Used Agilent Agilent Used 34450A Manual

Test Equipment Depot - 800.517.8431 - 99 Washington Street Melrose, MA 02176 - TestEquipmentDepot.com

Keysight 34405A 5 ½ Digit
Multimeter

User’s and
Service Guide

Notices

CAUTION

WARNING

© Keysight Technologies 2006 - 2014

No p art o f this manu al may be re produce d in
any form or by any means (including elec­tronic storage and retrieval or translation
into a foreign language) without prior agree­ment and written consent from Keysight
Technologies as governed by United States
and international copyright laws.

Manual Part Number

34405-91000

Edition

Edition 13, August 2014

Printed in Malaysia
Keysight Technologies

1400 Fountaingrove Parkway
Santa Rosa, CA 95403

Software Revision

This guide is valid for the firmware that was
installed in the instrument at the time of
manufacture. However, upgrading the firm­ware may add or change product features.
For the latest firmware and documentation,
go to the product page at:

Warranty

The material contained in this docu­ment is provided “as is,” and is sub­ject to being changed, without notice,
in future editions. Further, to the max­imum extent permitted by applicable
law, Keysight disclaims all warran­ties, either express or implied, with
regard to this manual and any infor­mation contained herein, including
but not limited to the implied warran­ties of merchantability and fitness for
a particular purpose. Keysight shall
not be liable for errors or for inciden­tal or consequential damages in con­nection with the furnishing, use, or
performance of this document or of
any information contained herein.
Should Keysight and the user have a
separate written agreement with
warranty terms covering the material
in this document that conflict with
these terms, the warranty terms in the
separate agreement shall control.

Technology Licenses

The hardware and/or software described in
this document are furnished under a license
and may be used or copied only in accor­dance with the terms of such license.

Restricted Rights Legend

U.S. Government Restricted Rights. Soft­ware and technical data rights granted to
the federal government include only those
rights customarily provided to end user cus­tomers. Keysight provides this customary
commercial license in Software and techni­cal data pursuant to FAR 12.211 (Technical
Data) and 12.212 (Computer Software) and,
for the Department of Defense, DFARS

252.227-7015 (Technical Data - Commercial
Items) and DFARS 227.7202-3 (Rights in
Commercial Computer Software or Com­puter Software Documentation).

Safety Notices

A CAUTION notice denotes a haz­ard. It calls attention to an operat­ing procedure, practice, or the like
that, if not correctly performed or
adhered to, could result in damage
to the product or loss of important
data. Do not proceed beyond a
CAUTION notice until the indicated
conditions are fully understood and
met.

A WARNING notice denotes a
hazard. It calls attention to an
operating procedure, practice, or
the like that, if not correctly per­formed or adhered to, could result
in personal injury or death. Do not
proceed beyond a WARNING
notice until the indicated condi­tions are fully understood and
met.

II 34405A User’s and Service Guide

Safety Information

WARNING

WARNING

WARNING

WARNING

Do not defeat power cord safety ground fea­ture. Plug in to a grounded (earthed) outlet.

Do not use product in any manner not speci­fied by the manufacturer.

Do not install substitute parts or perform
any unauthorized modification to the prod­uct. Return the product to a Keysight Tech­nologies Sales and Service Office for service
and repair to ensure that safety features are
maintained.

Safety Symbols

Earth Ground

Main Power and Test Input Dis­connect: Unplug instrument from
wall outlet, remove power cord,
and remove all probes from all
terminals before servicing. Only
qualified, service-trained person­nel should remove the cover from
the instrument.

Protection Limits: To avoid instru­ment damage and the risk of elec­tric shock, do not exceed any of
the Protection Limits defined in
the following section.

Chassis Ground

CAT II (300V) IEC Measurement Category II.

Risk of electric shock

Refer to manual for addi­tional safety information

Inputs may be connected to
mains (up to 300 VAC) under
Category II overvoltage condi­tions.

Line and Current Protection
Fuses: For continued protection
against fire, replace the line fuse
and the current-protection fuse
only with fuses of the specified
type and rating.

IEC Measurement Category II. The
HI and LO input terminals may be
connected to mains in IEC Cate­gory II installations for line volt­ages up to 300 VAC. To avoid the
danger of electric shock, do not
connect the inputs to mains for
line voltages above 300 VAC. See
"IEC Measurement Category II
Overvoltage Protection" on the
following page for further infor­mation.

34405A User’s and Service Guide III

12A
rms

1000VDC

500Vpk

1.2A
rms

1.25A/500V FH

LO

CAT II (300V)

750VAC

HI

I

V

12A

Fused

A

C

D

B

Protection Limits

The Keysight 34405A Digital Multimeter
provides protection circuitry to prevent
damage to the instrument and to protect
against the danger of electric shock, pro­vided that the Protection Limits are not
exceeded. To ensure safe operation of the
instrument, do not exceed the Protection
Limits shown on the front panel, as defined
below:

Note: The front-panel terminals and current
protection fuse are shown above.

Input Terminal Protection
Limits

Protection Limits are defined for the input
terminals:

Main Input (HI and LO) Terminals. The HI
and LO input terminals are used for voltage,
resistance, capacitance, and diode test
measurements. Two Protection Limits are
defined for these terminals:

HI to LO Protection Limit. The Protection
Limit from HI to LO ("A" in the figure at
left) is 1000 VDC or 750 VAC, which is
also the maximum voltage measurement.
This limit can also be expressed as 1000
Vpk maximum.

IV 34405A User’s and Service Guide

LO to Ground Protection Limit. The LO

input terminal can safely "float" a maxi­mum of 500 Vpk relative to ground. This is
Protection Limit "B" in the figure.

Although not shown on the figure, the Pro­tection Limit for the HI terminal is a maxi­mum of 1000 Vpk relative to the ground.
Therefore, the sum of the “float” voltage
and the measured voltage must not exceed
1000 Vpk

Current Input Terminal. The current input
("I") terminal has a Protection Limit of 1.2A
(rms) maximum current flowing from the LO
input terminal. This is Protection Limit "C"
in the figure. Note that the current input ter­minal will be at approximately the same
voltage as the LO terminal.

Note: The current-protection circuitry
includes a fuse on the front panel. To main­tain protection, replace this fuse only with a
fuse of the specified type and rating.

12A Current Input Terminal. The 12A cur­rent input terminal has a Protection Limit of
12A (rms) maximum current flowing from
the LO input terminal. This is Protection
Limit "D" in the figure. Note that the current
input terminal will be at approximately the
same voltage as the LO terminal.

