items ordered. Report any
shortage to the place of purchase or to the nearest Fluke Calibration Service
Center. See Contact Fluke Calibration if necessary. If performance tests are
required for your acceptance procedures, see the Product Service Manual for
instructions.

4

Reference Multimeter and 8 ½ Digit Multimeter

Standard Equipment

Check that all items listed in Table 1 are included:

Table 1. Standard Equipment

Item Fluke Calibration Part Number

8588A Reference Multimeter 4983182

8558A 8 ½ Digit Multimeter 4983194

Mains Power Cord See Mains Voltage

8558A/8588A Safety Information (printed) 4769456

Placement and Rack Mounting

8588A-LEAD KIT-OSP
General Purpose Probe Kit & Pouch

Calibration Certificate -

Placement and Rack Mounting

Put the Product on top of a workbench or mount the Product in a standard 48-cm
(19-inch) wide, 61-cm (24-inch) deep equipment rack. For bench-top use, the
Product has non-slipping, non-marring feet.

To mount the Product in an equipment rack, order the accessory Y8588 or
Y8588S for the sliding option.

XWWarning

To prevent possible electrical shock, fire, or personal injury, do
not restrict access to the Product mains power cord. The mains
power cord is the mains disconnecting device. If access to the
power cord is inhibited by rack mounting, a properly rated
accessible mains disconnecting switch must be provided within
reach as part of the installation.

4951331

5

8588A/8558A

Operators Manual

Cooling Considerations

WCaution

Damage caused by overheating can occur if the area around the
air intake or exhaust exit is restricted, the intake air is too
warm, or the air filter becomes clogged.

An important feature of the Product is its internal cooling system. Baffles direct
cool air from the fans throughout the chassis to dissipate heat during operation.
Maintain the coolest possible internal temperature to ensure the accuracy and
dependability of all internal parts of the Product.

The area around the air filter (power-switch side of the chassis) must be at least

7.5 cm (3 in) from nearby walls or rack enclosures. The exhaust perforations on

the rear of the Product must be clear of obstructions for 7.5 cm (3 in). Obstructed
airflow degrades Product performance.

To lengthen the life of the Product and ensure its performance:

• Keep the air filter at least 7.5 cm (3 in) from nearby walls or rack enclosu

Rear-Panel Features

See

.

• Make sure that the exhaust perforations on the rear of the Product are
unobstructed.

Do not direct exhaust from another instrument into the air inle

•

Air entering the Product must be room temperature.

•

Vacuum the air inlet and outlet areas every 30 days or more fr
Product is o

perated in a

dusty environment.

Environmental and Input Requirements

For full accu

racy, the Product must be used in an ambient temperature within

±5 °C of the temperature of the last calibration.

To operate the Product outside the specified temperature range, see the
temperature coefficients specifications. See Specifications.

XW Warning

To prevent possible electrical shock, fire, or personal injury,
limit voltage sources connected to the Product to ≤1050 V dc or
rms ac, and ≤200 mA. Do not connect voltages that have high­energy transients.

res.

t of the Product.

equently if the

6

Mains Voltage

To prevent possible electrical shock, fire, or personal injury:

• Do not put the Product where access to the mains power cord
is blocked.

Reference Multimeter and 8 ½ Digit Multimeter

Mains Voltage

XW Warning

• Use onl
the voltage and plug configuration in
for the Product.

• Make sure the ground conductor in the mains power cord is
connected to a protective earth ground. Disruption of the
protective earth could put voltage on the chassis that could
cause death.

• Replace the mains pow
if the insulation shows signs of wear.

• The Product enclosure must be grounded through the
grounding conductor of the power cord, or through the rear
panel ground binding post.

The Product comes with the appropriate line power plug for the country of
purchase. If a different type is necessary, see Table 2. They list and show the
mains line power plug types available from Fluke Calibration.

The Product automatically detects the main line voltage when powered up and
configures itself to work at that voltage level. Nominal mains voltages ranging
from 100 V rms to 120 V rms and from 220 V rms to 240 V rms ( each ±10 %) are
acceptable, with frequencies from 47 Hz to 63 Hz.

y the mains power cord a

er cord if t

nd connector approved for

your country and

he insulation is damaged or

rated

7

8588A/8558A

Operators Manual

Table 2. Available Mains Power Cord Types

Universal EuroNorth Ameri can/Japan United Kingdom

LC-1

Australia/ China

LC-6

LC-3

LC-4

South Africa Brazil

LC-7 LC-42

Type Fluke Calibration Option Number

North America 284174

Universal Euro 769422

United Kingdom 769455

Switzerland 769448

Australia 658641

South Africa 722771

Brazil 3841347

Swiss

LC-5

hwr039.emf

Grounding the Product

The Product enclosure must be grounded through the grounding conductor of the
power cord, or through the rear-panel ground binding post.

8

Line Power and Fuse

The line power receptacle and the fuse are located on the rear of the Product.
See Figure 1. Use only the fuse recommended by Fluke Calibration.

Reference Multimeter and 8 ½ Digit Multimeter

Front and Rear Panel

Figure 1. Line Power and Mains Fuse Location

Front and Rear Panel

This section provides descriptions of each panel feature. Read this information
before Product use. Front-panel operation instructions for the Product are in

Front-Panel Operation. Remote operations instructions are in Remote
Programmer’s Manual.

Features that are unique to either the 8588A or 8558A are noted as such.

iei003.emf

9

8588A/8558A

Operators Manual

Front-Panel Features

Front-panel features (all controls, display, indicators, and terminals) are shown
and described in Table 3.

Table 3. Front-Panel Features

2

3

3

1

Number Name Function





INPUT Terminals
A, HI, and LO

INPUT Terminals
VΩ, HI, and LO

24

4

23

5

22

A pair of five-way binding posts for current measurements. Signals
up to 30 A rms can be applied to these terminals on the 8588A and
up to 2 A on the 8558A.These terminals illuminate to show
connections.

A pair of five-way binding posts for voltage, ohms, capacitance, 2­wire PRT, and thermocouple measurements. On the 8588A, these
binding posts also connect to the output of external current shunts.
Frequency can be measured via these terminals. Signals up to
1050 V rms can be applied to these terminals. These terminals
illuminate to show connections.

67

18

20

21

19

17

9

16

10 811

14

15

12

13

Iei001.emf

10



SENSE Terminals
V, HI, and LO

D EXT PORT

E Color Display

F



(Navigation Keys)

A pair of five-way binding posts for 4-wire resistance measurements.
They are the sense terminals in 4-W Ω and 3- and 4-wire PRT.
These terminals illuminate to show connections.

A connector to use the Rodhe & Schwarz (R&S) NRP RF power
sensors. Note this terminal illuminates to show connections.

Color display shows the output and active conditions and messages.
The display provides controls not available with the keys alone by
use of softkeys F1 to F5. The localized Product interface is made up
of multiple menus, described throughout the manual. The display
outputs in numerical or graphing format.

Four-way navigation keys used to move from various menu choices
on the display when available. The active menu choice is highlighted.

Reference Multimeter and 8 ½ Digit Multimeter

Table 3. Front-Panel Features (cont.)

Number Name Function

Function Keys: These keys select one of the major functions for the Product. Push

any one of the function keys to take you immediately out of any
other display screen and into the top level of that function.

 Access the DCV (DC Voltage) function. See DC Voltage.

 Access the ACV (AC Voltage) function. See AC Voltage.

 Access the DCI (DC Current) function. See DC Current.

 Access the ACI (AC Current) function. See AC Current.

G

 Access the Ohms function. See Resistance.

 Access the Digitize function. See Digitize.

When pushed, makes other functions visible that can be selected in
the Product: Capacitance (8588A only), RF Power (8588A only),
Frequency Counter, DCI Ext Shunt (8588A only), ACI Ext Shunt



(8588A only), PRT readout, and Thermocouple readout. This key is
used in conjunction with
available functions. When one of the functions is selected under
More,

 illuminates. See More.

 (More) and cycles through the

Front and Rear Panel

H 

I 

Provides mathematical operations on measurements, for example,
averaging, multiplication by M, subtraction of C, and division by Z.
The Math annunciator on the display indicates that a Mathematical
operation is active. The Last Reading softkey () is useful to
quickly set C, Z, or m. See Math.

When selected, allows configuration of the front and rear terminals,
including front/rear ratio measurement, and shows their status.
Provides control of the External GUARD terminal and the rear TRIG
OUT BNC connector. Shows the softkeys that configure the front
and rear terminals, External Guard, and rear TRIG OUT BNC
connector.  (Terminals) gives selections for Front, Rear, and
shows three scan modes with different mathematical combinations
of the front and rear readings, and also an Isolated configuration.
 (Front Delay) sets the delay before the front terminals are
activated.  (Rear Delay) selects the delay before the rear
terminals are activated.  (External Guard) activates the
GUARD terminal (On or OFF). and  (Output Signal) is used
to set the behavior of the rear TRIG OUT BNC connector. See Input
Terminal Selection and TRIG OUT.

11

8588A/8558A

Operators Manual

Number Name Function

Table 3. Front-Panel Features (cont.)

J 

K Numeric keypad

L

M

USB Type A
Connectors

Mains Power
Switch

N 

O 

Starts a process that corrects for analog offset errors in an entire
function, or for a specific range. See Zero.

Numbered keys to enter various Product parameters and other data
such as the time and date.

 allows you to enter an exponent.

 clears the last entry and  clears the entire entry. Use

 to confirm all numerical entries.

These two USB ports function identically, allowing transfer of the
Product’s readings to a USB memory stick. Each port is capable of
providing 5 V at 0.5 A maximum, and supports an external keyboard
(but not a mouse). The Product does not uniquely identify the USB
ports. When you copy data, insert only one USB memory device.

In the 0 position, this switch isolates all mains power internally. Push
to the 1 position to turn on the Product.

The Analyze function provides different tools to analyze
measurements: Statistics, Trend, Histogram, and Limits. See
Analyze.

Push to change where readings are stored, change the result
format, and transfer readings between memory locations. See
Memory Setup.

P  Access the Instrument Setup menu. See Instrument Setup.

Q 

Access the menus to set the various triggering modes. See
Triggering Measurements.

Select the highlighted menu choice in conjunction with the

R 

navigation keys. A right pointing triangle > on the screen indicates
additional choices are available.

S  Moves the menu to the previous selection.

When the Trigger subsystem is continuously triggering (free run),
push

 once to put the Product into the non-continuous

T 

(idle) trigger state. Readings are not updated until a trigger event, for
example, when you push
the Product back into the continuous trigger (free-run) state. See
Triggering Measurements.

. Pushing  again puts

12

Reference Multimeter and 8 ½ Digit Multimeter

Table 3. Front-Panel Features (cont.)

Number Name Function

Triggers a measurement when the Product is in the non-continuous
trigger (idle) state. The idle state occurs when the Run/Stop key is

U 

pushed once.
when in Remote operation. See Triggering Measurements for details
about the Product Trigger subsystem.
when in digitize.

 is one of the few keys that is not disabled

Front and Rear Panel

 starts data capture

 

V

 


W GROUND

X GUARD

Five softkeys that select the menu item noted directly above each
respective key.

Five-way binding post connected to earth ground through the earth
ground connector on the mains plug. This terminal does not
illuminate.

This five-way binding post in the External Guard OFF state is
isolated from any internal connections, and the internal guard
shields are connected to the internal 0 V. In the External Guard ON
state, the internal guard shields are disconnected from the internal
0 V and connected to the GUARD terminal of the selected front or
rear input. In the Ohms or PRT functions, the External Guard ON
selection is modified to provide an ohms guard. To set the condition
of the External Guard (ON or OFF) push  to access 
(Ext. Guard). Guarding is explained throughout this manual. When
set to Ext. Guard ON, this terminal illuminates.

13

8588A/8558A

Operators Manual

Rear-Panel Features

Rear-panel features (including all terminals, sockets, and connectors) are shown
and described in Table 4.

Note

The rear-panel terminals do not have Visual Connection
Management active terminal illumination.

Table 4. Rear-Panel Features

123

18

45 7

3

69

14151617

13

Number Name Function



AC power input
connector

A grounded male three-prong connector for the mains power cord
that also houses the mains fuse.

 Serial number The Product Serial Number.

This co-axial BNC socket can be used to trigger a measurement

 TRIG IN

D TRIG OUT

when external triggers are enabled. The trigger in signal can be
either a TTL or Bipolar, with either a negative or positive slope. See
Triggering Measurements.

This co-axial BNC socket outputs a signal when a specified
measurement event occurs. The signal may be a TTL edge or a
square wave which is active during a particular process. This signal
is used to synchronize external equipment to the Product and is
comparable to the HP/Agilent/Keysight 3458A EXT OUT output. See
Input Terminals Selection.

8

11

12

10

iei002.emf

14

E Fan access holes

F

G

H

INPUT, A HI and
LO

INPUT, V HI and
LO

SENSE, V HI and
LO

Access holes for the internal fan. Air is expelled from the Product for
internal cooling through these holes. See Cooling Considerations.

A pair of five-way binding posts for current measurements. Signals
up to 2 A rms can be applied to these terminals.

A pair of five-way binding posts for voltage, ohms, capacitance, 2­wire PRT, and thermocouple measurements. On the 8588A, these
binding posts also connect to the output of external current shunts.
Frequency can be measured via these terminals. Signals up to
1050 V rms can be applied to these terminals.

A pair of five-way binding posts for 4-wire resistance measurements.
They are the sense terminals in 4-wire Ω and 3- and 4-wire PRT.

Reference Multimeter and 8 ½ Digit Multimeter

Table 4. Rear-Panel Features (cont.)

Number Name Function

Holds the fuse that is in series with the rear Input A Hi input. F1.6AH

I Fuse holder

250 V fuse protects the current-measuring circuity when using the
rear terminals for signal input.

Front and Rear Panel

J GROUND

K GUARD

L

FREQ COUNTER
IN

M FREQ REF IN

N

O

USB Type A
connector

USB Type B
connector

Five-way binding post connected to earth ground through the earth
ground connector on the mains plug.

This five-way binding post in the External Guard OFF state is isolated
from any internal connections, and the internal guard shields are
connected to the internal 0 V. In the External Guard ON state, the
internal guard shields are disconnected from the internal 0 V and
connected to the GUARD terminal of the selected front or rear input.
In the Ohms or PRT functions, the Ext. Guard ON selection is
modified to provide an Ohms Guard. Guarding is explained
throughout this manual.

This is a 50 Ω impedance input to the frequency counter function.
See Frequency Counter. Measure a frequency input from the Volt
INPUT HI-LO terminals, or through this BNC connector.

A reference 10 MHz signal can be applied to this BNC connector to
provide the Product with an external frequency reference. Intended
to be used in a system where several devices are phase locked to a
common reference and can reduce trigger latency.

USB port to allow transfer of the Product’s readings to a USB
memory stick. This port is capable of providing 5 V at 0.5 A
maximum, and supports an external keyboard (but not a mouse).
See Memory Setup.

USB port for port for remote control of the Product. See USB
Interface. See the Remote Programmer’s Manual.

P LAN connector

Q

IEEE-488
connector

R AC mains fuse

10/100/1000 Base/T Ethernet connector for remote control of the
Product. Remote Interface Setup in the Remote Programmer’s
Manual describes proper cabling, how to set up the interface, and
how to transmit data from the Product. Remote Interface Setup also
describes how to use the Ethernet interface for remote control. See
the Remote Programmer’s Manual.

A standard GPIB interface connector to operate the Product in
remote control as a Talker or Listener on the IEEE-488 Bus. See

Remote Interface Setup for bus connection. See the Remote
Programmer’s Manual for remote programming instructions.

The T1.25AH 250V mains fuses are accessible after removing the
mains power cord. See Maintenance.

15

8588A/8558A

Operators Manual

Operation

Turn on the Product

This section explains Product operation. See Front and Rear Panel for key and
feature locations. Remote interface setups are explained in the Remote
Programmer’s Manual. The first part of this section is general and applies to all
modes of operation.

Operating instructions are presented separately for each function.

XWWarning

To avoid electric shock, make sure that the Product is
grounded before use.

Before you turn on the Product, see Grounding the Product.

To turn on the Product, push in the power switch on the front panel. When the
Product is turned on, it takes approximately 20 seconds to complete its power-up
process. During the power-up process, the Product goes through a series of self­tests. If a self-test fails, a prompt on the display identifies the failed test and
prevents further operation. If the test fails, contact Fluke Calibration.

Power-Up State

After passing the power-up self-tests, the Product goes into the power-up state.
When you turn on the power (with no input attached), the Product starts in DCV,
1000 V (1 kV) range

.

16

Reference Multimeter and 8 ½ Digit Multimeter

Table 5 summarizes the non-volatile setup parameters and their factory defaults.

Table 5. Non-volatile Setup Parameter Factory Defaults

Operation

Setup Parameter

Remote Port GPIB

IEEE-488 Bus (GPIB) Address 18

Real Time Clock Date Not changed

Real Time Clock Time Not changed

Date Format dd/mm/yyyy

Time Format 12 hour

Language English

Display Brightness 50 %

Backlight dimmer 30 minutes

Line Frequency 50 Hz

Trigger Out Signal acquired

GPIB EOL setting EOI

Ethernet Settings Several of them including LXI settings

USB Remote interface Computer

(Value after Non-Volatile Memory Format)

Factory Default

USB EOL CRLF

Emulation mode None

Active calibration stores Certified

Math OFF

Math constants Not changed

Warmup Requirements

You can use the Product as soon as it has completed its self-tests, but a 3-hour
warm-up period is required to ensure that the Product meets or exceeds its
specifications. See Specifications.

If you turn off the Product after it has warmed up, allow it to warm up again for at
least twice the length of time it was turned off (up to a maximum of 3 hours). For
example, if the Product is turned off for 10 minutes, allow it to warm up again for
at least 20 minutes.

https://www.elso.sk/product.php?id_product=1020

17

8588A/8558A

Operators Manual

Functions

DC Voltage

DCV Menu

The subsequent sections explain the different functions of the Product.

The DC Voltage function provides 2-wire measurements using the V INPUT HI
and LO Input terminals. Push  to use the DC Voltage (DCV) function.

The ranges available are:

100 mV to 1000 V, where the 100 mV to 100 V ranges provide 202 % overrange,
for example, the 1 V range displays up to 2.02 V. The 1000 V range can measure
up to 1050 V.

This section explains the available DCV menu.

 (Range): Each of the dc V ranges can be manually selected or select
Auto to put the Product into Autorange. Make the range selection with the
softkeys or use the navigational keys to highlight the selection and push .
Push  to return to the start page of the menu.

 (Resolution): DCV has resolution from 4 1/2 digits to 8 1/2 digits. Select
resolution with the softkeys or use the navigational keys to highlight the selection
and push . Push  to return to the start page of the menu. The A to D
aperture times associated with each resolution setting are shown in the Product
specifications. See Specifications.

 (Z in): DCV has selectable input impedances. Auto provides 1 TΩ for the
100mV, 1V, and 10V ranges, and 10 MΩ for the 100V and 1kV ranges. 10 MΩ
provides 10 MΩ input impedance for all five ranges. Use 1 MΩ for ac/dc transfers
where the ac input impedance is set to 1 MΩ. Make the input impedance
selection with the softkeys or use the navigational keys to highlight the selection
and push . Push  to return to the start page of the menu.

 (Measure Setup): Sets the integration time of the A to D converter. The
choices are:

uto

• A

A

•

uto Fast

M

•

anual

18

Reference Multimeter and 8 ½ Digit Multimeter

Functions

When you select Manual, use the softkeys and the numerical keypad to edit the
integration time by PLC and Time. The smallest time aperture is 0 seconds with
200 ns increments and has an upper time limit of 10 seconds.

PLC refers to Power Line Cycles. A PLC at a 50 Hz line is 20 ms; a PLC at a
60 Hz line is 16.67 ms. The smallest aperture that can be set by PLC is 0.01. The
upper limit is the PLC equivalent of 10 seconds so is determined by the line
frequency setting in the Instrument Setup menu. For a 50 Hz line setting, the
maximum is 500 PLC, for a 60 Hz setting it is 600 PLC.

When the aperture is set by time, the display shows the nearest equivalent PLC
to 0.01 PLC precision. When the aperture is set by PLC, the display shows the
aperture in seconds with 200 ns resolution.

Use the navigation keys and  to choose the aperture setting method. The
aperture settings for Auto and Auto Fast for different resolution settings are
shown in Table 8.

Measure DC Voltage

The sections below explain how to accurately measure dc voltage.

Simple Lead Connections

For the majority of applications, the simple lead connection without external
guard is adequate as in Figure 2. Use and then  (Ext. Guard OFF).
See Input Terminal Selection (INPUTS). The disadvantage of this arrangement is
that the lead connection can form a loop. If a stray alternating magnetic field
(from the line transformer of a neighboring instrument, for example) passes
through the loop, it behaves as a single-turn secondary winding inducing
unwanted ac voltages into the measuring circuit. Use a twisted-pair to reduce the
loop area and adjacent twists will cancel any induced voltages. If you encounter
problems with stray pick-up, Fluke Calibration recommends that you use a
shielded twisted-pair cable with the screen connected to the INPUT LO terminal
at the source as shown in Figure 3.

Figure 2. Simple Lead Connections

Figure 3. Twisted-Pair Cable Connections

adj059f.emf

adj060f.emf

19

8588A/8558A

Operators Manual

Common Mode Rejection - Use of External Guard Connection

When the source presents an unbalanced impedance to the measuring
terminals, and common mode voltages are present, use the GUARD terminal
with External Guard selected. Use  and then  (Ext. Guard) to
activate the GUARD terminal. See Input Terminal Selection (INPUTS).
Regardless of how the INPUT HI and LO terminals are connected, the GUARD
terminal should be referred to the source of common mode voltage, see Figure 4.
This minimizes errors caused by common mode currents in the measuring circuit
by providing a separate common mode current path.

R1, C1 = Input impedance

Icm

Loop

R2, C2 = Input-to-Guard

R3, C3 = Guard-to-Case

Vcm1, = Common Mode
Vcm2 Voltages
I cm = Common Mode

leakage impedance

leakage impedance

Current

AC Voltage

The AC Voltage function provides 2-wire measurements using the V INPUT HI
and LO terminals. Push  to use the AC Voltage (ACV) function. The
Product makes true-rms ac voltage or ac+dc voltage measurements using a
proprietary sampling method with up to 10 MHz bandwidth. These ranges are
available:

10 mV to 1000 V, where the 10 mV to 100 V ranges provide 121.2 % overrange.
Full scale is 121.2 % of range for these ranges. For example, the 1 V range can
show up to 1.212 V. The 1000 V range can measure up to 1050 V rms.

Input impedance is selectable from 10 MΩ, 1 MΩ, or Auto when dc coupled. Auto
selects the highest impedance available.

Figure 4. External Guard Connections

adj061f.emf

20

Reference Multimeter and 8 ½ Digit Multimeter

Functions

AC Voltage Menu

This section explains the AC Voltage (ACV) menu. See the screen below.

iei005.png

 (Range): Select each of the ac V ranges manually or select Auto to put
the Product into Autorange. Make the range selection with the softkeys or use
the navigational keys to highlight the selection and push .

 (Resolution): ACV has resolution from 4 1/2 digits to 7 1/2 digits. The
default is 6 1/2 digits. To choose the resolution, use the softkeys or the
navigational keys. Push the navigational keys to highlight the selection and then
push .

 (Band): ACV has selectable-bandwidth settings.

The Product has these available settings:

• Wideband (default)

• Extended High Frequency

Most applications should use Wideband which measures signals up to 2 MHz
and where the wave shape of the signal is not necessarily known. It is the default
setting and is a general-purpose ac voltage measurement function.

Extended High Frequency extends the ACV frequency range to 10 MHz. This
mode is about three times slower and less accurate than Wideband.

21

8588A/8558A

Operators Manual

 (RMS Filter): Push to select various filters for the rms converter, allowing
measurements down to the chosen filter frequency without degradation of
accuracy and excessive reading variation. One of the filters is always in circuit.
The 40 Hz filter is the default selection at power on. The filter choices available
are 0.1 Hz, 1 Hz, 10 Hz, 40 Hz, 100 Hz and 1 kHz. See Specifications. Use the
softkeys or the navigational keys to highlight the selection and then push .
Push  to return the Product to the previous menu.

 (Measure Setup): Has parameters that can be set up for ac voltage
measurements. Use the softkeys or the navigational keys to highlight the
selection and then push . Push  to return the Product to the
previous menu. See the screen below:

iei022.png

The parameters under this menu are:

• Signal path coupling, impedance: (note that this selection determines what
is available in Frequency path coupling) these different combinations of signal
path coupling and impedance are available:

o  (AC, 1 MΩ)

o  (DC, 1 MΩ)

o  (AC, 10 MΩ)

o  (DC, 10MΩ)

o  (DC, Auto)

Most applications should use the 1 MΩ input impedance (default) as the
10 MΩ input has relaxed specifications. DC Auto selects the highest
impedance available for any given range.

22

Reference Multimeter and 8 ½ Digit Multimeter

Functions

• Secondary reading: The ACV function can show a secondary reading.

The choices are:

o  (OFF) (none)

o  (Frequency)

o  (Period)

o  (Pk to Pk)

o  (More)

o  (Pk to Pk) (Repeated for ease of use)

o  (Crest Factor)

o  (Positive Peak)

o  (Negative Peak)

When you select Pk to Pk, the last submenu in ACV Measure Setup, Peak to
peak method becomes active (see Peak to peak method below).

• Frequency path coupling: Frequency path coupling can be either ac or dc if
the Signal path coupling, impedance (above) is set to any of the dc
settings. Otherwise, only ac is available and this submenu is inactive.

• Frequency path bandwidth limit: (OFF or ON). Reduces noise in the
frequency counter signal path. If there is excessive noise, turn the bandwidth
limit ON for signals <2 MHz.

• Counter Gate can be set to:

o  (Auto)

o  (1 ms)

o  (

o  (100

o  (1 s

10 ms)

ms)

)

The counter gate auto times are related to the RMS filter and shown in Table 6.

Table 6. Counter Gate Auto Times

RMS Filter Gate Times

0.1 Hz 1 s

1 Hz 1 s

10 Hz 100 ms

40 Hz 100 ms

100 Hz 10 ms

1 kHz 10 ms

23

8588A/8558A

Operators Manual

Measure AC Voltage

In auto, the gate time is the longest of the cardinal times that will not reduce the
reading rate. If the gate time is set manually, the reading rate is the longest of
RMS filter and gate times.

ACV measurements wait for both the RMS filter settling and the counter gate,
whichever is the longer. If you select long counter gate times, this may slow the
reading rate. The auto times are chosen to not slow the read rate.

• Peak to peak method: This submenu is active when the Secondary Reading
is set to Pk to Pk. Measured shows the peak to peak as measured in ACV
assuming no particular signal wave form. Sine, Square, Triangle, and
Truncated Sine specify the signal wave form that is measured, and calculates
the peak to peak based on the rms value. For example, if set to Sine, the
peak to peak displayed is 2 x (square root of 2) x rms. Square is 2 x rms,
Triangle is 2 x (square root of 3) x rms, and Truncated Sine is 4.618803 x
rms. Use the Square, Triangle and Truncated Sine selections to measure the
peak-to-peak output of multi-product calibrators like the Fluke 5522A which
have these non-sine wave outputs.

The sections below explain how to accurately measure ac voltage.

Induced Interference

If interference signals are present or lead interference (noise) takes place during
ac measurements, any induced interfering signals combine with the measured
signal to result in measurement errors. In some circumstances, it may be
possible to filter out the unwanted external signals, but it is generally more
effective to reduce the interference before it is induced. Accomplish this by
operating in a quiet environment, for example, using a screened cage if possible
and using twisted or shielded measurement leads as discussed below.

Common Mode Rejection

The principles of external guarding, outlined in the description of dc voltage
measurement, apply generally to ac voltage measurement. For ac, you gain
further advantage by using the external guard as a shield for the input leads.

Lead Considerations

In all cases, improve ac voltage measurement accuracy by shortening the leads
to the minimum-practical length. Doing this reduces lead capacitance, lead
inductance, and loop area.

Fluke Calibration recommends shielded twisted pair leads for low-frequency
measurements and coaxial leads for low and high frequency measurements.
Take care to avoid measurement errors from the interaction of lead capacitance
and inductance with any source output impedance. For additional information
and guidance, see the Fluke publication Calibration: Philosophy in Practice
(ISBN 0-9638650-0-5). See the ACV Reading Rate for RMS Filter Settings
Specification in the specifications. See Specifications.

24

Reference Multimeter and 8 ½ Digit Multimeter

Functions

DC Current

The DC Current function provides current measurement using the INPUT A and
LO terminals. Push  to put the Product into the DC Current (DCI) function.

• Full scale is 202 % of range, except the 30 A range. For example the 1 A
range can display up to 2.02 A.

• The front terminals are electronically-protected and measure up to 30 A
(8588A) or 2 A (8558A).

• The rear terminals are protected with a user-replaceable fuse on the rear
panel and measure up to 2 A.

DCI Menu

This section explains the DCI menu.

 (Range): Each of the ranges can be selected or the Product can be put
into autorange by selecting Auto. The ranges available are 10 µA to 30 A for the
8588A and up to 1 A (202 % overrange) for the 8558A. Resolutions vary from
7 1/2 digits to 4 1/2 digits. 10 µA to 10 A ranges provide 202 % overrange.

The 30 A range can measure up to 30.2 A.

Note

10 A and 30 A ranges are not available when using the rear inputs.

Make the range selection with the softkeys or use the navigational keys to
highlight the selection and push .

 (Resolution): DCI has resolution from 4 1/2 digits to 7 1/2 digits. The
default is 7 1/2 digits. Make the resolution selection with the softkeys or use the
navigational keys to highlight the selection and push .

 (Measure Setup): Push to select the Measure Setup which has selections
for the reading rate. The choices are:

• Auto

• Auto Fast

• Manual

When Manual is selected, PLC and Time can be edited with the softkeys and the
numerical keypad. Push  (Edit PLC) or OFF  (Edit Time).

25

8588A/8558A

Operators Manual

Measure DC Current

The Product measures current with the INPUT A and INPUT LO terminals. The
current should flow from the source’s high terminal into the multimeter A terminal
and back to the source’s low terminal out of the multimeter LO terminal.

Similar connection considerations are required for dc current measurement as for
dc voltage measurement. Use shielded twisted-pair cable to reduce induced
interference signals, and connect GUARD to the source of common-mode
voltage to provide a separate common-mode current path.

XW Warning

HIGH CURRENT FLOW

To prevent possible electrical shock, fire, or personal injury,

• Do not exceed the Measurement Category (CAT) rating of
the lowest rated individual component of a Product, probe,
or accessory.

• Only use probes, test leads, and accessories that have the
same measurement category, voltage, and amperage ratings
as the Product. High current can cause excessive heating of
underrated conductors and may cause a fire.

Note

The current path between the Product terminals is not made when
the current functions are not in use or when front or rear terminals
are deselected.