Note: The current-protection circuitry
includes an internal fuse. To maintain pro­tection, service-trained personnel should
replace this fuse only with a fuse of the
specified type and rating.

IEC Measurement Category II
Overvoltage Protection

To protect against the danger of electric
shock, the Keysight 34405A Digital Multim­eter provides overvoltage protection for
line-voltage mains connections meeting
both of the following conditions:

The HI and LO input terminals are con­nected to the mains under Measurement
Category II conditions, defined below, and

The mains are limited to a maximum line
voltage of 300 VAC.

IEC Measurement Category II includes elec­trical devices connected to mains at an out­let on a branch circuit. Such devices include
most small appliances, test equipment, and
other devices that plug into a branch outlet
or socket. The 34405A may be used to make
measurements with the HI and LO inputs
connected to mains in such devices, or to
the branch outlet itself (up to 300 VAC).
However, the 34405A may not be used with
its HI and LO inputs connected to mains in
permanently installed electrical devices
such as the main circuit-breaker panel,
sub-panel disconnect boxes, or permanently
wired motors. Such devices and circuits are
subject to overvoltages that may exceed the
protection limits of the 34405A.

Note: Voltages above 300 VAC may be mea­sured only in circuits that are isolated from
mains. However, transient overvoltages are
also present on circuits that are isolated
from mains. The Keysight 34405A is
designed to safely withstand occasional
transient overvoltages up to 2500 Vpk. Do
not use this equipment to measure circuits
where transient overvoltages could exceed
this level.

Additional Notices

WARNING

This product complies with the WEEE Direc­tive (2002/96/EC) marking requirement.
The affixed product label (see below) indi­cates that you must not discard this electri­cal/electronic product in domestic
household waste.

Product Category: With reference to the
equipment types in the WEEE directive
Annex 1, this product is classified as a
"Monitoring and Control instrumentation"
product.

Do not dispose in domestic household
waste.

The Keysight 34405A is provided
sight 34138A Test Lead Set, described
below.

st Lead Ratings

Te

Test Leads - 1000V, 15A

Fine Tip Probe Attachments - 300V, 3A

Mini Grabber Attachment - 300V, 3A

SMT Grabber Attachments - 300V, 3A

tion

Opera

ith a Key-

w

The Fine Tip, Mini Grabber, and SMT Grab­ber attachments plug onto the probe end of
the Test Leads.

Maintenance

If any portion of the Test Lead Set is worn or
damaged, do not use. Replace with a new
Keysight 34138A Test Lead Set.

If the Test Lead Set is used in a
manner not specified by Keysight
Technologies, the protection pro­vided by the Test Lead Set may be
impaired. Also, do not use a dam­aged or worn Test Lead Set.
Instrument damage or personal
injury may result.

34405A User’s and Service Guide V

Declaration of Conformity (DoC)

NOTE

The Declaration of Conformity (DoC) for this instrument is available on the Web site. You can
search the DoC by its product model or description.

http://regulations.products.keysight.com/DoC/search.htm

If you are unable to search for the respective DoC, please contact your local Keysight
representative.

VI 34405A User’s and Service Guide

Contents

1 Getting Started Tutorial 11

Introducing the Keysight 34405A Multimeter 12

Checking the Shipping Contents 13

Connecting Power to the Multimeter 13
Adjusting the Handle 14
The Front Panel at a Glance 15

The Display at a Glance 16
The Rear Panel at a Glance 17
Remote Operation 18

Configuring and Connecting the USB Interface 18

SCPI Commands 18
Making Measurements 20

Measuring AC or DC Voltage 20

Measuring Resistance 21

Measuring AC (RMS) or DC Current up to 1.2A 21

Measuring AC (RMS) or DC Current up to 12A 22

Measuring Frequency 22

Testing Continuity 23

Checking Diodes 23

Measuring Capacitance 24

Measuring Temperature 24
Selecting a Range 25
Setting the Resolution 26

2 Features and Functions 27

Math Operations 28

Null 29

dBm 29

dB 30

Min/Max 30

Limit 31

Hold 31

34405A User’s and Service Guide VII

Contents

Math Annunciators 32
Using the Secondary Display 33

Measurement Functions and the Secondary Display 33

Math Operations and the Secondary Display 35

Using the Utility Menu 36

Changing Configurable Settings 37

Reading Error Messages 38

The Beeper 39
Editing Values in the Secondary Display 40

Selecting the Value to Edit 40

Editing Values 40
Storing and Recalling Instrument States 41

Storing a State 41

Recalling a Stored State 42
Reset/Power-On State 43
Triggering the Multimeter 45

3 Measurement Tutorial 47

DC Measurement Considerations 48
Noise Rejection 49
Resistance Measurement Considerations 51

AC Measurements 52
True RMS AC Measurements 53
Other Primary Measurement Functions 56

Frequency Measurement Errors 56

DC Current Measurements 56

Capacitance Measurements 57

Temperature Measurements 58
Other Sources of Measurement Error 59

4 Performance Tests and Calibration 63

Calibration Overview 64

Closed - Case Electronic Calibration 64

Keysight Technologies Calibration Services 64

Calibration Interval 64

Time Required for Calibration 65
Recommended Test Equipment 66

VIII 34405A User’s and Service Guide

Test Considerations 67

Input Connections 67
Performance Verification Tests Overview 68

Self -Test 68

Quick Performance Check 69
Performance Verification Tests 70

Zero Offset Verification 71

Gain Verification 73

Optional AC Voltage Performance Verification Test 79

Optional AC Current Performance Verification Test 80

Optional Capacitance Performance Verification Test 81
Calibration Security 82

Unsecuring the Instrument for Calibration 83
Calibration Process 85

Using the Front Panel for Adjustments 86
Adjustments 88

Zero Adjustment 88

Gain Adjustments 89

DC Voltage Gain Adjustment Procedure 91

DC Current Gain Adjustment Procedure 92

AC Voltage Gain Adjustment Procedure 94

AC Current Gain Adjustment Procedure 95

Ohms Gain Adjustment Procedure 97

Frequency Gain Adjustment Procedure 98

Capacitance Gain Adjustment Procedure 99

Finishing the Adjustments 101

Calibration Message 102

To Read the Calibration Count 102
Calibration Errors 103

Contents

5 Disassembly and Repair 105

Operating Checklist 106

Types of Service Available 107

Repackaging for Shipment 108

Cleaning 108

To Replace the Power Line Fuse 109

To Replace a Current Input Fuse 110

Electrostatic Discharge (ESD) Precautions 112

34405A User’s and Service Guide IX

Contents

Mechanical Disassembly 113

Replaceable Parts 120

Rack Mounting 121

6 Specifications 123

[1]