The rear input terminals may be used to measure currents up to 2 A
only. The rear input A terminal does not share the front panel
automatic protection circuitry, and is instead protected by a fuse
mounted on the rear panel.

Maximum input current capability and protection: The front input
terminals may be used to measure currents up to 30.2 A with
protection for all ranges up to 30.2 A. The front input A terminal
protection for current ranges 1 A and lower has an overload
protection feature if the input significantly exceeds full range. This
protection is automatic and self-resetting, and does not interrupt
current flow. It remains engaged for 1 second after the overload is
removed to minimize circuit interaction and relay reactivation.

WCaution

Damage will occur if >30.2 A is applied to the front current
terminals and the current source maximum compliance is >5 V.

26

Reference Multimeter and 8 ½ Digit Multimeter

Functions

AC Current

The AC Current function provides measurements that use the INPUT A and LO
Input terminals. Push  to put the Product into the AC Current (ACI)
function. The AC Current function features 8 ranges (10 μA to 30 A) for the
8588A and 6 ranges (10 μA to 1 A) for the 8558A. The 10 µA, 100 µA, 1 mA,
10 mA, 100 mA and 10 A, ranges provide 202 % overrange. For example, the
10 A range displays up to 20.2 A. The 30 A range measures up to 30.2 A.

Note

The 10 A and 30 A ranges are not available on the rear inputs.

Resolution can be set from 7 1/2 digits to 4 1/2 digits. The default is 6 1/2 digits
of resolution.

The Product uses a proprietary sampling method to make true-rms ac current
measurements.

ACI Menu

The available ACI menu softkeys are explained below:

 (Range): Each of the ranges can be selected or the Product can be put
into autorange by selecting Auto. Make the range selection with the softkeys or
use the navigational keys to highlight the selection and push .

 (Resolution): ACI has resolution from 4 1/2 digits to 7 1/2 digits. The
default is 6 1/2 digits. Make the resolution selection with the softkeys or use the
navigational keys to highlight the selection and push .

Note

ACI, unlike ACV, has no Band selection. The Product uses the
wideband setting for all ACI measurements, measuring signals up to
100 kHz.

 (RMS Filter): Provides selection of various filters for the rms converter.
These filters allow measurements to be made down to the chosen filter frequency
without degradation of accuracy and excessive reading variation. One of these
filters is always in the circuit. The 40 Hz filter is the default selection at power on.
The filter choices available are 0.1 Hz, 1 Hz, 10 Hz, 40 Hz, 100 Hz and 1 kHz.
Make the selection with the softkeys or use the navigational keys to highlight the
selection and push . The filter setting determines the reading rate in ACI.
See the specifications for the AC filter settings and reading rates. See
Specifications.

27

8588A/8558A

Operators Manual

ACI Measure Setup

 (Measure Setup): The Measure Setup softkey in ACI menu has
parameters that can be set up to make ac current measurements. Parameter
choices are:

• Signal path coupling

• Secondary Reading

• Frequency path coupling

• Frequency path bandwidth limit

• Period/Frequency resolution

• Peak to peak method

Make the selection with the softkeys or use the navigational keys to highlight the
selection and push . See ACI Measure Setup.

There are parameters in the ACI Measure Setup menu that can be changed.

• Signal path coupling: Choose  (AC) or  (DC).

Note

This coupling affects the signal at the output of the Products internal
current shunt, as the input signal is always directly connected to the
Product internal current shunt.

• Secondary Reading: In the ACI function, a secondary reading can be
shown. The menu choices are:

o  (OFF) (none)

o  (Frequency)

o  (Period)

o  (Pk to Pk)

o  (More) additional Secondary Reading parameters

  (Pk to Pk) (repeated here for ease of use)

  (Crest Factor)

  (Positive Peak)

  (

  (Mor

Negative Peak)

e) Push to return to the

primary menu parameters.

When Pk to Pk is selected, the last submenu in ACV Measure Setup, Peak
to peak method becomes active. (see below).

28

Reference Multimeter and 8 ½ Digit Multimeter

Functions

• Frequency path coupling: The frequency path coupling can be AC or DC if
the Signal path coupling, impedance (above) is set to any of the dc settings.
Otherwise, only ac is available and this submenu is not operational.

• Frequency path bandwidth limit: Choose  (OFF) or  (ON).
Reduces noise in the frequency counter signal path. If there is excessive
noise observed, turn the bandwidth limit ON for signals <70 kHz.

• Counter Gate: Set to:

• 

(Auto)

•  (1ms)

•  (10ms)

•  (100ms)

•  (1s)

The counter gate auto times are related to the RMS filter and shown in Table 7.

Table 7. Counter Gate Auto Times

RMS Filter Gate Times

0.1 Hz 1 s

1 Hz 1 s

10 Hz 100 ms

40 Hz 100 ms

100 Hz 10 ms

1 kHz 10 ms

In auto, the gate time is the longest of the cardinal times that will not reduce the
reading rate. If the gate time is set manually, the reading rate is the longest of
RMS filter and gate times.

ACI measurements wait for both the RMS filter settling and the counter gate,
whichever is the longer. If you select long counter gate times, this may slow the
reading rate. The auto times are chosen to not slow the read rate.

29

8588A/8558A

Operators Manual

• Peak to peak method: This submenu is made active when the Secondary
Reading is set to Pk to Pk.

o Measured () shows the peak to peak as measured in ACI

assuming no particular signal wave form.

o  (Sine)

o  (Square)

o  (Triangle)

o  (Truncated Sine)

 through  specify the signal wave form type that is measured, and
calculates the peak to peak based on the rms value.

For example, if set to:

 Sine, the peak to peak shown is 2 x (square root of 2) x rms

 Square is 2 x rms

 Triangle is 2 x (square root of 3) x rms

 Truncated Sine is 4.618803 x rms

The Square, Triangle and Truncated Sine selections are useful to measure the
peak-to-peak output of multi-product calibrators like the Fluke 5522A which have
these non-sine wave outputs.

Measure AC Current

The Product measures ac current with its INPUT A and INPUT

Similar connection considerations are required for ac current measurement as for
ac voltage measurement. Use shielded twisted pair cable to reduce induced
interference signals, and connect GUARD to the source of common mode
voltage with the screen, to provide a separate common mode current path. The
Product minimizes the burden (compliance) voltage generated for current
measurements and thus, improves measurement accuracy. Fluke Calibration
recommends that leads of the minimum-practical length be used to reduce lead
capacitance, lead inductance, and loop area.

When you make ac current measurements pay close attention to the lead
impedance, especially lead capacitance at high frequencies on the lower current
ranges. (See Measure AC Voltage)

To prevent possible electrical shock, fire, or personal injury, do
not exceed the Measurement Category (CAT) rating of the
lowest rated individual component of a Product, probe, or
accessory.

LO terminals.

XW Warning

HIGH CURRENT FLOW

30

Only use probes, test leads, and accessories that have the
same measurement category, voltage, and amperage ratings as
the Product.

Reference Multimeter and 8 ½ Digit Multimeter

Functions

Note

The current path between the Product terminals is not made when
the current functions are not in use or when front or rear terminals
are deselected.

The rear input terminals may be used to measure currents up to 2 A
only. The rear input A terminal does not share the front panel
automatic protection circuitry, and is instead protected by a fuse
mounted on the rear panel.

Maximum input current capability and protection: The front input
terminals may be used to measure currents up to 30.2 A with
protection for all ranges up to 30.2 A. The front input A terminal
protection for current ranges 1 A and lower has an overload
protection feature if the input significantly exceeds full range. This
protection is automatic and self-resetting, and does not interrupt
current flow. It remains engaged for 1 second after the overload is
removed to minimize circuit interaction and relay reactivation.

WCaution

Damage will occur if >30.2 A is applied to the front current
terminals and the current source maximum compliance is >5 V.

Resistance

Push  to use the Resistance Measurement (Ohms) function. The
Resistance Measurement function provides 2-wire measurements using the
INPUT HI and LO terminals, or 4-wire measurements when you use the HI and
LO SENSE terminals. The available ranges are 1 Ω to 10 GΩ, all with 202 %
overrange.

Ohms Menu

This section explains the Ohms menu.

 (Range): Range selection is made with this softkey and the navigational
keys. The ranges available change with ohms mode. In 2W and 4W Normal, and
4W Tru you choose Auto or from 1 Ω to 1 GΩ. In 2W and 4W HV mode, the
ranges available are 10 MΩ to 10 GΩ. Highlight the choice and then push

.

 (Resolution): Resistance has resolution from 4 1/2 digits to 8 1/2 digits.

The default is 7 1/2 digits. Choose the resolution with the softkeys or use the
navigational keys and push .

 (Mode): There are five resistance modes, 2W Normal, 4W Normal, 4W
Tru, 2W HV, and 4W Hv. See Resistance Modes.

 (Lol): This softkey is context sensitive, available for all modes except 2W
HV and 4W HV. For many of the ohms ranges, LoI ON changes the
measurement current which reduces the self-heating in the DUT or to avoid
conduction of any parallel semi-conductor junction. The same 10 ranges, 1 Ohm
to 1 G Ohm, are available with LoI ON or OFF. The range and current used for
any range are shown in the information portion of the display. See Table 9 for the
current stimulus used based on the Product ohms range.

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8588A/8558A

Operators Manual

Note

With LoI ON, the behavior of auto ranging is modified such that the

Ω

Product will not auto range up from the 10 k
from the 100 M

Ω

to 1 GΩ range. This algorithm was chosen since

to 100 kΩ range, nor

the voltage compliance changes from 0.2 V to 2 V and 2 V to 20 V
on the respective range transitions. The higher compliance may
adversely affect a semi-conductor junction. The auto range down
behavior is the same as LoI OFF.

 (Measure Setup): Sets the aperture of the A to D converter and the Ohms
Filter. Aperture choices are:

• Auto, Auto Fast

• Manual

When you select Manual, use the softkeys and the numerical keypad to edit the
aperture by PLC and Time. The smallest time aperture is 0 ns with 200 ns
increments and has an upper time limit of 10 seconds.

PLC refers to Power Line Cycles. A PLC at a 50 Hz line is 20 ms; a PLC at a
60 Hz line is 16.67 ms. The smallest aperture that can be set by PLC is 0.01. The
upper limit is the PLC equivalent of 10 seconds so is determined by the line
frequency setting (Instrument Setup). For a 50 Hz line setting, the maximum is
500 PLC, for a 60 Hz setting it is 600 PLC.

When the aperture is set by time, the display shows the nearest equivalent PLC
to 0.01 PLC precision. When the aperture is set by PLC, the display shows the
aperture in seconds with 200 ns resolution.

Use the navigation keys and  to choose the aperture setting method. The
aperture settings for Auto and Auto Fast for different resolution settings are
shown in Table 8.

Table 8. Aperture Settings

Resolution Auto Fast Auto

4 200 μs 2 ms

5 2 ms 1 PLC

6 1 PLC 0.1 s

7 0.2 s 1 s

8 2 s 10 s

The Ohms Filter is selected using the navigation keys and either F1 OFF or F2
ON. The Ohms filter is a single-pole analog filter for increased noise rejection.
The Filter annunciator in the information portion of the display indicates that the
filter is active. The ohms filter is not available in 4W Tru Ohms.

32

Reference Multimeter and 8 ½ Digit Multimeter

Functions

Note

The pole or time constant of the filter is formed by a 22 nF capacitor
across the resistance under test.

Note

The selected range and resolution are remembered across Normal,
Tru ohm, and HV modes. For example, if Auto and 8 Digits are set in
2W Normal, they are also set in 4W Normal. If 4W Tru ohm is set to
the 100 ohm range and 7 digits, this does not affect the 2W and 4W
Normal Range and Resolution settings. The same is true for 2W and
4W HV ohms modes, they have their own range and resolution
settings.

LoI can be set individually for 2W Normal, 4W Normal, and 4W Tru,
and is remembered across these modes.

The Aperture setting (under Measure Setup) holds true for all of the
ohms modes, so once set, it used for all of the modes.

The Filter ON setting applies to the specific mode it was turned ON
in. and can be individually set for any of the modes, except 4W Tru
which does not allow Filter ON.

Resistance Modes

In the Ohms menu, when  (Mode) is pushed, different modes for making
resistance measurements are presented:

• 2W Normal Ω : This is the default setting and uses stimulus currents that
balance minimal self-heating of the resistance being measured with low
reading noise. 10 ranges are available, 1 Ω to 1 GΩ. 2-wire measurements
are made in this mode. The range and current used for that range are shown
in the information portion of the display. See Table 9 for the current stimulus
used based on the Product ohms range.

• 4W Normal: This setting is the same as 2W Normal except the
measurements are made using the 4-Wire measurement method.

• 4W Tru Ω : Using the 4-Wire measurement method, this mode uses a Tru
Ohms configuration and makes two measurements per reading, where the
second measurement is made with the current reversed relative to the first
measurement. The two measurements are combined to eliminate the effects
of any external EMFs that may be present. This mode provides 4-wire
measurements of resistance, in decade ranges from 1 Ω to 10 kΩ, and Auto
Ranging. The stimulus current is fed through the test resistance from the
Product’s INPUT HI and LO terminals, and the resulting potential difference is
sensed by the SENSE HI and LO terminals. The range and current used for
that range are shown in the information portion of the display. See Table 9 for
the current stimulus used based on the Product ohms range.

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Operators Manual

• 2W HV Ω: This mode provides 2-wire measurements of resistance, in decade
ranges from 10 MΩ to 10 GΩ. The measurement is performed at High
Voltage using a current source with high compliance. The resulting increase
in current through the unknown resistor reduces uncertainties due to leakage
and bias current. HV Ω may also be used in conjunction with the Normal Ω
mode to determine voltage coefficient in the unknown resistor. The
MAXIMUM voltage that could appear across the measured resistor is 240 V.
No autoranging is provided in this function. The range and current used for
each range are shown in the information portion of the display. See Table 9
for the current stimulus used based on the ohm range of the Product.

• 4W HV Ω: This mode is the same as 2W HV ohms except it uses the 4-Wire
measurement method.

XWWarning

To prevent possible electrical shock, fire, or personal injury:

• Do not connect external capacitance >50 nF to the Product
terminals. The maximum voltage across the measured
resistor or open Product terminals while using the HV Ω
function is 240 V. The maximum current that the Product will
source while using HVΩ is 10 μA (LO to HI), or 2.0 mA
(GUARD to HI if Ext. Guard is selected). These
characteristics are not considered “Hazardous Live” within
the Safety standards applied to this product. However,
capacitors (>50 nF) external to the Product could
accumulate LETHAL charge while making a HVΩ
measurement. Do not touch the Product terminals or
circuitry under test unless you are sure it is safe to do so.

• Do not exceed the Measurement Category (CAT) rating of
the lowest rated individual component of a Product, probe,
or accessory.

• Only use probes, test leads, and accessories that have the
same measurement category, voltage, and amperage ratings
as the Product.

34

Reference Multimeter and 8 ½ Digit Multimeter

Functions

Current stimulus values are shown in Table 9 for each of the five resistance
modes.

Table 9. Ohms Stimulus Levels for Each Mode

2W and 4W

Range

1 Ω 100 mA 100 mA ±100 mA ±100 mA NA

10 Ω 10 mA 10 mA ±10 mA ±10 mA NA

100 Ω 10 mA 1 mA ±10 mA ±1 mA NA

1 kΩ 1 mA 100 µA ±1 mA ±100 µA NA

10 kΩ 100 µA 10 µA ±100 µA ±10 µA NA

100 kΩ 100 µA 10 µA NA NA NA

1M Ω 10 µA 1 µA NA NA NA

10 MΩ 1 µA 100 nA NA NA 10 µA

100 MΩ 100 nA 10 nA NA NA 1 µA

1 GΩ 10 nA 10 nA NA NA 100 nA

10 GΩ NA NA NA NA 10 nA

2W and 4W

Normal

Normal

with LoI

ON

4W Tru Ω

Tru Ω LoI

4W Tru

ohm with

LoI ON

2W and 4W

HV Ω

35

8588A/8558A

Operators Manual

Measure Resistance

2-Wire Measurements

For many applications the simple 2-wire arrangement will be adequate. See
Figure 5. However, the value shown includes the resistance of the connecting
leads.

Use a shielded twisted-pair cable, preferably of PTFE insulation, to reduce
induced voltages, induced charge and shunt leakage resistance, particularly
where Rx is high.

2-wire resistance measurement is not available in a Tru Ohms configuration and
is not well suited to use in the 1 Ω range even if the lead resistance is nulled out.
In the latter case, zero compensation for lead and internal resistance
contributions may limit full-scale readout. 2-wire measurements above 1.5 Ω
should be made using higher ranges.

4-Wire Measurements

With a 4-wire connection the lead resistances have negligible effect and only the
value of Rx is displayed. See Figure 6.

Figure 5. 2-Wire Measurements

Figure 6. 4-Wire Measurements

adj091f.emf

adj092f.emf

36

Reference Multimeter and 8 ½ Digit Multimeter

Functions

4-Wire High-Resistance Measurements

When you make very high resistance measurements (above approximately
1 MΩ) a metal screen can be wrapped around the resistor to reduce noise,
usually caused by charge injection. Connect the GUARD terminal to the screen
to intercept leakage with the screen (in parallel with the unknown resistor). The
resistor under test should not be grounded as this will make the measurement
have greater noise. See Figure 7.

Figure 7. 4-Wire High-Resistance Measurements

adj093f.emf

4-Wire Resistance Zero

For accurate resistance measurements it is essential that a correctly connected
zero source be used when you do an Input Zero operation before you make a
series of measurements. The preferred arrangement shown in Figure 8 ensures
that thermal and induced EMF effects, and bias current effects, associated with
the Product and the measurement cables are eliminated.

Two precision 4-wire short accessories are supplied. See Accessories. Fitted
over the INPUT HI, INPUT LO, SENCE HI and SENCE LO terminals these
provide a convenient means of zeroing the Product inputs at the terminals. Use
of the 4-wire short device at the Product terminals does not address potential
sources of error within measurement cables.

Figure 8. 4-Wire Resistance Zero Measurements

adj094f.emf

37

8588A/8558A

Operators Manual

Ω

Guard

In the Resistance function, with Ext. Guard selected (see also Input Terminal
Selection), the GUARD terminal functions as an Ω Guard. Use the GUARD

terminal as Ω Guard and the Ω Guard feature can make ‘in-circuit’ resistance
measurements by guarding out parallel resistance paths. This results in only the
value of Rx being shown.

Similarly, use Ω Guard to reduce the settling time if Rx is shunted by any
capacitance and a suitable tapping point is available. The connections for making

Ω Guard measurements are shown in Figure 9. Push  then select Ext.
Guard to toggle external guard between ON and OFF. See Table 10.

Figure 9. Ohms Guard Measurements

Table 10. Minimum Guard Resistances

Range Minimum value for Ra and Rb

1 Ω, 10 Ω 100 Ω

100 Ω 1 kΩ

1 kΩ, 10 kΩ, 100 kΩ, 1 MΩ 10 kΩ

10 MΩ, 100 MΩ, 1 GΩ, 10 GΩ 100 kΩ

Providing that Ra and Rb are greater than the values shown in Table 10, and the
Ω Guard resistance (Rg) is <1 Ω, the actual value can be calculated from the
displayed value Rd by:

Rx = Rd x (1 + E)

Deviation fraction ‘E’ can be found within 1 % by the simplified formula:

E = (Rd x Rg) / (Ra x Rb)

(Where Rg is the Ω Guard lead-resistance from the junction of Ra and Rb)

adj095f.emf

38

Reference Multimeter and 8 ½ Digit Multimeter

Functions

Example:
If Rd = 100 Ω, Rg = 1 Ω, Ra = Rb = 10 kΩ, then the value of E is given by:

E = (100 x 1) / (10 k x 10 k) = 10 -6 (1 ppm of readings)

The value of Rx is thus given by:

Rx = 100 x (1 + 10 -6) Ohms,

= 100.0001 Ohms

Internal Guard Connections

External Guard not selected (OFF): In the Ohms or PRT functions, the GUARD

terminals on the front and rear panels are isolated from each other and from any
internal connection. The internal guard shields and tracks are connected directly
to the internal 0 V.

External Guard selected (ON): In the Ohms or PRT functions, selecting the

External Guard provides an Ohms Guard function. The internal guard shields,
tracks, and the selected front or rear GUARD terminal are connected to the
internal 0 V. See Figure 10. See Input Terminal Selection for more information.

Digitize

Figure 10. Internal Guard Connections

adj062f.emf

The Digitize function captures a continuous analog signal in a sequence of
discrete time intervals. One way to view the data is to use the Product’s Analyze
Frequency Domain Charting feature. With other post-processing using an
external program, the captured data can be turned into even more useful
information. An example is to transform the captured data by Fourier transform,
to determine the relative phase angle and magnitude of harmonically related
components in a signal. The Product has extensive triggering and timing
capabilities to allow precise capture of the data for the Fourier transform. See
Triggering Measurements.

All aspects of triggering a data acquisition in the Digitize function are controlled
by the Product Trigger subsystem. See Triggering Measurements first to use
Digitize to its maximum capability. There is a significant difference in the Trigger
subsystem between Digitize and the other functions. The free-run trigger state,
Initiate Continuous ON, is not supported in Digitize. When you push , the
Product Trigger subsystem is set to the idle state, Initiate Continuous OFF, and
any current trigger cycle is aborted.

39

8588A/8558A

Operators Manual

Note

Data acquisition in Digitize starts from the front panel when you push
 or by a remote command. You cannot start an acquisition
with .  is normally used to toggle the Trigger
subsystem from the free-run state (Initiate Continuous ON) to the
idle state (Initiate Continuous OFF). Digitize does not have a free­run trigger state.  can be used to stop an acquisition if
desired.

Digitize uses a high-speed analog-to-digital converter to capture input signals.
The Digitize function has a tracking circuit that follows the analog input. When a
trigger occurs, the value on the tracking circuit is held, and converted to a digital
value. The conversion process takes about 85 ns. Once the conversion is
complete, tracking of the signal recommences. Another 115 ns tracking is
required before the analog-to-digital converter is ready for another trigger. See
Figure 11.

iei191.png

Figure 11. Digitize Track and Convert Timing

The Digitize Aperture is defined as the time difference between the occurrence of
the trigger and time when the tracking value is held. The default is 0 ns, which
means the analog value is held at 0 ns the time the trigger occurs. (In actuality,
there are latencies in the circuit, up to 10 ns.) The entire process for one reading
is 200 ns, which gives a maximum Digitize trigger rate of 5 MHz. Aperture
settings other than 0 ns uses an averaging algorithm. A 200 ns Aperture setting,
for example, averages two samples taken 200 ns apart. In this case, it takes an
additional 200 ns to process the data, giving an acquisition period of 200 ns +
200 ns, or 400 ns. Examples of different Aperture settings and sample values are
shown in Figure 12.

40

Reference Multimeter and 8 ½ Digit Multimeter

Functions

iei190.png

This figure shows a changing signal level (0.5 μV to 1.9 μV) vs time. If the Aperture is set to 0 ns, the
sample value is 0.5 μV and the sample was captured at the time of the trigger. If the Aperture is set to
200 ns, the sample value is (0.5 μV + 0.9 μV)/2 or 0.7 μV, which is 200/2 or 100 ns after the trigger. If the
Aperture is set to 400 ns, the sample value is (0.5 + 0.9 + 1.3)/3 or 0.9 μV, which is 400/2 or 200 ns after
the trigger. If the Aperture is set to 600 ns, the sample value is (0.5 + 0.9 + 1.3 + 1.7)/4 or 1.1 μV, which
is 600/2 or 300 ns after the trigger.

Figure 12. Aperture Settings and Sample Values

41

8588A/8558A

Operators Manual

Digitize Menu

Push  to access the Digitize menu. All of the parameters on the screen are
informational and are set with the digitize softkeys and . See the screen
below:

iei032.png

Number of Samples is a key parameter to change when you use Digitize. The
default is 1, and is changed through the Trigger Setup menus. In most
applications, change Number of Samples by setting the Triggers/Arm (Count) in
the Trigger Setup menu. There may be situations that require setting the count in
the other two trigger layers, Arm2 and Arm1 to values other than 1. If the other
layers are changed, the Number of Samples in Digitize is the product of all the
count settings in each trigger layer. For example, setting the Trigger layer
Triggers/Arm (Count) to 3 and the Arm2 Count to 1e6 gives a Number of
Samples of 3e6. The maximum Number of Samples is 10e6 with Time Stamps
Off, and 5e6 with Time Stamps On.

Digitize has these softkeys:

 (V or I): Selects the voltage or current signal path. Volts uses the HI and
LO terminals. Amps uses the A and LO terminals.

 (Range): Selects the range of the signal path. Voltage ranges are
100 mV, 1 V, 10 V, 100 V, and 1 kV. Current ranges are 10 μA, 100 μA, 1 mA,
10 mA, 100 mA, 1 A, 10 A, and 30 A (8588A only) from the front inputs. If the
rear inputs are used, the 10 A and 30 A ranges are not available.

 (Coupling, Zin): For volts, selects the input coupling and input
impedance. Available choices are DC, Auto; DC, 1 MΩ; DC, 10 MΩ; AC, 1 MΩ;
and AC 10 MΩ. For Amps,  selects the input coupling, either DC, Auto; or
AC, Auto. There may be specification differences based on the input coupling
and impedance. See Specifications.

42

Reference Multimeter and 8 ½ Digit Multimeter

Functions

 (Measure Setup): A 100 kHz or 3 MHz low pass filter or Filter Off can be
selected and the aperture is set in this setup menu. The low pass filter is inserted
after the signal conditioning and before the high-speed analog-to-digital
converter. The default is 3 MHz. The aperture of the analog-to-digital converter
has a default of 0 ns, so the analog-to-digital converter digitizes the input at the
time of the trigger. The entire process for one reading is 200 ns, which gives a
maximum trigger rate of 5 MHz. The aperture can be set from 0 ns to 3 ms in
200 ns increments up to 1 ms, and 100 μs increments from 1 ms to 3 ms.

Digitizing Examples

1) This simple example captures 1 000 000 readings and then shows the
resulting signal using Analyze. From a power-on default state:

1. Push .

2. Select the 10 V range with the  (Range) softkey.

3. Push  and set Triggers/Arm (Count) to 1000000.

4. Push  to return to the Digitize menu.

5. Apply a 10 V, 10 Hz sinewave signal to the input.

6. Push  to capture the signal.

7. Push  to see two cycles of the captured signal.

2) Capture 10 000 samples of a 10 Vrms 10 kHz signal with at least 0.01 %
accuracy:

Considering the Nyquist theory for post process transformation of data into
the Frequency domain, you need to sample at least twice the frequency of
the signal, you should set the sample rate to 20 kHz or higher. Referring to
the Product specifications, 50 kHz meets the accuracy requirement and is
faster than twice the signal, so this is a good choice. See Specifications. To
set the Trigger subsystem, push (). You can indirectly set the
sample rate with the Trigger subsystem TIMER. If the TIMER interval is
longer than other delay settings in the Trigger subsystem, the trigger rate is
the reciprocal of the TIMER interval. The aperture time should be less than
the sample period to avoid “trigger too fast” errors. "Trigger too fast" errors
can result in an unexpected number of readings that different from the trigger
count setting. In this example, set the aperture period to 10 μs, ½ the period
of 50 kHz. Aperture is set with  (Measure Setup) in the Digitize top
menu. See Table 11.

43

8588A/8558A

Operators Manual

Push 

Table 11. Digitize Example 2

Action Comment

Aborts any current trigger cycle. Trigger
subsystem placed in the Idle state, INIT:CONT
OFF.

If not already in voltage mode, push  (V or
I) to select Voltage.

Push  (Range) and select the 10V range.

Push  (Measure Setup) and set a 10 µs
aperture and the low pass filter to OFF.

Push  (Coupling, Zin) and select the
required input coupling and impedance.

Connect the signal to be sampled to the active
input terminals.

Push 

Push  (Reset to Defaults) to reset the
Trigger subsystem to the default settings

Aperture selection is a compromise between
noise and bandwidth, which affect the overall
accuracy. The input signal is averaged during the
sample time. If the magnitude of the signal
changes during the aperture a magnitude error
results. While noise increases as aperture
decreases, magnitude error decreases. The
Aperture time should be less than the sample
period to avoid trigger too fast errors.

For voltage ranges ≤10V, use DC, Auto. For the
100V and 1000V ranges, use DC, 1M for best
performance.

Done at this point to provide time for the signal
conditioning circuits to stabilize.

The default settings pertinent to this example are

ARM2:SOURce IMM

ARM2:COUNT 1

ARM2:ECOUNT 1

ARM1:SOURce IMM

ARM1:COUNT 1

ARM1:ECOUNT 1

44

Reference Multimeter and 8 ½ Digit Multimeter

Functions

Table 11. Digitize Example 2 (cont.)

Action Comment

Use the navigation keys and push  to set
the first row, trigger event, to Timer. Push 
to return to the top of the Trigger Setup menu and
ensure that the Trigger Event is set to Timer.

Use the navigation keys to move to the second
row labeled Timer, and set the Timer to 20 μS.

Push  to return to the top of the Trigger
Setup menu.

Select Triggers / Arm (Count) and set to 10,000.

Set Delay to zero.

Set Holdoff to 0 s.

Push  twice Returns to the Digitize function.

Push  to start the acquisition.

The sample rate is equal to 1/Timer, or 50 kHz

Count determines the number of samples that will
be taken. The count of 10 000 will cause 10 000
samples to trigger before the Trigger subsystem
returns to the Idle state.

Setting Delay to zero ensures that if Delay and
Holdoff settings add to more than the trigger
period, they would cause the trigger rate to be
slower than 1/Timer.

The holdoff period occurs after the acquisition
starts but if longer than the trigger interval, it
causes the trigger rate to be slower than 1/Timer.

The Product captures 10,000 readings and saves
data to memory.

When the capture and transfer bars turn from white to green the data has been
captured and can be analyzed with or exported to an external memory
device for analysis elsewhere. To export the data to a file, push  to
access data transfer options. See the screen below:

iei033.png

45

8588A/8558A

Operators Manual

3) Capture 4096 samples of a 1 Vrms, 4 kHz wave form with a 5 μs acquisition
period and at a rate controlled by an external 10 kHz trigger wave form. See
Table 12.

Table 12. Digitize Example 3

Action Comment

Push .

If not already in voltage mode, push  (V or
I) to select Voltage.

Push  (Range) and select the 1 V range.

Push  (Measure Setup) and set a 5 µs
aperture and a low pass filter if required. When
done, push  to return to the main Digitize
menu.

Push  (Coupling, Zin) and select the
required input coupling and impedance.

Connect the signal to be sampled to the active
input terminals.

Push .

Push  to reset the Trigger subsystem to the
default settings

Aborts the current trigger cycle. Trigger
subsystem placed in INIT:CONT OFF

Aperture selection is a compromise between
noise and bandwidth. The input signal is
averaged during the sample time. If the
magnitude of the signal changes during the
aperture a magnitude error will result. While noise
increases as aperture decreases, magnitude error
decreases. The Aperture time should be less than
the sample period to avoid a/d acquisition errors.