DC Specifications
AC Specifications

125

[1]

126
Temperature and Capacitance Specifications
Operating Specifications 128
Supplemental Measurement Specifications 129
General Characteristics 133

To Calculate Total Measurement Error 135
Accuracy Specifications 136

Configuring for Highest Accuracy Measurements 137

Index 141

[1]

127

X 34405A User’s and Service Guide

34405A 5 ½ Digit Multimeter
User’s and Service Guide

1 Getting Started Tutorial

Introducing the Keysight 34405A Multimeter 12
Checking the Shipping Contents 13
Connecting Power to the Multimeter 13
Adjusting the Handle 14
The Front Panel at a Glance 15
The Rear Panel at a Glance 17
Measuring AC or DC Voltage 20
Measuring Resistance 21
Measuring AC (RMS) or DC Current up to 1.2A 21
Measuring AC (RMS) or DC Current up to 12A 22
Measuring Frequency 22
Testing Continuity 23
Checking Diodes 23
Measuring Capacitance 24
Measuring Temperature 24
Selecting a Range 25
Setting the Resolution 26

This chapter contains a quick tutorial showing how to use
the front panel to make measurements.

1 Getting Started Tutorial

Introducing the Keysight 34405A Multimeter

The multimeter’s key features are:

• 5 ½- digit dual display measurements

• Ten measurement functions:

• AC voltage

• DC voltage

• Two- wire resistance

• AC current

• DC current

• Frequency

• Continuity

• Diode Test

• Temperature

• Capacitance

• Six math functions:

• Null

• dBm

• dB

• Min/Max

• Limit

• Hold

• 4 ½- or 5 ½- digit measurements

• Dual display

• USB 2.0, USBTMC- USB488 device class

12 34405A User’s and Service Guide

Getting Started Tutorial 1

NOTE

Checking the Shipping Contents

Verify that you have received the following items with your multimeter:

• One test lead kit

• One power cord

• One USB interface cable

• A Quick Start Guide

• A Certificate of Calibration (test report included)

• A CD- ROM containing the remote programming online help, online

manuals, application software, and instrument drivers

• A Keysight IO Library CD- ROM

If anything is missing, contact your nearest Keysight Sales Office.

Connecting Power to the Multimeter

Connect the power cord and press the Power switch to turn on the
multimeter.

The front- panel display illuminates while the multimeter performs its
power- on self- test. (If the multimeter does not power- on, refer “Operating

Checklist” on page 106).

The multimeter powers up in the DC voltage function with autoranging
enabled. If self- test is successful, the multimeter goes to normal operation.
If the self- test is not successful, Error is displayed on the left side of the
display and an error number is displayed in the upper right side of the
display. In the unlikely event that self- test repeatedly fails, contact your
nearest Keysight Sales Office.

A more extensive self-test is available from the Utility menu see “Using the Utility Menu”

on page 36 for details.

34405A User’s and Service Guide 13

1 Getting Started Tutorial

Benchtop Positions

Carrying Position

Adjusting the Handle

To adjust the handle, grasp the handle by the sides and pull outward.
Then, rotate the handle to the desired position.

14 34405A User’s and Service Guide

The Front Panel at a Glance

12A
rms

1000VDC

500Vpk

1.2A
rms

1.25A/500V FH

LO

CAT II (300V)

750VAC

HI

I

Power

Local

Auto

Hold Utility

dBmdB

Digits

Range

Cont

NullFreq

Temp

Store

Recall

Disp

Shift

V

)))

Agilent



34405A
5 Digit Multi meter

mV DC

45

ACI

DCI

DCV ACV

Store

Recall

MnMx

Temp Limit

Null

Freq

½

12A

Fused

1

2 3 5 6 7 8 94

Edit

Enter

mV DC

Range

1 Display
2 On/Off Switch
3 Measurement Function and Resolution Keys
4 Autorange and Manual Range
5 Math Operations and Edit

6 State Store/Recall, Utility and Edit Keys
7 Shift (selects blue shifted keys) and

Local key

8 Secondary Display Key
9 Input Terminals and Current Fuse

Getting Started Tutorial 1

34405A User’s and Service Guide 15

1 Getting Started Tutorial

1 Primary Measurements and CAL Annunciator
2 Primary Measurement Function and Units
3 Math and State Storage Annunciators
4 Range and Shift Annunciators

5 System Annunciators
6 Secondary Display
7 Secondary Measurement

Function and Units

mVA DC AC

Mk Hz μnF

°C °F dBm

Remote ManRng H old Limit Null MnMx

mVA DC AC

Mk Hz μnF

°C °F dBm

MaxMinAvgN Ref R Value

Store Recall HiLo Limit

Range

CAL

Shift

5 6 7

1 2 3 4

The Display at a Glance

The System Annunciators (above the primary display) are described below
(see page 32 for Math Annunciators and Chapter 4 for the calibration
annunciator).

System Annunciator Description

Sample annunciator--indicates readings being taken.

*

Remote The multimeter is operating in the remote interface mode.

ManRng Fixed range selected (autoranging disabled).

Hold Reading hold function enabled.

Limit Limit math feature enabled

Null Null math feature enabled.

MnMx Min/Max feature enabled.

Shift Shift key has been pressed.

16 34405A User’s and Service Guide

Diode test function selected.

Continuity test function selected.

The Rear Panel at a Glance

4 AC Power Connector
5 AC Line Voltage Selector
6 AC Line Fuse

1 USB Interface Connector
2 Model and Serial Number Label
3 Chassis Ground Lug

1

3

4

2

5

6

Getting Started Tutorial 1

34405A User’s and Service Guide 17

1 Getting Started Tutorial

Local

Shift

NOTE

NOTE

Remote Operation

The instrument automatically enters the Remote state whenever SCPI

commands are received over the USB bus interface. When in the Remote

state, pressing returns the multimeter to front panel operation.

Configuring and Connecting the USB Interface

There is nothing to configure on your instrument for a USB connection.
Just connect the instrument to your PC using the USB 2.0 cable included
with the instrument.

To easily configure and verify an interface connection between the 34405A and your PC,
use the Automation–Ready CD, which is shipped with your 34405A. This CD includes the
Keysight IO Libraries Suite and the Keysight Connection Expert application.