For voltage ranges 10 V or less, use DC, Auto.
For the 100 V and 1000 V ranges, use DC, 1M for
best performance.

This provides time for the signal conditioning
circuits to stabilize.

The default settings pertinent to this example are

ARM2:SOURce IMM

ARM2:COUNT 1

ARM2:ECOUNT 1

ARM1:SOURce IMM

ARM1:COUNT 1

ARM1:ECOUNT 1

46

Push  to set the Trigger Event to External
in the Trigger Setup menu.

Reference Multimeter and 8 ½ Digit Multimeter

Functions

Table 12. Digitize Example 3 (cont.)

Action Comment

Check that the second row shows the type and
polarity of trigger edge required. If not, highlight
row two and push  to change the settings.

Push  or  to highlight the Triggers per arm
(Count) setting and enter 4096.

Set Delay to zero.

Set Holdoff to zero.

Default is TTL, Negative.

The Trigger subsystem Arm 2 and Arm1 layer
trigger events are automatically satisfied since
they are set to their defaults, Immediate. The
Trigger layer accepts 4096 external triggers
before it returns to the Idle state.

Setting Delay to zero minimizes the delay
(latency) between the trigger edge and start of the
acquisition. This is important if the digitized data
is used to determine the phase-angle relationship
of the signal to the trigger.

Holdoff prevents Trigger Too Fast errors if the
Trigger subsystem is free running without other
delays. In this case, timing is controlled by an
external signal so Holdoff should be set to zero.

Push  once or  twice Returns to the Digitize function

Connect the trigger signal to the BNC connector
on the rear panel.

Push  to start the acquisition.

The system is now ready to begin data capture

The Product captures 4,096 readings and saves
data to memory.

When the progress bar has turned from white to green the data has been
captured and can be analyzed using or exported to an external device for
analysis elsewhere. Push  to access data transfer options. See the
screen in Digitizing Examples.

47

8588A/8558A

Operators Manual

More

Push  to access these functions:

•  (Capacitance)

•  (RF Power)

•  (Frequency)

•  (DCI Ext Shunt)

•  (More) opens these additional functions:

o  (ACI Ext Shunt)

o  (PRT)

o  (Thermocouple)

Note

After you push  (More), DCI Ext Shunt is made available by
. Push  (More) additional times to cycle the choices
again starting with (Capacitance).

Capacitance (8588A only)

To avoid possible damage to the Product or to the equipment
under test, disconnect circuit power and discharge all high­voltage capacitors before you measure capacitance. Use the DC
Voltage function to confirm that the capacitor is discharged.

Push  and then  (Capacitance) to use the Capacitance Measure
function. This function provides 2-wire measurements that use the V INPUT HI
and LO input terminals. With polarized capacitors, connect the positive side to
LO and the negative side to HI (VΩ|) as shown in Figure 13.

WCaution

48

Figure 13. Connection for Capacitance

iei188.png

Reference Multimeter and 8 ½ Digit Multimeter

More

The ranges available are Auto, 1 nF, 10 nF, 100 nF, 1 μF, 10 μF, 100 μF, 1 mF,
10 mF, and 100 mF when using the Capacitance Normal I mode. The LoI mode
is limited to Auto, 1 mF, 10 mF, and 100 mF ranges.

Capacitance Menu

This section explains the Capacitance menu.

 (Range): Each of the Capacitance ranges can be manually selected or
select Auto to put Capacitance into autorange. Make the range selection with the
softkeys or use the navigational keys to highlight the selection and push .
Push  to return to the start page of the menu.

 (Resolution): Capacitance has resolution 4 digits or 5 digits. Select the
resolution with the softkeys or use the navigational keys to highlight the selection
and push . Push to return to the start page of the menu.

 (LoI): Two different current levels are available to make capacitance
measurements. LoI OFF is the default, and makes measurements in all of the
ranges (1 nF to 100 mF). LoI uses a lower stimulus current and is limited to three
ranges (1 mF to 100 mF). LoI ON may be useful if the default current causes a
calibrator’s capacitance function to overload in these ranges. See Specifications.

Measure Capacitance

The Product uses a dc charge/discharge method to measure capacitance, based
on the formula C = I dV/dt. One use for the Capacitance function is to measure
the output of multi-function calibrators, for example the Fluke 5522A. Connect the
Product INPUT HI to the calibrator OUTPUT HI and the Product INPUT LO to the
calibrator OUTPUT LO. With polarized capacitors, connect the positive side to
LO and the negative side to HI (VΩ|) as shown above in Figure 14. Capacitance
is a 2-wire measurement and the Product reading includes the capacitance of the
connecting leads. Compensate for the connecting leads by using the Zero
function. To do so, connect one end of the connecting leads to the Product, and
the other end to an open circuit on a non-conducting work surface. Push 
and select  (Zero Range) or  (Zero Function) as appropriate. The
Zero function can accommodate approximately 200 pF of lead capacitance so
Fluke Calibration recommends the use of short, low capacitance connecting
leads. The standard lead set capacitance is less than 200 pF so this will be
adequate.

Figure 14. Capacitance Measurements Connection

The standard lead set can be used for most capacitance measurements.

Iei340.emf

49

8588A/8558A

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RF Power (8588A only)

An RF power sensor can be connected to the Product EXT PORT to make RF
power measurements.

Instructions to connect a power sensor to the Product and to a DUT are given
below. Do not make connections before you read all of the Cautions contained in
these instructions.

WCaution

To prevent equipment damage, follow the instructions below
before you connect the power sensor to the Product or a Device
Under Test (DUT).

WCaution

The optional power sensor(s) contain components which can
be destroyed by electrostatic discharges. To prevent this, never
touch the sensor RF connector inner conductor and never open
the sensor. Never exceed the sensor maximum RF power limit.
Even brief overloads can destroy the sensor.

WCaution

The Product front-panel Power Sensor connector interface is
only for use with compatible power sensors. To prevent
damage to the Product, no other connection is permitted.

Fluke Calibration supplies a NRP type sensor as an option.

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RF Power Menu

Push  and then (RF Power) to enable the RF Power function. If a RF
sensor is not connected, a connection message at the bottom of the screen
prompts you to do so. This section explains the RF Power menu. See the screen
below:

iei034.png

When a compatible sensor is plugged into EXT PORT, the top of the RF Power
menu shows the sensor type and serial number. The lower part of the screen has
two parameters that can be changed with the navigation keys and numeric
keypad:

Frequency: Power readings are based on the frequency of the signal to be
measured. After the sensor is plugged in, frequency is set to a default of 50 MHz.
Use the navigation keys or the numeric keypad to change the frequency in that
field. The allowable frequency values are determined by the connected sensor
and generally include 0 Hz.

Reference level: Use the reference level to make relative measurements. The
power-on default is -99 dBm. To change the reference level, use the navigation
keys to highlight and select Reference level. The range of reference level is
99 dBm to -99 dBm. When other units are selected, the reference level range is
shown in Table 13. The reference level can also be set by pushing  (Last
Reading).

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8588A/8558A

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RF Power Softkeys

Table 13. Setting Limits for Reference Level Units

Parameter Min Max

dBm -99 +99

Watts 100.03 fW 9.9997 MW

Vrms 2.2364 μV rms 22.358 kVrms

Vpk-pk 6.326 μVpk-pk 63.24 kVpk-pk

dBμV -6.991 dBμV 206.988 dBV

This section explains the RF Power softkeys.

 (Reading): Chooses between Absolute or Relative. The default is
Absolute. Relative shows measurements relative to the reference level. In
relative, the displayed reading is the absolute reading minus the reference level.

 (Last Reading): Pushing  sets the reference level to the reading
that is currently displayed. The Last Reading feature is useful to check the
flatness of a generator relative to a reference frequency output.  works the
same way in both absolute and relative modes, that is, it takes whatever is
displayed and makes that the reference level.

 (Average): Determines the averaging factor applied by the RF power
sensor. When set to Auto, the power sensor continuously determines the
averaging factor which depends on the power level with a maximum settling time
of 4 seconds for the sensor’s averaging filter. Alternatively, a specific averaging
factor value between 1 and 32768 in a 2

n sequence may be selected. Use the

navigation keys to select the averaging factor.

Use the cursor keys or the softkeys to choose:

• Auto

• 1

• 2

• 4

• 8

• 16

• 32

• 64

• 128

• 256

• 512

• 1024

• 2048

• 4096

• 8192

• 16384

• 32768

 (Units): Readings with these units: dBm, Watts, Vrms, Vp-p and dBμV.
The units are changed with the navigation keys or corresponding softkeys. The
default unit is dBm. The Product keeps the last units used until the Product is
powered off.

Note

Display of readout values in linear units of watts or volts may use W,
mW,

μ

W or V, mV, or μV depending on the measured value.

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Connect a Power Sensor to the Product

To connect the power sensor interface cable multiway connector to the Product:

1. Remove the plastic cap from the cable-end connector and save it for future
use.

2. Connect the multiway connector to the EXT PORT on the Product. Push
firmly on the multiway connector until it latches. See Figure 15.

The presence of a sensor at the Ext. Port is automatically detected. Only
compatible sensor models are recognized. There may be a slight delay between
the connector insertion and completion of the automatic detection process.

Figure 15. Connect a Power Sensor to the Product

iei337.jpg

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Connect a Power Sensor to a Unit Under Test

WCaution

To prevent damage to the Product:

• Never exceed the maximum RF power limit. Even brief
overloads can destroy the sensor. See Specifications.

• Do not touch the RF connector inner conductor. The power
sensor contains components which can be destroyed by
electrostatic discharges.

To connect a power sensor to a DUT:

1. Remove the plastic protection cap from the sensor RF input connector and
save it for future use.

2. Ensure the DUT output is either OFF or at a safe RF level, and then connect
the sensor RF input connector to the output of the DUT.

3. For a NRP sensor fitted with a 2.92 mm RF connector, torque the connector
to 0.49 Nm (4 in-lb) with a torque wrench. If another compatible sensor with a
different RF connector type is used, tighten to a torque appropriate for that
type of connector.

The NRP power sensors have a type of ball-bearing RF connector.
The friction with this design is considerably less than with
conventional RF connectors, and a repeatable connection is ensured
even at relatively low torques. When tightened to the correct torque,
the sensor body may still rotate. Do not try to prevent this by
increasing the torque above the permissible value or by attempting
to tighten the connection by turning the sensor body.

Set the Measurement Frequency

For valid measurements, the frequency setting must correspond to the frequency
of the signal to be measured. To set the frequency, use the navigation keys to
select that field. Enter the frequency with the numeric keypad. The allowable
frequency values are determined by the connected sensor and generally include
0 Hz.

Note

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Frequency Counter

From the More menu, push  (Frequency) to use the Frequency Counter
measuring function. The Frequency Counter measuring function defaults to using
the rear panel BNC connector to make frequency measurements. The input is
selected using  (Measure Setup). When in ACV, the V INPUT HI and LO
terminals are used to measure frequency of an ACV signal, and the rear BNC is
de-selected. When in ACI, the A INPUT HI and LO terminals are used to
measure frequency of an ACI signal, and the rear BNC is de-selected.

The default Frequency Counter measuring screen is shown below. The input field
shows which connector is selected to measure the input signal. The lower status
field shows coupling (ac or dc) and the counter gate time (100 μs to 1 s). See the
screen below:

Frequency Counter Menu

This section explains the Frequency Counter menus when the rear BNC is
selected.

 (Gate): selects the counter gate time: 100 μs, 1 ms, 10 ms, 100 ms, or
1 s. Use the navigation keys or the appropriate softkeys to select. The gate times
affect the Counter resolution as shown in Table 14. In Frequency, gate times are
not affected by the input channel or RMS filter settings in ACV or ACI. When you
use frequency as a secondary reading, gate times are affected by the RMS filter
settings in ACV or ACI. See ACV Menu and ACI Menu.

iei011.png

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8588A/8558A

Operators Manual

8 digits 1 s

7 digits 100 ms

6 digits 10 ms

5 digits 1 ms

4 digits 100 μs

Table 14. Equivalent Resolution/Gate Setting

Counter Display Resolution Counter Gate

 (Parameter): Allows display of either frequency (default) or period.

 (Z in): Allows selection of either 50 Ω (default) or High impedance

(10 kΩ).

 (Measure Setup): Shows the screen below:

56

iei012.png

Coupling: Sets the input path to either  (AC) (default) or  (DC).

Bandwidth Limit: Can be set to  (ON) or  (OFF). When Zin is set to

50 Ω, with Bandwidth Limit ON, the bandwidth (-3 dB) is 1.5 MHz. When Zin is
set to High, with Bandwidth Limit ON, the bandwidth (-3 dB) is 1 MHz. The
bandwidth (-3dB) is 100 MHz, with Bandwidth Limit OFF and Zin set to 50 Ω.
With Zin set to High, and using an external in-line terminator on the rear BNC
Freq IN, the bandwidth is also 100 MHz.

Reference Multimeter and 8 ½ Digit Multimeter

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Threshold: Can be set to -5 V to +5 V with 0.1 V setting resolution when the
BNC input is selected. Default is 0.0 V.

Input path: Use to select the frequency counter input path. The choices are:

 (Rear BNC): When you use the Rear BNC input, the minimum frequency
for any given gate time is four times higher than expected. For example, a 1 s
gate time has a minimum frequency measurement of 4 Hz.

 (ACV Signal): Uses the V INPUT HI and LO terminals.

 (ACI Signal): Uses the A INPUT HI and LO terminals. Selecting 

(ACV Signal) or  (ACI Signal) changes the main Frequency screen to that
shown below. This screen has an additional softkey,  (Range). There is no
autorange for ACV and ACI signals. Only discrete voltage or current ranges can
be selected. The available ACV ranges are 10 mV, 100 mV, 1 V, 10 V, 100 V and
1 kV. The available ACI ranges are Auto, 10 μA, 100 μA, 1 mA, 10 mA, 100 mA,
1 A, 10 A, and 30 A. See the screen below.

iei035.png

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8588A/8558A

Operators Manual

Measure Frequency

When Frequency is measured with the rear BNC connector, use shielded coaxial
leads. See Figure 16.

Figure 16. Frequency Measurement with Rear Input

iei341.jpg

When measuring frequency using the V INPUT HI and LO terminals, use the
same leads that you use in ACV. See AC Voltage. When you measure frequency
using the A INPUT HI and LO terminals, use the same leads that you use in ACI.
See AC Current.

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DCI Ext Shunt (8588A Only)

The DCI Ext Shunt function measures the dc voltage across the shunt and shows
the calculated current, taking into account specific characteristics of the external
shunt. Push  then  (DCI Ext Shunt) to use the DCI Ext Shunt
function. With DCI Ext Shunt, the Product is used with an external dc current
shunt to measure current. The voltage can be shown as a secondary reading.
DCI Ext Shunt is used to augment the measurement capability of the Product
and to calibrate current shunts themselves.

The default external shunt is the Basic and allows quick setup. This shunt always
appears at the top of the list of shunt data with asset number and manufacturer
both represented by "---". Maximum current and resistance value are the only
editable fields for the default basic shunt. See the screen below, which shows the
shunt information line above the calculated current reading:

DCI Ext Shunt Menu

This section explains the DCI Ext Shunt menu.

 (Range): Allows selection of the Auto, 100 mV, 1 V, or 10 V dc ranges.
Auto will autorange between those ranges depending upon input. The input
impedance is 10 MΩ. The internal firmware of the Product calculates and
corrects for shunt loading based on the 10 MΩ input impedance if Shunt
Corrections is set to ON under Measure Setup.

 (Resolution): The default resolution is 6 Digits. Other choices available
are 4, 5, and 7 Digits.