SCPI Commands

The Keysight 34405A complies with the syntax rules and conventions of
SCPI (Standard Commands for Programmable Instruments).

For a complete discussion of 34405A SCPI syntax, refer to the Keysight 34405A
Programmer’s Reference Help, This help is provided on the Keysight 34405A Product
Reference CD-ROM that came with your instrument.

18 34405A User’s and Service Guide

Getting Started Tutorial 1

SCPI Language Version

You can determine the multimeter’s SCPI language version by sending the
SYSTem:VERSion? command from the remote interface.

• You can query the SCPI version from the remote interface only.

• The SCPI version is returned in the form “YYYY.V”, where “YYYY”

represents the year of the version, and “V” represents a version number
for that year (for example, 1994.0).

34405A User’s and Service Guide 19

1 Getting Started Tutorial

ACV

DCV

12A
rms

1000VDC

500Vpk

1.2A
rms

1.25A/500V FH

LO

CAT II (300V)

750VAC

HI

I

V

12A

Fused

AC or DC Voltage Source

mV DC

mV DC

Range

Typical DCV Display:

mV

mV AC

Range

AC

Typical ACV Display:

+

-

Making Measurements

The following pages show how to make measurement connections and how
to select measurement functions from the front panel for each of the
measurement functions.

For remote operation, refer to the MEASure Subsystem in the Keysight
34405A Online Programmer’s Reference online help.

Measuring AC or DC Voltage

AC Voltage:

• Five Ranges: 100.000 mV, 1.00000 V, 10.0000 V, 100.000 V, 750.00 V

• Measurement Method: AC coupled true rms - measures the AC component with up to 400 VDC

bias on any range.

• Crest Factor: Maximum 5:1 at full scale

• Input Impedance: 1 MΩ ± 2% in parallel with <100pF on all ranges

• Input Protection: 750V rms on all ranges (HI terminal)

20 34405A User’s and Service Guide

DC Voltage:

• Five Ranges: 100.000 mV, 1.00000 V, 10.0000 V, 100.000 V, 1000.00 V

• Measurement Method: Sigma Delta A-to-D converter

• Input Impedance: ~10 MΩ all ranges (typical)

• Input Protection: 1000V on all ranges

(HI terminal)

Getting Started Tutorial 1

Typical Display:

12A
rms

1000VDC

500Vpk

1.2A
rms

1.25A/500V FH

LO

CAT II (300V)

750VAC

HI

I

V

12A

Fused

Resistance

Test

Current

Range

ACI

DCI

Typical ACI Display:

12A
rms

1000VDC

500Vpk

1.2A
rms

1.25A/500V FH

LO

CAT II (300V)

750VAC

HI

I

V

12A

Fused

+

AC or DC Current Source

-

m A DC

m A DC

Range

m A AC

m A AC

Range

Typical DCI Display:

Measuring Resistance

• Seven Ranges: 100.000Ω, 1.00000 kΩ, 10.0000 kΩ, 100.000 kΩ, 1.00000 MΩ, 10.0000 MΩ, 100.000

MΩ

• Measurement Method: two-wire ohms

• Open-circuit voltage limited to < 5 V

• Input protection 1000 V on all ranges (HI terminal)

34405A User’s and Service Guide 21

Measuring AC (RMS) or DC Current up to 1.2A

• Three AC Current or DC Current Ranges: 10.0000 mA, 100.000 mA, 1.00000 A

• Shunt Resistance: 0.1Ω to 10 Ω for 10mA to 1A ranges

• Input Protection: Front Panel 1.25A, 500V FH fuse for I terminal

1 Getting Started Tutorial

DCI

ACI

Typical ACI Display:

12A
rms

1000VDC

500Vpk

1.2A
rms

1.25A/500V FH

LO

CAT II (300V)

750VAC

HI

I

V

12A

Fused

+

AC or DC Current Source

-

A DC

A DC

Range

A AC

A AC

Range

Typical DCI Display:

Freq

Freq

Typical Display:

12A
rms

1000VDC

500Vpk

1.2A
rms

1.25A/500V FH

LO

CAT II (300V)

750VAC

HI

I

V

12A

Fused

Frequency

Source

Hz

Range

VAC

Measuring AC (RMS) or DC Current up to 12A

• 10 Amp AC Current or DC Current Range

• Shunt Resistance: 0.01 Ω for 10A range

• Internal 15A, 600V fuse for 12A terminal

Measuring Frequency

• Five Ranges: 100.000 mV, 1.00000 V, 10.0000 V, 100.000 V, 750.00 V. Range is based on the voltage

level of the signal, not frequency.

• Measurement Method: Reciprocal counting technique.

• Signal level: 10% of range to full scale input on all ranges

• Gate Time: 0.1 second or 1 period of the input signal, whichever is longer.

• Input Protection: 750V rms on all ranges (HI terminal)

22 34405A User’s and Service Guide

Getting Started Tutorial 1

Shift

Cont )

)

)

Open Circuit Display:

12A
rms

1000VDC

500Vpk

1.2A
rms

1.25A/500V FH

LO

CAT II (300V)

750VAC

HI

I

V

12A

Fused

Open or

Closed
Circuit

Test

Current

Typical Closed Circuit Display:

Shift

Freq

Freq

Reverse Bias or Open Diode Display:

12A
rms

1000VDC

500Vpk

1.2A
rms

1.25A/500V FH

LO

CAT II (300V)

750VAC

HI

I

V

12A

Fused

Forward Bias

Test

Current

VDC

Typical Forward Biased Diode Display:

Testing Continuity

• Measurement Method: 0.83 mA ± 0.2% constant current source, < 5 V open circuit voltage.

• Response Time: 70 samples/ second with audible tone

• Continuity Threshold: 10 Ω fixed

• Input Protection: 1000 V (HI terminal)

34405A User’s and Service Guide 23

Checking Diodes

• Measurement Method: Uses 0.83 mA ± 0.2% constant current source, < 5 V open circuit voltage.

• Response Time: 70 samples/ second with audible tone

• Input Protection: 1000 V (HI terminal)

1 Getting Started Tutorial

Typical Display:

12A
rms

1000VDC

500Vpk

1.2A
rms

1.25A/500V FH

LO

CAT II (300V)

750VAC

HI

I

V

12A

Fused

+

-

Capacitance

μ F

μ F

Range

Temp

Temp

Typical Display:

12A
rms

1000VDC

500Vpk

1.2A
rms

1.25A/500V FH

LO

CAT II (300V)

750VAC

HI

I

V

12A

Fused

Test

Current

5k Ohm

Thermistor

°C

Measuring Capacitance

• Eight ranges: 1nF, 10nF, 100nF, 1µF, 10µF, 100µF, 1000µF, 10,000µF and autorange

• Measurement Method: Computed from constant current source charge time. Typical 0.2V - 1.4V AC

signal level

• Input Protection: 1000 V (HI terminal)

Measuring Temperature

• -80.0°C to 150.0 °C, -110.0°F to 300.0 °F

• Auto-ranging measurement, no manual range selection

• Measurement Method: 2-wire Ohms measurement of 5 kΩ thermistor sensor (E2308A) with

computed conversion

• Input Protection: 1000 V (HI terminal)

24 34405A User’s and Service Guide

Selecting a Range

Shift

Auto

You can let the multimeter automatically select the range using
autoranging, or you can select a fixed range using manual ranging.
Autoranging is convenient because the multimeter automatically selects the
appropriate range for sensing and displaying each measurement. However,
manual ranging results in better performance, since the multimeter does
not have to determine which range to use for each measurement.

Getting Started Tutorial 1

Selects a lower range and disables autoranging.

Selects a higher range and disables autoranging.

Selects autoranging and disables manual ranging.

• The ManRng annunciator is on when manual range is enabled.

• Autoranging is selected at power- on and after a remote reset.

• Manual ranging – If the input signal is greater than can be measured

on the selected range, the multimeter provides these overload
indications: OL from the front panel or “
interface.

• For frequency measurements, ranging applies to the signal’s input

voltage, not its frequency.

• The range is fixed for continuity (1 kΩ range) and diode (1 VDC range).

• The multimeter remembers the selected ranging method (auto or

manual) and the selected manual range for each measurement function.

• Autorange thresholds – The multimeter shifts ranges as follows:
Down range at <10% of current range
Up range at >120% of current range

• For remote operation, refer to the MEASure Subsystem in the Keysight
34405A Online Programmer’s Reference online help.

34405A User’s and Service Guide 25

\9.9E+37” from the remote

1 Getting Started Tutorial

Shift

4

Shift

Temp

5

Temp

Setting the Resolution

You can select either 4½ or 5½- digit resolution for the DCV, DCI,
resistance, ACV, ACI and frequency measurement functions.

• 5½- digit readings have the best accuracy and noise rejection.

• 4½- digit readings provide for faster readings.

• The continuity and diode test functions have a fixed, 4½-digit display.

• Capacitance and temperature have a fixed 3½- digit display.

Selects 4½- digit mode.

Selects 5½- digit mode.

• For remote operation, refer to the MEASure Subsystem in the Keysight
34405A Online Programmer’s Reference online help.

26 34405A User’s and Service Guide

34405A 5 ½ Digit Multimeter
User’s and Service Guide

2 Features and Functions

Math Operations 28
Using the Secondary Display 33
Using the Utility Menu 36
Editing Values in the Secondary Display 40
Storing and Recalling Instrument States 41
Reset/Power-On State 43
Triggering the Multimeter 45

This chapter contains detailed information on the multimeter
and how to use the front panel. It builds on information you
learned in the Quick Start Guide and the previous Getting
Started Tutorial Chapter.

2 Features and Functions

Math Operations

The table below describes the math operations that can be used with each
measurement function.

Measurement
Function

DCV    

DCI 

Ohms 

ACV    

ACI 

Frequency 

Capacitance 

Te m p e r a t u r e 

Continuity

Diode

Allowed Math Operations

Null dBm dB Min/Max Limit Hold

• All math operations can be toggled on and off by re- selecting the same
math operation.

• Only one math operation can be turned- on at a time. Selecting another
math operation when one is already on turns off the first operation and
then turns on the second math operation.

• All math operations are automatically turned- off when changing
measuring functions.

• Range changing is allowed for all math operations.

• For remote operation, refer to the CALCulate Subsystem in the Keysight

34405A Online Programmer’s Reference online help.

28 34405A User’s and Service Guide

Features and Functions 2

Null

Null

Shift

dBm

MnMx

Null

When making null measurements, also called relative, each reading is the
difference between a stored null value and the input signal. For example,
this feature can be used to make more accurate resistance measurements
by nulling the test lead resistance.

After you enable the Null operation, the multimeter stores the next
reading into the Offset register and immediately displays on the primary
display:

Primary Display = Reading - Offset

You can view and edit the Offset value in the secondary display as
described in “Editing Values in the Secondary Display” on page 40.

The multimeter allows Null settings for the following measurement
functions: DC Volts, AC Volts, DC Current, AC Current, Resistance,
Frequency, Capacitance and Temperature.

dBm

The logarithmic dBm (decibels relative to one milliwatt) scale is often
used in RF signal measurements. The multimeter’s dBm operation takes a
measurement and calculates the power delivered to a reference resistance
(typically 50, 75 or 600W). The formula used for conversion from the
voltage reading is:

dBm = 10 x Log

[ (Reading2 / R

10

) / 0.001W ]

REF

You can choose from several reference resistance values:

R

= 2Ω, 4Ω, 8Ω, 16Ω, 50Ω, 75Ω, 93Ω, 110Ω, 124Ω, 125Ω, 135Ω, 150Ω,

REF

250Ω, 300Ω, 500Ω, 600Ω, 800Ω, 900Ω, 1000Ω, 1200Ω, or 8000Ω.

Numeric results are in the range of ± 120.000 dBm with 0.01 dBm
resolution shown, independent of the number of digits setting.

You can v i ew a n d s e l ec t t he R

value in the secondary display as

REF

described in “Editing Values in the Secondary Display” on page 40.

34405A User’s and Service Guide 29

2 Features and Functions

dB

Null

Null

Shift

MnMx

dB

When enabled, the dB operation computes the dBm value for the next
reading, stores the dBm result into the dB Ref register and immediately
produces the following calculation. The first displayed reading is always
precisely 000.00 dB.

dB = 10 x Log10 [ (Reading2 / R

) / 0.001W ] - dB Ref

REF

• You can set dB Ref to any value between 0 dBm and \120.0000 dBm.
The default R

is 0 dBm.

REF

• Numeric results are displayed in the range of ± 120.000 dB with 0.01
dB resolution shown, independent of the number of digits setting.