 (2

nd

Reading): The actual dc voltage or additional Power Uncertainty can

be shown as the secondary reading. Secondary reading is not shown if OFF is
selected. Power Uncertainty is the symmetrical uncertainty due to the self­heating of the shunt based on the current applied and power reference level
setting for the external shunt. See Calculation of the Power Uncertainty.

 (Select Shunt): This menu opens a number of other menus that provide
access to specific current shunts and their characteristics.

iei013.png

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8588A/8558A

Operators Manual

Select Shunt Submenu

 (Measure Setup): Aperture/PLC sets the integration time of the A to D
converter using the navigational keys, much like Measure Setup in DCV. The
choices are:

• Auto

• Auto Fast

• Manual

When you select Manual, use the softkeys and the numerical keypad to edit the
integration time by PLC and Time. The smallest time aperture is 0 seconds with
200 ns increments and has an upper time limit of 10 seconds. The smallest
aperture that can be set by PLC is 0.01. The upper limit is the PLC equivalent of
10 seconds and is determined by the line frequency setting in the Instrument
Setup menu.

Shunt Corrections: When set to ON (Power-on default), the calculated current
reading is based on the external shunt value and the shunt loading from the
10 Mohm input impedance of the Product. Note that if set to OFF, an Instrument
reset (Instrument Setup > Reset Instrument) retains the OFF setting. If the
Product is power cycled, Shunt Corrections is always set to ON.

The section explains the Select Shunt submenu.

 (Page Down) and  (Page Up): Allows you to scroll through all of the
current shunts stored in the Product.

 (Sort By): Allows you to sort by Asset number, Serial number or Max A.
Push  to cycle through the three choices. Note that the Basic shunt is
always at the top.

 (Delete Shunt): Allows you to delete the selected shunt (indicated by the
darkened circle on the left). A user prompt shows before actual deletion.

 (Manage Shunts): Allows you to edit specific characteristics of the shunt
as well as adding a new shunt.

Manage Shunts Submenu

The Manage Shunts submenu is explained in this section. Enter the appropriate
information for each of these fields with the navigation keys and numeric keypad.

• Asset number (shown as the first field on the shunt information line of

the main DCI Ext Shunt screen)

• Manufacturer (displayed as the second field on the shunt information

line)

• Model

• Serial Number

• Resistance value: Use the numeric keypad and  to input the

resistance value of the shunt, for example from the most recent
calibration certificate. Resistance value is shown as the fourth field in the
shunt information line.

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• Maximum current: Use the numeric keypad and  to input the

maximum current that can be applied to the shunt without causing a
resistance value change. Maximum current is displayed as the third field
in the shunt information line.

• Power ref. level: Enter the current level used when calibrating the shunt

resistance value.

• Power coefficient: Enter the power coefficient of the shunt, in μA/A.

The Power ref level and Power coefficient entries are used to calculate the
additional uncertainty of the displayed current due to self-heating of the
shunt. The Power uncertainty is shown as an integer value between 0 μA/A
and 999,999 μA/A, and does not affect the calculated current. See the screen
below.

Calculation of the Power Uncertainty

Power uncertainty = Power coefficient x { 1 - (Measured current/Power ref

2

level)

}

See the screen below:

iei014.png

Push  (Save as new) to save as a new DCI Ext Shunt, or push  to
save as changes to the existing shunt.

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Measure DC Current with DCI Ext Shunt

The DCI Ext Shunt function provides a calculated current reading for a specified
current shunt by measuring the voltage across the shunt. If Shunt Corrections
are OFF, the displayed current is calculated from I = V/R where R is the
resistance of the shunt. If Corrections are ON, the displayed current is calculated
using the parallel resistance of the shunt and the 10 MΩ input impedance of the
DCI Ext Shunt function. Connections are straightforward, as shown in Figure 17.

Similar connection considerations are required for connecting the external shunt
input terminals as for dc current measurement. Use shielded twisted-pair cable to
reduce induced interference signals, and connect GUARD to the source of
common-mode voltage to provide a separate common-mode current path. To
connect the external shunt sense terminals to the Product, use low thermal leads
as in DCV.

DCI Ext Shunt

UHF UHF

F

Vo l t a g e

Figure 17. External DC Shunt Connection

ACI Ext Shunt (8588A Only)

The ACI Ext Shunt function measures the ac voltage across the shunt and shows
the calculated current, taking into account specific characteristics of the external
shunt. Push ,  (More), and then  (ACI Ext Shunt) to use the
ACI Ext Shunt function. With ACI Ext Shunt, the Product is used with an external
ac current shunt. If Shunt Corrections are OFF (under  (Measure Setup)),
the displayed current is calculated from I = V/R where R is the resistance of the
shunt. If Shunt Corrections are ON, the displayed current is calculated taking into
account the shunt AC-DC difference and the input impedance of the ACI Ext
Shunt function. The voltage can also be shown as a secondary reading. ACI Ext
Shunt augments the current measurement capability of the Product and is used
to calibrate current shunts themselves.

ACI Ext Shunt Menu

The section explains the ACI Ext Shunt menu.

 (Range): Allows selection of the Auto, 10 mV, 100 mV, 1 V, or 10 V ac
ranges. Auto autoranges between those ranges depending upon the input. The
input impedance is 10M Ohm in parallel with 80 pF. The internal firmware of the
Product calculates and corrects for shunt loading based on the 10 MΩ / 80 pF
input impedance if Shunt Correction is set to ON.

output

FM

Low Thermal Leads

HI

LO

iei105.emf

62

 (Resolution): The default resolution is 6 Digits. Other choices available
are 4, 5, and 7 Digits.

Reference Multimeter and 8 ½ Digit Multimeter

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 (RMS Filter): Push to select various filters for the rms converter, allowing
measurements down to the chosen filter frequency without degradation of
accuracy and excessive reading variation. One of the filters is always in circuit.
The 40 Hz filter is the default selection at power on. The filter choices available
are 0.1 Hz, 1 Hz, 10 Hz, 40 Hz, 100 Hz, and 1 kHz. The filter setting determines
the reading rate in ACI. See Specifications. Use the softkeys or the navigational
keys to highlight the selection and then push . Push  to return the
Product to the previous menu.

 (Select Shunt): This menu opens up a number of submenus that provide
access to specific current shunts and their characteristics. (Measure Setup) of
the ACI Ext Shunt menu provides access to a menu that allows you to change
how measurements are made and what is displayed. See ACI Ext Shunt
Measure Setup Menu.

Select Shunt Submenu

The section explains the Ext Shunt submenu.

 (Page Down) and  (Page Up): Allows you to scroll through all of the
current shunts stored in the Product.

 (Sort by): Allows you to sort by Asset number, Serial number or Max A.
Push  to cycle through the choices.

 (Delete Shunt): Allows you to delete the selected shunt (indicated by the
darkened circle on the left). A confirmation prompt appears before actual
deletion.

 (Manage Shunts): Allows you to edit specific characteristic of the shunt,
as well as adding a new shunt.

Manage Shunts Submenu

The section explains the Manage Shunts submenu, which is similar to the DCI
Ext Shunt submenu mentioned previously.

Push  (Edit AC-DC Differences) to open a menu to enter ac-dc
differences of the current shunt. When using Fluke A40B current shunts, enter
the ac-dc differences at each of the frequency points from the calibration
certificate of the respective shunt. When Shunt Corrections is set to ON (under
 (Measure Setup)), the calculated current reading is corrected using a
linear interpolation of the ac-differences based on frequency. See the screen
below:

iei015.png

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8588A/8558A

Operators Manual

Enter the appropriate information for each of the fields listed with the navigation
keys and numeric keypad.

• Asset number (shown as the first field on the shunt information line of

the main DCI Ext Shunt screen)

• Manufacturer

• Model (shown as the second field on the shunt information line)

• Serial Number

• Resistance value: Use the numeric keypad and  to input the

resistance value of the shunt, for example from the most recent
calibration certificate. Resistance value is displayed as the fourth field in
the shunt information line.

• Maximum current: Use the numeric keypad and  to input the

maximum current that can be applied to the shunt without causing a
resistance value change. Maximum current is displayed as the third field
in the shunt information line.

• Power ref. level: Enter the current level used when calibrating the shunt

resistance value.

• Power coefficient: Enter the power coefficient of the shunt, in μA/A.

The Power ref level and Power coefficient entries show the uncertainty of the
displayed current due to self-heating of the shunt. The Power uncertainty is
shown as an integer value between 0 μA/A and 999,999 μA/A, and does not
affect the calculated current. See the screen below.

Calculation of the Power Uncertainty:

Power uncertainty = Power coefficient x {1 - (Measured current/Power ref level)

Push  to (Save as new) the ACI Ext Shunt, or push  (Save
changes) to save the shunt changes. See the screen below:

2

}

64

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ACI Ext Shunt Measure Setup Menu

The section explains the ACI Ext Shunt  (Measure Setup) menu submenu.

• Signal path coupling: Choose  (AC) or  (DC).

• Secondary Reading: In the ACI function, a secondary reading can be

shown. This menu choices are:

o  (Shunt Voltage)

o  (Frequency)

o  (Period)

o  (Power Uncertainty) Power uncertainty is based on the shunt

input current level, the power reference level and power coefficient.
Power uncertainty is the symmetrical uncertainty due to the self-heating
of the shunt based on the input current level. See Calculation of the
Power Uncertainty.

o  (More) additional Secondary Reading parameters

  (Pk to Pk) (repeated for ease of use)

  (Positive Peak)

  (Negative Peak)

  (Crest Factor)

  (More) Shows:

•  (Positive Peak) (repeated for ease of use)

•  (Negative Peak

•  (Cre

t Factor)

s

)

•  (OFF)

•  (More) returns the to the top level of the Measure Setup

menu.

When Pk to Pk is selected, the Peak to peak method becomes active. (see
below).

• Frequency path coupling: The frequency path coupling can be AC or DC if
the signal path coupling (above) is set to DC. Otherwise, only AC is available.

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8588A/8558A

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• Frequency path bandwidth limit: Choose  (OFF) or  (ON).
Reduces noise in the frequency counter signal path. If there is excessive
noise observed, turn the bandwidth limit ON for signals <70 kHz.

• Counter Gate: Set to:

o 

(Auto)

o  (1 ms)

o  (10 ms)

o  (100 ms)

o  (1 s)

• Peak to peak method: This submenu is made active when the Secondary
Reading is set to Pk to Pk.

o  (Measured) shows the peak to peak as measured in ACI

assuming no particular signal wave form.

o  (Sine)

o  (Square)

o  (Triangle)

o  (Truncated Sine)

 through  specify the signal wave form type that is measured, and
calculates the peak to peak based on the rms value.

If set to:

• Sine, the peak to peak shown is 2 x (square root of 2) x rms.

• Square is 2 x rms

• Triangle is 2 x (square root of 3) x rms

• Truncated Sine is 4.618803 * rms

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Reference Multimeter and 8 ½ Digit Multimeter

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The Square, Triangle, and Truncated Sine selections are useful to measure the
peak-to-peak output of multi-product calibrators like the Fluke 5522A which have
these non-sine wave outputs. See the screen below:

iei017.png

The bottom field, Shunt Corrections ON/OFF determines if the ac-dc differences
for the selected shunt are applied to the displayed current level, and the shunt
loading is accounted for due to the input impedance of the voltage measurement
circuit (10 Mohm in parallel with 80 pF). The main display indicates when
corrections are ON. Note that if set to OFF, an Instrument reset (under
Instrument Setup > Reset Instrument) retains the OFF setting. If the Product
is power cycled, Shunt Corrections is always set to ON.The Product uses a linear
interpolation of the loaded ac-dc differences between the frequency points to
make corrections. See the screen below:

iei019.png

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Measure AC Current with ACI Ext Shunt

The ACI Ext Shunt function provides a calculated current reading for a specified
current shunt. The ACI Ext Shunt function is particularly useful for current shunts
that have corrections for ac-dc differences at different frequencies, like the Fluke
A40B series current shunts. Connections are shown in Figure 18.

Similar connection considerations are required to the external shunt inputs as for
ac current measurement. Use shielded twisted pair cable to reduce induced
interference signals, and connect GUARD to the source of common mode
voltage with the screen, to provide a separate common mode current path. Use
high-quality leads and connections to minimize the burden (compliance) voltage
generated for current measurements and thus, improving measurement
accuracy. Fluke Calibration recommends that leads of the minimum-practical
length be used to reduce lead capacitance, lead inductance, and loop area. The
external shunt sense terminals should be connected to the Product V INPUT HI
and LO terminals using shielded leads.

XW Warning

HIGH CURRENT FLOW

To prevent possible electrical shock, fire, or personal injury:

• Do not exceed the Measurement Category (CAT) rating of
the lowest rated individual component of a Product, probe,
or accessory.

• Only use probes, test leads, and accessories that have the
same measurement category, voltage, and amperage ratings
as the Product.

Note

When you make ac current measurements pay close attention to the
lead impedance, especially lead capacitance at high frequencies on
the lower current ranges. (See Measure AC Voltage)

DCI Ext Shunt

UHF UHF

F

Vo l t a g e

FM

output

Figure 18. ACI Ext Shunt

Low Thermal Leads

HI

LO

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PRT

Push ,  (More), then  (PRT) (platinum resistance
thermometer) to use the PRT measure function. The PRT measure function
provides a temperature readout by measuring the resistance of a connected
PRT. 2 Wire, 3 Wire, or 4 Wire measurements can be made.

PRT Submenu

This section explains the PRT submenu.

 (Probe R

): Selects either a 100 Ω or 25 Ω PRT.

o

 (Resolution): The default resolution is 5 Digits. The other choice is
6 Digits.

 (Probe): Allows selection of 2 Wire, 3 Wire, or 4 Wire PRTs.

 (Units): This softkey opens a menu to select the desired temperature

units, K, °C, or °F.

 (Measure Setup): Provides access to a menu that changes the reading
rate similar to DCV. Choices are Auto, Auto Fast, and Manual.

Measure PRTs

Before you connect a 2- or 3-wire PRT, you must perform Input zero on the
resistance ranges shown in Table 15.

Table 15. Measure PRTs

Probe R

25 Ω 100 Ω, LoI ON, 2-wire

100 Ω

2-wire PRT 3-wire PRT

0

100 Ω, LoI and 1 kΩ, LoI OFF,
2-wire

100 Ω, LoI ON, 2-wire and 4­wire

100 Ω, LoI and 1 kΩ, LoI OFF,
2-wire and 4-wire

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8588A/8558A

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Note

4-wire PRT uses True Ohms so zeroing is not required.

Connect the PRT probe to the Product in the same way as when making
resistance measurements, using the appropriate connection shown in Figure 19.
Select the corresponding 2-, 3-, or 4-wire probe type using the (Probe)
softkey. Fluke Calibration recommends that Ext. Guard is ON (, 
(Ext. Guard)).

70

Figure 19. PRT Connections

Note

The 3-wire PRT connection is actually a 4-wire measurement, and
requires a short between the low terminals as depicted in Figure 19.

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Reference Multimeter and 8 ½ Digit Multimeter

Thermocouple

Thermocouple

The Thermocouple Measure function provides 2-wire measurements that use the
V INPUT HI and LO terminals, converting dc voltage to temperature. Push
,  (More), then (Thermocouple) to use the Thermocouple
Measure function.

Thermocouple measurements require an external cold junction compensation.
The types of thermocouples supported are J, R, E, N, U, C, L, T, B, K, and S.
The Product uses the 100 mV dc range to make all thermocouple
measurements.

Thermocouple Menu

 (Type): Push this softkey to see the thermocouple choices. Make the
thermocouple type selection with the softkeys or use the navigational keys to
highlight the selection and the push . The Product has built-in tables that
convert the measured voltage to temperature based on the thermocouple type
chosen.