You can view and edit the dB Ref Value in the secondary display as
described in “Editing Values in the Secondary Display” on page 40. The dB
Ref value is displayed on the secondary display in the range of ± 120.000
dBm with 0.001 dBm resolution shown.

Min/Max

The Min/Max (Minimum/Maximum) operation stores the minimum and
maximum values, the average, and the number of readings during a series
of measurements.

When enabled, the Min/Max operation turns on the MnMx annunciator
and begins accumulating various statistics about the readings being
displayed.

Each time a new minimum or maximum value is stored, the instrument
beeps once (if the beeper is enabled) and briefly turns on the appropriate
Max or Min annunciator. The multimeter calculates the average of all
readings and records the number of readings taken since Min/Max was
enabled.

• Accumulated statistics are:

• Max- - maximum reading since Min/Max was enabled

• Min- - minimum reading since Min/Max was enabled

• Avg-- average of all readings since Min/Max was enabled

• N- - number of readings taken since Min/Max was enabled

30 34405A User’s and Service Guide

Features and Functions 2

Disp

Limit

Shift

Hold

Limit

When Min/Max is enabled, pressing steps through the various Max,
Min, Avg, and N values in the secondary display. Count values display in
integer format until the maximum display value (120000) is reached after
which counts are displayed in scientific notation.

Limit

The Limit operation allows you to perform pass/fail testing against
specified upper and lower limits. You can set the upper and lower limits
to any value between 0 and \120% of the highest range for the present
function.

• You should specify the upper limit to always be a more positive number
than the lower limit. The initial factory setting for each limit is 0.

• The secondary display shows PAS S when readings are within the
specified limits. The secondary display shows HI when the reading is
outside the high limit and LO when the reading is outside the low limit.

• When the beeper is ON (see “Using the Utility Menu” on page 36) the
beeper beeps on the transition from PASS to HI or PASS to LO or
when transitioning directly from HI to LO or LO to HI (no PASS in
between).

You can view and edit HI Limit and LO Limit values in the secondary
display as described in “Editing Values in the Secondary Display” on

page 40.

Hold

The reading hold feature allows you to capture and hold a stable reading
on the front panel display. When a stable reading is detected, the
multimeter emits a beep (if the beeper is enabled) and holds the reading
on the primary display. The secondary display shows the present reading.

When enabled, the Hold operation turns on the Hold annunciator and
begins evaluating readings using the rules described below:

Primary Display = Reading

34405A User’s and Service Guide 31

IF Max() - Min() ≤ 0.1% x Reading

N

N

2 Features and Functions

NOTE

The decision to update a new reading value in the primary display is
based upon the box- car moving statistics of the present reading and the
three previous readings as described below:

Max (ReadingN Reading

Min (Reading

Reading

N

Reading

N-1

Reading

N-1

Reading

N-2

Reading

N-2

N-3

N-3

)

)

• Minimum delta value to trigger an update on held value : 0.1% of full scale

• Minimum level to enable update on held value : 5% of full scale

Math Annunciators

The math Hold, Limit, Null and MnMx annunciators are located above the
primary display and the dB/dBm annunciator is located right of the
primary display (see “The Display at a Glance” on page 16). The Math
Value Annunciators are located under the secondary display and assist in
viewing and editing math values in the secondary display.

Tab l e 1 Math Value Annunciators

Math Operation When Viewing/Editing Editable Math Annunciator

Null Offset  Ref Value

dBm R

dB dB Ref  Ref Value

REF

 Ref R Value

MnMx Maximum Max

Minimum Min

Average Avg

Reading Count N

Limit HI Limit  Hi Limit

LO Limit  Lo Limit

32 34405A User’s and Service Guide

Using the Secondary Display

mV DC

mV DC

Range

VAC

Hz

Disp

Most measurement functions have predefined range or measurement
capabilities that can be displayed in the secondary display. All math
operations have predefined operations that are displayed on the secondary
display.

Measurement Functions and the Secondary Display

When making measurements, the secondary display allows you to show the
measurement range (for most measurement functions) or to select a
predefined secondary measurement function. For example, a typical
primary display showing DCV and a secondary display showing the DCV
range is:

Features and Functions 2

As another example, a typical primary display showing ACV and a
secondary display showing the measured frequency of the input signal is:

The secondary display is based on the selected primary measurement
function and how many times you press:

34405A User’s and Service Guide 33

2 Features and Functions

Disp

The table below shows the secondary display capabilities for all
measurement functions.

Repeatedly pressing cycles through the secondary display choices
for the present measurement function as shown in the table below. The
temperature, continuity and diode functions do not have secondary
displays.

.

Primary Display Default Secondary Display Press Disp Key Once Press Disp Key Twice

DCV DCV range ACV Off

DCI DCI range ACI Off

Resistance Resistance range Off Resistance Range

ACV ACV range Frequency Off

ACI ACI range Frequency Off

Frequency AC Voltage Range ACV Off

Capacitance Capacitance range Off Capacitance Range

Secondary Display

Temperature Off Off Off

Continuity Off Off Off

Diode Test Off Off Off

• When a second measurement function is selected, its resolution will
match the primary measurement setting and, whenever possible, it will
use autorange.

• Enabling any math operation turns off the secondary display for
measurements. All math operations offer predefined displays that can
be presented on the secondary display as described on the next page.

• For remote operation, refer to the DISPlay:WINDow2 commands in the
Keysight 34405A Online Programmer’s Reference online help.

34 34405A User’s and Service Guide

Features and Functions 2

mV DC

Limit

Disp

Math Operations and the Secondary Display

When a math operation is selected, the secondary display shows the result
of the math operation or the value(s) being used by the math operation.
For example, a typical primary display showing the Limit math operation
for DCV measurements and a secondary display showing a HI limit
exceeded is:

Repeatedly pressing cycles through the secondary display choices
for the present math operation as shown in the table below. (Reading is
used in the table below to indicate the original measured reading value.)

Secondary Display

Default Secondary

Math Operation Primary Display

Null Nulled Reading Reference Value Off

dBm dBm Present Reading R

dB dB Present Reading dB Ref (in

Min/Max Reading Max value Min value Avg value N (count) value Off

Limit Reading PASS

Hold Held Reading Present Reading Off

Display

HI
LO

Press Disp
Key Once

REF

dBm)

HI Limit LO Limit Off

Press Disp
Key Twice

Off

Off

Press Disp
Key Three Times

Press Disp
Key Four Times

34405A User’s and Service Guide 35

2 Features and Functions

Using the Utility Menu

The Utility Menu allows you to customize a number of non- volatile
instrument configurations. It also displays error messages and hardware
revision codes. The contents of the Utility Menu are shown in the table
below.

Secondary

Primary Display

Display Settings Description Remote Command

tESt no YES IF YES, immediately execute self-test

upon next Store/Recall button push.
After self-test completes, returns to
normal instrument operation.

ºunit ºC ºF Changes displayed units for temperature

measurements

bEEP On OFF Enable, disable Diode, Min/Max, Limit

Test, and Hold beep operations

P-On rESEt LASt Enable or disable power-on recall of State

0 (last power-off instrument state). Note:
The multimeter always saves the
power-down state. This just determines
whether or not to recall the state at
power-on.

2.diSP On OFF Turn the secondary display on or off. DISPlay:WINDow2[:STATe] <mode>

StorE On OFF Enable, disable all front panel state store

operation

Edit On OFF Enable, disable all math register editing None

Error nonE nn.Err See Reading Error Messages below. SYSTem:ERRor?

CodE 1-dd.d 2-dd.d Displays processor code revision

numbers.
1= Measurement processor revision.
2= IO processor revision.

*TST? (self-test is executed
immediately)

UNIT:TEMPerature <units>

SYSTem:BEEPer:STATe <mode>

MEMory:STATe:RECall:AUTO <mode>

MEMory:STATe:STORe <mode>

*IDN? (from remote also returns
manufacturer's name, model number,
and the serial number)

UtitY donE Display donE on primary display for 1

second then return to normal operation

None

36 34405A User’s and Service Guide

Features and Functions 2

Shift

Utility

Store

Recall

Store

Recall

Store

Recall

Store

Recall

Edit

NOTE

Changing Configurable Settings

The first seven items in the Utility Menu are configurable (Error and
CodE are not configurable).

1 To access the Utility Menu, press .

2 The first Utility Menu selection (tESt) is shown in the primary display.

When stepping through the configurable items, the present setting for
each item is displayed in the secondary display.

3 To change the setting, use the and keys to select the

setting you want.

4 When the correct setting is displayed in the secondary

display, press to save the setting and advance to the next
item.

If you set tESt to On, pressing Store/Recall immediately exits the Utility Menu and
executes self-test. If you set tESt to OFF, go on to the next step (step 5).

5 Repeat steps 4 and 5 for all items in the Utility Menu.

6 When you reach the end of the Utility Menu, the primary display shows

utitY and the secondary display briefly shows donE, after which the
multimeter returns to normal operation.

34405A User’s and Service Guide 37

2 Features and Functions

Shift

Utility

Store

Recall

Store

Recall

Store

Recall

Store

Recall

Edit

Store

Recall

Store

Recall

Edit

Reading Error Messages

The following procedure shows you to read error messages from the front
panel. For remote operation, refer to the SYSTem:ERRor? command in the
Keysight 34405A Online Programmer’s Reference online help.

1 To access the Utility Menu, press

2 Press seven times until Error is shown in the primary display.

3 If there are no errors in the error queue, the secondary display shows

nonE.

If there are one or more errors, Error is shown in the primary display
and nn.Err is shown flashing in the secondary display (where nn is the
total number of errors in the error queue). For example, if there are
three errors in the queue, 03.Err will flash in the secondary display.
Errors are numbered and stored in the queue in the order they
occurred.

4 If there are errors in the error queue, press to read the first

error. The error number in the queue is shown in the primary display
and the actual error number is shown in the secondary display.

5 Repeat step 4 for all errors in the error queue

(you can also use to view the previous error).

6 After reading all errors,

press twice to exit the Utility Menu.

7 The error queue is automatically cleared after has been pressed

and the utility menu is exited.

38 34405A User’s and Service Guide

Features and Functions 2

The Beeper

Normally, the multimeter beeps whenever certain conditions are met (for
example, the multimeter beeps when a stable reading is captured in
reading hold mode). The beeper is factory set to ON, but may be disabled
or enabled manually.

• Turning off the beeper does not disable the key click generated when
you press a front-panel key.

• A beep tone is always emitted (even with the beep state turned OFF) in
the following cases.

• A continuity measurement is less than or equal to the continuity

threshold.

• A SYSTem:BEEPer command is sent.

• An error is generated.

• In addition to the beep operations just described, when the beeper is

ON, a single beep occurs for the following cases (turning the beeper
OFF disables the beep for the following cases):

• When a new Min or Max value is stored

• When a new stable reading is updated on display for Math Hold

operation

• When a measurement exceeds the HI or LO Limit value

• When a forward- biased is measured in the Diode function

34405A User’s and Service Guide 39

2 Features and Functions

Disp

Limit

Edit

Limit

Edit

Store

Recall

Store

Recall

Edit

Disp

Editing Values in the Secondary Display

Many Math function values are editable in the secondary display. The
table below describes key operations during number editing. These rules
also apply for editing within the Utility menu.

You can edit the values used for the Null, Limit, dB or dBM math
function. For remote operation, refer to the CALCulate Subsystem in the
Keysight 34405A Online Programmer’s Reference online help.

Selecting the Value to Edit

With the math function enabled, press until the Ref Value, Ref
R Value, Hi Limit or Lo Limit you want to edit is displayed in the

secondary display.

To select the editing mode, press:

The secondary display will briefly show Edit to indicate you are in editing
mode.

Editing Values

Use these keys to position the cursor on a digit:

Moves cursor to the left

Moves cursor to the right

When the cursor is positioned on a digit, use these keys to edit the value:

Increments digit Decrements digit

When done editing, save the new value by pressing:

40 34405A User’s and Service Guide

Storing and Recalling Instrument States

NOTE

Store

Recall

Store

Recall

Store

Recall

Store

Recall

Store

Recall

Store

Recall

You can save and recall complete instrument states including all front
panel settings, all math registers, all Utility Menu settings, and all bus
specific settings. There are four user storage registers numbered 1 through

4. An additional state, state 0, is managed by the instrument and stores

the last power- down state. The instrument automatically saves the
complete instrument configuration to State 0 whenever a power- down
event occurs.

For remote operation, refer to the MEMory Subsystem, the *SAV, and *RCL
commands in the Keysight 34405A Online Programmer’s Reference online
help.

The store function in the utility menu must be enabled (On) before you can store states.
Refer to “Using the Utility Menu” on page 36 for details.

Features and Functions 2

Storing a State

Before storing an instrument state, select the measurement function,
range, math operations, and so on, that you want saved as a state. To
store the instrument state:

1 Press , the display Store and Recall annunciators will begin

flashing.