 (Resolution): The default resolution is 5 digits. The other choice is
6 Digits.

nd

 (2

nd

reading.

2

reading): Select ON to show the actual dc voltage measured for the

 (Units): This softkey opens a menu to select the desired temperature
units, K, °C, or °F.

 (Measure setup): Provides access to a menu that allows you to change
the reading rate similar to DCV. Choices are Auto, Auto Fast, and Manual.

Measure Thermocouples

Thermocouples are widely used for measuring temperature over a wide range,
with rapid response and no self-heating. The Thermocouple function can be used
to calibrate actual thermocouples themselves or to calibrate the electronic
thermocouple output of thermocouple simulators like those found in the Fluke
5522A Multi-Product Calibrator. Both of these applications require the use of an
external reference junction, often referred to as the cold temperature junction.

A thermocouple in general, shown in Figure 20, consists of two wires of dissimilar
metals joined together at one end, called the measurement or “hot” junction. The
other end, where the wires are not joined, is connected to the Product V INPUT
HI and LO terminals using copper wire. A reference junction (also called the
“cold” junction) must be provided between the thermocouple metals and the
copper wires.

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Thermocouple

Metal A

Wiring to Signal

Conditioning

Circuitry

Metal B

Measurement

Junction

Figure 20. Thermocouple

Reference

Junction

iei107.emf

The temperature of the thermocouple cold junction must be known to get an
accurate absolute temperature reading from a thermocouple simulator. Using a
commercially-available zero-point dry-well as the cold junction, Figure 21 shows
the connections required between the Product and the DUT, an electronic
simulator in the Fluke 5522A.

72

Figure 21. Thermocouple Connection

iei338.jpg

Reference Multimeter and 8 ½ Digit Multimeter

Thermocouple

In this example, the Fluke 5522A simulator and the Product are both set to a J­type thermocouple (constantan and iron). You must use the correct J-type
hookup wire and connector between the DUT and the cold junction. The
connection from the cold junction to the Product must be with copper wire.
Instead of the zero-point dry-well, a dewar with an ice/water slurry mixture can
also be used. For the best accuracy, and to get good test-uncertainty-ratios
(TURs) against the most demanding thermocouple simulators, use an external
reference thermometer to characterize the Fluke 9101 or ice/water slurry mixture.

The connections to calibrate actual thermocouples also requires an external cold
junction. Use a setup that uses a zero-point dry well as in Figure 21, or make an
external cold junction with a dewar and ice bath as in Figure 22. A J type
thermocouple (constantan and iron) is shown. Copper wires are used to connect
from the cold junction to the Products V INPUT HI and LO terminals. The ice bath
reference in this example is comprised of a dewar with an ice/water slurry
mixture. See Figure 22.

Figure 22. Thermocouple Circuit to Calibrate J-type Thermocouple

iei108.jpg

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Features

Input Terminal Selection

The Product has front and rear INPUT terminals. Push  within any function
to open the various input configurations. Softkeys  to  configure the
terminals.

XWWarning

To prevent possible electrical shock, fire, or personal injury, do
not apply more than the rated voltage, between the terminals or
between each terminal and earth ground.

 (Terminals): Is used to select which terminals are in use. Choices are:

• Front: Selects the front terminals only for all inputs.

• Rear: Selects the rear terminals only for all inputs.

• Scan: Front – Rear: Measurements are taken from the front terminals and

then the rear terminals to produce the displayed result, which is the difference
between the measurements from the front and rear terminals.

• Scan: Front / Rear: Measurements are taken from the front terminals and
then the rear terminals to produce the displayed result, which is the ratio of
the front measurement to the rear measurement.

• Scan: (Front – Rear) / Rear: Readings are taken from the front terminals
and then the rear to produce the displayed result. This is the normalized
‘deviation’ value.

• Isolated: When enabled, the Product is in a state of isolation and deselects
all INPUT terminals. This state is useful in a remote control system to isolate
the Product from the system analog bus. See Specifications. See the Remote
Programmer’s Manual.

 (Front Delay): Sets the delay before the front measurement is taken in a
scan operation. In Tru Ohms ratio, the front delay is implemented for
measurements in both the forward current and the reverse current. When the
Product is set as an input of front only, Tru Ohms also uses the front delay for the
forward and reverse currents. The delay can be set to Auto (default) or between
0 and 65 000 seconds.

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Features

The delay setting and resolution is shown in Table 16.

Table 16. Delay Settings and Resolution

Delay Setting Resolution

<1 s 1 ms

1 s to 10 s 10 ms

10 s to 65 000 s 100 ms

1. Use the cursor keys and to change from Front Delay: Auto to Front
Delay: [Value].

2. Use the cursor keys to select Front Delay.

3. Use the numerical keypad to change the value.

4. Push  to change and store the new value.

5. Push  to get back to the main input screen.

 (Rear Delay): Sets the delay before the rear measurement is taken in a
scan operation. In Tru Ohms ratio, the rear delay is implemented for
measurements in both the forward current and the reverse current. When the
Product is set as an input of rear only, Tru Ohms also uses the rear delay for the
forward and reverse currents. The delay can be set to Auto (default) or between
0 and 65 000 seconds. See Table 16 for delay setting and resolution.

1. Use the cursor keys and  to change from Rear Delay: Auto to Rear
Delay: [Value].

2. Use the cursor keys to select Front Delay.

3. Use the numerical keypad to change the value.

4. Push  to change and store the new value.

5. Push  to get back to the main input screen.

Use the Scan Operations

When the terminals are set to any one of the scan modes (Front - Rear, Front /
Rear, and (Front - Rear) / Rear), measurements are taken alternately from the
front and rear terminals. These measurements are combined mathematically to
produce a single result. Scan operations are available in these functions: DCV,
ACV, Ohms, Capacitance, and Thermocouple. They are not available in DCI,
ACI, digitize, RF Power, DCI Ext Shunt, ACI Ext Shunt, Frequency Counter, and
PRT.

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Scan Sequences

Note

In the Ohms function the scan operation switches both current
stimulus and potential difference measurement between the front
and rear terminals. This operation, also called Tru Ohms Ratio,
scans only the potential difference measurement between front and
rear terminals, maintaining the common stimulus current through
front and rear terminals. See 4W Tru Ohms Scan Mode (Tru Ohms

Ratio).

As the Product scans, each trigger event produces one scan result. The trigger
settings determine all the readings that make up a scan result. Scan runs through
this sequence for all scan operations except Tru Ohms Ratio, described below:

1. The Product waits with the rear terminals selected, and with the front
terminals isolated.

2. Upon receipt of a trigger, the Product executes any trigger delay.

3. After this delay, the Product changes to select the front terminals with the
rear terminals isolated.

4. The Product executes the front delay and takes a measurement.

5. The Product selects Rear Input with the front terminals isolated.

6. The Product executes the rear delay and takes a measurement

7. The displayed result is the combination of the two measurements.

The Product waits with Rear selected (front is isolated) for next trigger.

4W Tru Ohm Scan Mode (Tru Ohms Ratio)

When you select 4W Tru mode in Resistance (Ohms), the Scan modes above
(Front - Rear, Front / Rear, and (Front - Rear) / Rear) are configured uniquely in
a mode Fluke Calibration calls Tru Ohm Ratio, a feature also found in the Fluke
8508A Reference Multimeter. The Product applies a stimulus current of
alternating polarity through both resistors simultaneously, and the potential
difference measured across the resistors is scanned between the front and rear
terminals, see Figure 23. This measurement configuration is beneficial for lower
value resistance measurements between an unknown and a reference resistor,
and reduces self-heating (power) modulation that would otherwise result from
scanning the stimulus current between the two resistors under test. Tru Ohms
Ratio is only selectable if the ohms range is locked. If Auto range is selected, the
scan modes are greyed out and Tru Ohms Ratio is not available. See the screen
below.

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Reference Multimeter and 8 ½ Digit Multimeter

Features

INPUT HI

SENSE HI

Front Inpu t

Rear Input

SENSE LO

INPUT LO

Potential

Difference

Measur em ent

INPUT HI

SENSE HI

SENSE LO

INPUT LO

Figure 23. Tru Ohm Ratio Measurements

Stimulus Current
Source (Reversing)

adj132f.emf

iei036.png

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Operators Manual

The Scan sequence of measurement in Tru Ohms Ratio is:

1. The Product waits with Forward current applied to the two resistors, with the
rear SENSE terminals active.

2. Upon receipt of a trigger, the Product executes any trigger delay.

3. After this delay, the Product changes to sense at the front terminals.

4. The Product executes the front delay, and then a measurement is made with
the Forward current.

5. The Product switches to the Reverse current, executes the front delay, and
then takes another measurement.

6. The Product sets the rear SENSE terminals.

7. The Product executes the rear delay, and takes a measurement with the
Reverse current.

8. The Product switches to the forward current, executes the rear delay, and
then takes another measurement.

9. The displayed result is the combination of the four measurements made.

10. The Product waits with forward current and rear SENSE terminals activated
until the next trigger.

Auto range is not available in this mode.

To prevent possible electrical shock, fire, or personal injury, do
not connect external capacitance >50 nF to the Product
terminals.

HIGH VOLTAGE. To avoid equipment damage when using the
HV function make sure that circuits or components connected
to the Product can withstand at least 240 V dc.

External Guard

 (Ext. Guard) is part of the Inputs menu. Push  (Ext. Guard) to turn
the Guard to ON and OFF.

 (Ext. Guard) has these choices:

• OFF (default): The GUARD terminals on the front and rear panels are
isolated from each other and from any internal connection. The internal guard
shields connect directly to the internal 0 V.

• ON: The internal guard shields are disconnected from the internal 0 V, and
connected to the GUARD terminal of the selected front or rear input. See
Measure DC Volts.

XWWarning

WCaution

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Reference Multimeter and 8 ½ Digit Multimeter

Features

In the Ohms or PRT functions the external guard is modified to provide an Ohms
guard. In these cases the internal guard shields, and selected front or rear
GUARD terminal connects to the internal 0 V. See Figure 24 and Measure
Resistance.

Figure 24. Internal Guard Connections

adj062f.emf

Output Signal

 (Output Signal) controls the behavior of the rear BNC connector labeled
TRIG OUT. Push  (Output Signal) to open the Output Signal screen. Use
the cursor keys and  to choose from:

• OFF

• Signal Acquired

• Aperture open

• Reading counts complete

• On Event

• Reading complete

Use (Polarity) to change the polarity from POS to NEG.

When you select Aperture Open, the output is a square wave that is active while
the aperture is open. The TRIG OUT signal is an edge for all other selections.
Use the TRIG OUT signal.

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TRIG OUT

Many applications benefit from synchronizing the Product readings to other
external equipment. You can program the Product to output a TTL-compatible
signal on its Trigger Out (TRIG OUT) BNC connector when a specified reading
event occurs. The TRIG OUT signal is comparable to the HP/Agilent/Keysight
3458A EXTOUT signal. See Tables 17 and 18.

Push , and then  (Output Signal) to configure the TRIG OUT
reading event. See the screen below.

i004.png

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Reference Multimeter and 8 ½ Digit Multimeter

Features

Use the navigation keys and select the appropriate behavior for the TRIG OUT
signal. See Figure 25 for a detailed explanation.

Table 17. Output Behavior Choices

Trigger Out Reading Event Description Typical Usage

Signal Acquired

Aperture open

Reading counts complete

On Event (new)

Reading complete

1 μs output pulse occurs at the
end of the signal acquisition (a/d
integration period), before the
reading is actually complete.
Push  (Polarity) to select a
Pos (high) or Neg (low ) pulse.
See Figure 25.

Square wave output with a high
or low level during the signal
acquisition (integrate) period.
Push  (Polarity) to select a
Pos (high) or Neg (low) level.

1 μs output pulse occurs after a
specified number of readings is
completed. Push 
(Polarity) to select a Pos (high)
or Neg (low ) pulse.

The number of readings is
determined by the Count
parameter in Trigger Setup. See
Triggering Measurements.

1 μs output pulse occurs when a
Limit is exceeded. Limits are set
in the Analyze function.

1 μs output pulse occurs after
each reading for any
measurement function. For ACV
and ACI, which are sampled
measurements, a pulse is output
after each computed reading, not
after each sample in the
measurement process. Push
 (Polarity) to select a Pos
(high) or Neg (low ) pulse.

Trigger an external scanner
to the next channel. If the
scanner is a slower, relay
type, this setting advances
the channel sooner than the
Reading Complete event
below.

To minimize noise pickup
synchronizes external
equipment to only be active
when the Product A/D is not
acquiring a signal.

Synchronize an external
scanner to the Product when
making multiple readings
per scanner channel.

Advance an external
scanner to the next channel
when a voltage set by the
Limit Math function is
exceeded.

Synchronize an external
scanner to the Product when
making one reading per
scanner channel.

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Reading #1 Complete Reading #2 Complete Reading #3 Complete

A/D ConverterActivity:

SignalAcquired
TRIG OUT ACO, NEG

Aperture Open:
TRIG OUTAPE, NEG

Reading Counts Complete:
TRIG OUT BCOMP, NEG
(NRDGS 3)

On Event *
TRIG OUT O N, POS

Reading Complete
TRIG OUT RCO, POS

Reading Complete:
TRIG OUT RCO, NEG

A/D Busy:

Integrate

v

A/D Busy: v

Integrate

A/D Busy: v

Integrate

Figure 25. Timing Diagram for TRIG OUT Settings

iei104.emf

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Reference Multimeter and 8 ½ Digit Multimeter

Features

Table 18 shows the Product Trig Out remote commands compared to the
HP/Agilent/Keysight 3458A EXTOUT commands.

Table 18. Trig Out Remote Commands compared to the HP/Agilent/Keysight 3458A EXTOUT

Commands

8558A/8588A Trig Out 3458A EXTOUT

OFF OFF

Signal Acquired (ACO) ICOMP

Once ONCE

Aperture open (APE) APER

Multiple readings complete (BCO) BCOMP

On Event No equivalent

Reading complete (RCO) RCOMP

Not implemented SRQ

Zero

The Zero operation removes unwanted residual offsets in a given function and
range. These residual offsets are from either the Product, or from the connection
leads being used. Some specifications require the use of Zero or the Math Null
function under certain environmental conditions. See Specifications.

Zero is used when ambient temperature or input lead configurations change and
cause an offset from thermal emfs. Zero can also be used if you want the display
to read zero with a zero input and it does not due to small shifts within the
Product. (An exception is in ACV and ACI. See Use the Zero Operation.) Zero
works in all functions except PRT, RF Power, and Frequency Counter, or if a
Scan operation is selected.

Zero is retained after Instrument Reset ( > Reset Instrument), but
removed after power-off.

Math Null, accessed with , is a user-selected entry value that uses either
the numeric keypad or the  (Last Reading) softkey. Math Null is similar to
Zero, but it typically is used to offset readings based on other factors besides
thermal emfs or lead connections. For example, a calibrator source may have an
offset voltage of 10 mV, which can be entered as the "c" value in the Math
function. Subsequent measurements of the calibrator source will have the 10 mV
offset removed. Math Null is set to Off after an Instrument Reset ( >
Reset Instrument) or after power-off, and the null value is set to its default.

The Zero operation works up to 1 % of range, for example 100 mV on the 10 V
range. In 2 wire ohms, the limit is 1 % of range + 0.5 ohm; and in capacitance,
the limit is 1 % of range + 200 pF.

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Use the Zero Operation

 (Zero Range): initiates a series of measurements to zero the input and
save the result in volatile memory. Zero range only acts on the actual range the
Product is in, even if Auto range is selected. An indication of the application of an
input Zero is shown on the display, showing Zero On. Independent zero
corrections are provided for front and rear terminals and, when in ohms
functions, all of the modes and LoI On and Off operation. For ac always use the
lowest possible range. After the input Zero in ac, all subsequent readings will be
RSS’ed corrected by this zero so the reading may not absolutely show "zero".

 (Zero Function): initiates a series of measurements on each range in the
function starting with the highest range, to determine and correct for the residual
offset in each range.

 (Clear Range): Clears the Zero for the range the Product is currently on.
The Zero indicator is removed from the display.

 (Clear Function): Clears the Zero for the function the Product is currently
on. The Zero indicator is removed from the display.

 (Abort Zero): Aborts the Zero operation that is in progress. If a range or
function has a prior Zero value, that value is retained.

When performing the Zero operation, use the lead configuration for that particular
function, as it is typically thermal emfs from the lead connections that need to be
corrected. For DCV, ACV, and ohms, short the leads that are being used from HI
to LO. For DCI, ACI, and Capacitance, the leads HI to LO should be open. After
making the proper lead connections, observe the Product reading and wait for
the readings to become stable before you perform the Zero operation. The Zero
operation can also be used to have the Product read zero in DCV, ohms, or DCI
without the influence of external leads. To do so in DCV and ohms, short the
Product inputs with the shorting pcb accessory, and Zero functions or ranges as
appropriate. For DCI, leave the Product inputs open.

Ohms: An independent Zero can be executed for the modes (2W Normal, 4W
Normal, 4W Tru, 2W HV and 4W HV) as well as for LoI On or Off.

ACV and ACI: A Zero operation may not read exactly zero with the input leads
shorted as the displayed readings are root-sum-squared (RSS) with any noise
present.

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Reference Multimeter and 8 ½ Digit Multimeter

Features

Math

The Math menu provides selections for a variety of linear, averaging, and
logarithmic calculations. Push to access the Math menu, available in all
functions except Digitize and RF Power. See the screen below:

iei037.png

Math operations are performed on the readings obtained from the main
measurement function. With math enabled, the displayed reading is based on the
formula shown in Math Setup: (mx – c) / z. The “x” in the formula is either a
single reading from the Product, or an average reading based on the Average
value.

The three constants in the Math Setup formula are:

c: The displayed reading is the measurement minus the constant c. c is used to
offset or null a reading by entering a value using the numeric keypad or by
pushing  (Last Reading). Push  (ON) (or  (OFF)) to enable (or
disable) the use of this constant.

z: The displayed reading is the measurement divided by the constant z. It is used
to normalize a reading by entering a value using the numeric keypad or by
pushing  (Last Reading). Push  (ON) (or  (OFF)) to enable (or
disable) the use of this constant.

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m: The displayed reading is multiplied by a constant m. It is used to scale a
reading by entering a value using the numeric keypad. Push  (ON) (or
 (OFF)) to enable (or disable) the use of this constant. See the screen
below:

iei038.png

All constants and operations are independently selectable. The activation of any
math operation displays Math on the main display. An exponent is added to the
displayed reading if constants c, z, or m are enabled. All math operations remain
on when the function changes except when going into Digitize and RF Power. If
Math is enabled in DCV, for example, going into Digitize, turns Math off. Going
back to DCV turns Math back on.

Average can be set to either a Block average () or a Rolling average
(). The default is Rolling. The displayed reading is (mx– c) / z, where x is
the average of the readings as set by the Average value. With Average
highlighted in yellow, use the numeric keypad to enter the average value. When
set to Block average, the displayed reading is updated only after the number of
readings determined by Average are obtained, thus causing a slower reading
rate. In Rolling average, the displayed reading rate is not affected, although the
averaged value will not occur until after the number of readings specified in
Average are made. For example, with a rolling average set to 8, the 1st reading
will have no averaging, the 2nd readings is the average of readings 1 and 2, the
3rd reading is the average of 1, 2, and 3, and so on.

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Reference Multimeter and 8 ½ Digit Multimeter

Features

The displayed reading can also be altered by selecting a Unit parameter. The
Unit parameter affects how the reading is displayed after the Math Setup formula
is calculated. Measurement Units, for example “V”, will not be displayed when
Math Unit is set to ON.

Use the navigation keys to scroll down to Unit and push . The unit choices
and resultant display are

%: When set, the displayed reading is shown as a percentage of the reading (R)
at the time % was enabled. The displayed reading is given by

Display = ((Reading - R)/R * 100.

dB, Ref 1mW into 50 ohm: When set, the displayed reading is the power
delivered to a 50 ohm resistance referenced to 1mW based on a reading (R).
The displayed reading is given by

Display = 10 * log

(R2 /50)/1mW)

10

dB, Ref 1mW into 75 ohm: When set, the displayed reading is the power
delivered to a 75 ohm resistance referenced to 1mW based on a reading (R).
The displayed reading is given by

Display = 10 * log

(R2 /75)/1mW)

10

dB, Ref 1mW into 600 ohm: When set, the displayed reading is the power
delivered to a 600 ohm resistance referenced to 1mW based on a reading (R).
The displayed reading is given by

Display = 10 * log

(R2 /600)/1mW)

10

dB, Ref unity: When set, the displayed reading is a ratio in decibels relative to 1.
The displayed reading is given by

Display = 20 * log

10

(R)

Note

The Unit choices of dB, Ref 1mw are available only in DCV and
ACV.

Note

To reset all Math constants and settings to their default values, push
 and  (Reset Instrument).

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Analyze

Analyze provides different views of measurements. To access the Analyze
features, push . To use the full capabilities of the Analyze function, a
discussion of measurement records used in the Product is warranted. All
measurements are stored in a volatile buffer called a record. When the Product is
powered up, the Trigger subsystem default is the free-run mode and readings are
captured continuously into a record. The maximum number of readings in a
record is limited by the size of the reading buffer and the number of elements in
each result as shown in Table 19.

Table 19. Analyze Record

Result Elements Time Stamp Off Time Stamp On

Primary value only 15000000 7500000

Primary + secondary value 7500000 5000000

Scan primary values only 5000000 3750000

Scan primary + secondary
values

3750000 3000000

If the reading buffer reaches the maximum size, the Product continues to read
and display the numerical readings but the readings are not stored or plotted.
The statistic calculation also stops.

No readings are placed into a record when the Trigger subsystem is in its Idle
state, accomplished by pushing  or by putting the Product into
Continuous OFF using . See Triggering Measurements. When the
Trigger subsystem comes out of the Idle state, the previous record is discarded
and a new record is initiated. A new record also starts when the Product’s main
function is changed, and when certain parameters within a function are changed,
like its range or resolution. Unless a record is copied to another memory location
in Memory Setup, it is lost once a new record is started.

These softkeys are available when you push :

 (Statistics)

 (Chart + Statistics)

 (Chart Only)

 (Limits)

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Reference Multimeter and 8 ½ Digit Multimeter

Features

These features are available in all of the functions: DCV, ACV, DCI, ACI, Ohms,
Capacitance, RF Power, Frequency, DCI Ext Shunt, ACI Ext Shunt, PRT, and
Thermocouple. It is also available in Digitize but Statistics is not available, and
Histogram is replaced with Frequency. See Using Analyze in Digitize Mode.

 (Statistics): When pushed, the Statistics feature is displayed, showing the
Maximum, Minimum, Span (Max – Min), Average, Standard Deviation, and total
number of readings in the data record. Statistics does not start a new record
when first enabled, using data in the current record. A new record is started upon
power-up, a Product reset, and whenever there is a function change, or a change
of parameters in a function. For example, range, resolution and input
characteristics; or when the Trigger subsystem is taken out of the Idle mode. A
convenient way to start a new record (in all functions except Digitize) is to push

. This puts the Product triggering in the Idle mode, then you can push
 once again to put the Product into the free-run triggering mode.

In Statistics,  (Std Dev) determines how the standard deviation displays,
either in the units of the measurement, or in parts per million (PPM). See the
screen below.

iei039.png

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Statistics Example

Measurement: Quantify the performance of a number of dc outputs, making 10
measurements each time to evaluate the average and noise of the output.

Solution: In Trigger Setup, set the Triggers/Arm (Count) to 10. In DCV, push
to enable Statistics and then (Statistics). Push  to put the
Product into the Idle triggering mode. Each push of  gives new 10 readings
and stops. The average of 10 readings is displayed, and the standard deviation is
representative of the noise in the output signal.

 (Chart + Statistics): When pushed, Statistics display along with either a
plot of the Trend or Histogram. Trend provides a visual trending of
measurements over time, where the vertical axis is the amplitude of the signal
and the horizontal axis is time. Histogram provides a graphical representation of
the distribution of a series of measurements. Measurements are grouped in bins
as shown with vertical bars. The vertical axis indicates the relative number of
readings for a range of values as a percentage. The sum of the vertical bars
equals 100 %. In Chart + Statistic view, about one-third of the Product’s display is
used for the chart.

 (Chart + Statistics) menu is comprised of:

 (Std Dev) where Normal displays the standard deviation of the data

record in the measurement units, and PPM displays it as parts per million.

 (Plot) selects either the Trend or Histogram plots.

If Trend is selected,

 (Mode) selects which part of the data record is displayed. All shows the
measurement points from the beginning of the record. The left side of the
horizontal axis in this case starts from 0. Recent shows the most recent readings
at the time of the button push, where the left side of the horizontal axis is the total
number of readings minus 101, effectively showing the last 100 readings at the
time of the button push. The right side shows the total number of measurements
or the time scale of the record in both cases. See the screens below.

Under Trend Setup:

 (Auto) gives automatic scaling of the vertical axis such that all data in the
record is displayed with optimum vertical scale.

 (Manual) allows user control of the vertical scale (maximum and
minimum).

 (Auto Once) sets the vertical scale appropriately for the data record
captured so far but does not continue to rescale the chart as more data is added
(as Auto would do).

 (X-axis) allows selection of the horizontal axis, as either the number of
readings, or time. To use Time, first enable Timestamps in the Memory Setup
menu.

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Reference Multimeter and 8 ½ Digit Multimeter

Features

iei040.png

iei041.png

If  (Plot) is selected to Histogram,

 (Bin Settings) provides control of the horizontal axis, using either Auto or
Manual. As long as new readings are being made, changing between Auto and
Manual gives different views of the reading distribution. If the data collection is
stopped by a push of , only the present view of the data shows. For
example, if Bin Settings is set to Manual, after you push , only the
Manual bin view shows.

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 (Auto): The horizontal axis shows the number of bins based on the
number of measurements in the data record and the noise level of the input.
Typically, the number of bins increases with more measurements, where 100
measurements may give 7 bins, while 1000 measurements may give 11 bins.
Auto implicitly assumes a normal distribution.

 (Manual): For a different view of the measurement value, choose the
 (Manual) setting. The Manual menu # Bins sets the horizontal axis, up to

100 bins. The bin horizontal axis can be specified as either Low and High values,
or as a Span around a Center value.

Histogram using similar data records, with Auto or Manual horizontal scale
settings are shown below:

iei042.png

iei043.png

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Reference Multimeter and 8 ½ Digit Multimeter

Features

Note

When you use Chart, use a fixed range as Auto range can affect the
data. If there are any measurements in the record that are
overrange, the chart does not include that data point, and the chart
turns red.

The other softkeys in Analyze are

 (Chart Only): Shows a Chart (either Trend or Histogram) without showing
the Statistics data. Behavior and control of the Chart is the same as in 
(Chart + Statistics). In Chart Only, the chart uses the entire display.

 (Limits): Provides a visual indicator of the input relative to settable higher
and lower limits. When either the upper or lower limit is exceeded, the respective
up/down arrow turns red as shown in the screen below:

iei044.png

 (Limits Setup): Set the upper and lower limit using  and the
numeric keypad. The Upper and Lower limit can be individually turned On or Off.

 (Limits): Turns the Limits display ON or OFF.

 (Clear Alarm): If a limit shows a red indication, pushing this softkey turns

it back to green until another reading causes that limit to be exceeded.

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Using Analyze in Digitize Mode

In Digitize, Analyze always uses the full record of the digitized data. Charting
takes place after the data is captured, not live as in the other functions. Analyze
in Digitize does not have Statistics as it does in the other functions. It has two
ways to chart the data:

Trend chart: The Trend chart is similar to the one in all of the other functions.

 (Auto) or  (Manual) scales the vertical axis, and an  (Auto
Once) feature which scales the data to fit the chart one time, then reverts to

Manual.

Frequency domain histogram chart: The captured data is processed by a
Discrete Fourier Transform to convert the digitized time domain data to the
frequency domain. The Frequency domain chart provides a convenient way to
view the spectral content of the data without external post processing.

When Analyze is enabled, pushing  acquires and plots another data set.
See the screens below.

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iei046.png

Reference Multimeter and 8 ½ Digit Multimeter

Memory Setup

Memory Setup

Push  to access memory management menus. See Table 20. The
display shows the Instrument Setup information.

• # Readings: Shows the number of readings in the record, and continuously
updates if the Product is in the free-run trigger state.

• Unused volatile memory: Shows the number of bytes remaining in volatile
memory. A reading by itself takes 9 bytes. Other data, for example, multiple
measurements and time stamps, can use 5 times more than that.

• Stored records: Shows the number of records stored.

• Unused non-volatile memory: Shows the number of bytes available in non-

volatile memory. Using this memory allows a greater record size, at the
expense of some speed degradation in internal data transfers and effective
reading rate.

• Store readings to: Determines where readings are stored. The default is the
volatile buffer. This parameter is set by  (Store Results To).

Submenus from Memory Setup are accessed with each softkey. See Table 20.

Table 20. Memory Management Menu

Menu Softkeys Parameter


(Time Stamp)



(Store results to)

Add time stamps on stored records. The choice is OFF or ON.

Choose where to store the results data. Choices are:

• Volatile Buffer Only. This is the default and provides the fastest data
transfer into memory and thus, the fastest effective reading rate. The
volatile buffer can hold 15 000 000 readings with Time Stamp Off, 7
500 000 with Time Stamp On. When the buffer reaches its storage limit,
any new readings are discarded.

• Non-volatile memory. This stores results in the on-board non-volatile
memory.

Use the navigation keys to move the cursor to highlight the storage method and
then push  to make the choice. Push  to return to the Memory
Setup menu.

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
(Save Record)



(Manage Records)

Table 20. Memory Management Menu (cont.)

Menu Softkeys Parameter

Push to select the current record into an archived record. Each push of this
softkey makes another archived record, as shown by the Stored Records field.
If the current record is still accumulating readings (in other words, the Product
is in the free-run mode), it continues to do so even after you push  (Save
Record). Push  (Manage Records) to view archived records.

Push to enter the Manage Records menu. The Manage Records menu shows
the archived records, which are stored as CSV files. See Figure 26. The
Records column shows the record file name and uses the date and time. The
latest record is shown on top. The # Readings column shows the number of
readings in each record. The Comment column contains user entered
comments using  (Edit Comment) softkey. Comments are not stored in
the archived record, but only shows up in the Manage Records menu to help
identify records. The comment field is 15 characters wide. The Manage
Records softkeys are:

 (Page Down): Used to view the archived records.

 (Page Up): Used to view the archived records.

 (Copy): Gives a submenu to copy a record into USB memory, with

these softkeys:

 (Copy to USB): Copies the highlighted record into USB memory.

 (Copy All to USB): Copies all of the archived records into USB

memory. The Product does not uniquely identify the USB ports. Insert only one
USB memory device during this operation. Push  to move back to exit
this submenu.

 (Edit Comment): Comments can be entered with the pop-up letter
keypad and , or the Product numeric keypad and .  in the
numeric keypad is used for both numeric and letter entry.

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Figure 26. Manage Records Menu

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