2 Press or until only the Store annunciator is flashing.

3 Press again.

4 Press or until the state number (1- 4) you want to use is

shown flashing in the secondary display.

5 Press to store the state. The secondary display briefly shows

donE when the state is successfully saved.

34405A User’s and Service Guide 41

2 Features and Functions

NOTE

Store

Recall

Store

Recall

Store

Recall

Store

Recall

Store

Recall

Store

Recall

Store

Recall

Store

Recall

NOTE

Store

Recall

Store

Recall

To escape the recall operation without recalling a state, select ESC in step 4 above and

press to escape. After escaping, the secondary display briefly shows - - -

Recalling a Stored State

To recall an instrument state:

1 Press , the display Store and Recall annunciators will begin

flashing.

2 Press or until only the Recall annunciator is flashing.

3 Press again.

4 Press or until the state number you want to recall is

shown flashing in the secondary display. You can select state 1 through
4 or LASt for the power- down state. To exit without recalling a state,
select ESC.

5 Press to perform the recall (or ESC) operation. When finished,

the secondary display briefly shows donE.

To escape the recall operation without recalling a state, select ESC in step 4 above and

press to escape. After escaping, the secondary display briefly shows - - -

42 34405A User’s and Service Guide

Features and Functions 2

Reset/Power-On State

The table below summarizes the 34405A's settings as received from the
factory, following power cycling, and following the *RST command received
over the USB remote interface. Non- volatile, user customizable behavioral
differences are shown in BOLD type.

Tab l e 2 Reset/Power-On State

Parameter Factory Setting Power-on / Reset State

Measurement Configuration

Function DCV DCV

Range AUTO AUTO

Resolution 5-½ digits 5-½ digits

Tem p er at ur e U nit s °C User setting

Math Operations

Math State, Function Off, Null Off, Null

Math Registers Cleared Cleared

dBm Reference Resistance 600Ω User setting

Math Register Editing On User setting

Trigger Operations

Trigger Source* Auto Trigger (Local Mode)

IMMediate (Remote Mode)

System-Related Operations

Power-Down Recall Disabled User Setting

Stored States 0-4 cleared No Change

Beeper On User Setting

Display On On

Remote/ Local State* Local Local

Keyboard* Unlocked, Local key enabled Unlocked, Local key enabled

Auto Trigger (Local Mode)
IMMediate (Remote Mode)

34405A User’s and Service Guide 43

2 Features and Functions

Tab l e 2 Reset/Power-On State

Parameter Factory Setting Power-on / Reset State

Reading Output Buffer* Cleared Cleared

Error Queue* Cleared Cleared

Power-on Status Clear* Last User Setting

Status Registers, Masks & Transition
Filters*

Serial Number Unique value per-instrument No Change

Calibration

Calibration state Secured User Setting

Calibration value 0 No Change

Calibration String Cleared No Change

Cleared Cleared if power-on status clear

enabled; no change otherwise

*State managed by IO Processor firmware.

44 34405A User’s and Service Guide

Triggering the Multimeter

From the front panel (Local mode), the multimeter always auto–triggers.
Auto triggering takes continuous readings at the fastest rate possible for
the selected measurement configuration.

From the remote interface, triggering the multimeter is a three–step
process:

1 Configure the multimeter for the measurement by selecting the

function, range, resolution, and so on.

2 Specify the multimeter’s trigger source. Choices are a software (bus)

trigger from the remote interface or an immediate internal trigger
(default trigger source).

3 Ensure that the multimeter is ready to accept a trigger from the

specified source (called the wait–for–trigger state).

Immediate Triggering

The immediate triggering mode is available from the remote interface only.

In the immediate trigger mode, the trigger signal is always present. When
you place the multimeter in the wait–for–trigger state, the trigger is issued
immediately. This is the default trigger source for remote interface
operation.

Features and Functions 2

• Remote Interface Operation: The following command selects the immediate
trigger source:

TRIGger:SOURce IMMediate

The CONFigure and MEASure? commands automatically set the trigger
source to IMMediate.

Refer to the Keysight 34405A Programmer’s Reference for complete
description and syntax for these commands.

Software (Bus) Triggering

The bus trigger mode is available from the remote interface only.

The bus trigger mode is initiated by sending a bus trigger command, after
selecting BUS as the trigger source.

• The TRIGger:SOURce BUS command selects the bus trigger source.

34405A User’s and Service Guide 45

2 Features and Functions

• The MEASure? command overwrites the BUS trigger and triggers the
DMM and returns a measurement.

• The READ? command does not overwrite the BUS trigger, and if
selected, generates an error. It will only trigger the instrument and
return a measurement when the IMMEdiate trigger is selected.

• The INITiate command only initiates the measurement and needs a
trigger (BUS or IMMEdiate) to make the actual measurement.

Refer to the Keysight 34405A Programmer’s Reference for complete
description and syntax for these commands.

46 34405A User’s and Service Guide

34405A 5 ½ Digit Multimeter
User’s and Service Guide

3 Measurement Tutorial

DC Measurement Considerations 48
Noise Rejection 49
Resistance Measurement Considerations 51
True RMS AC Measurements 53
Other Primary Measurement Functions 56
Other Sources of Measurement Error 59

The Keysight 34405A multimeter is capable of making very
accurate measurements. In order to achieve the greatest
accuracy, you must take the necessary steps to eliminate
potential measurement errors. This chapter describes
common errors found in measurements and gives suggestions
to help you avoid these errors.

3 Measurement Tutorial

DC Measurement Considerations

Thermal EMF Errors

Thermoelectric voltages are the most common source of error in low–level
DC voltage measurements. Thermoelectric voltages are generated when you
make circuit connections using dissimilar metals at different temperatures.
Each metal–to–metal junction forms a thermocouple, which generates a
voltage proportional to the junction temperature. You should take the
necessary precautions to minimize thermocouple voltages and temperature
variations in low–level voltage measurements. The best connections are
formed using copper–to–copper crimped connections, as the multimeter’s
input terminals are a copper alloy. The table below shows common
thermoelectric voltages for connections between dissimilar metals.

Copper to – Approx. mV / °C Copper to – Approx. mV / °C

Cadmium-Tin Solder 0.2 Aluminum 5
Copper <0.3 Tin-Lead Solder 5
Gold 0.5 Kovar or Alloy 42 40
Silver 0.5 Silicon 500
Brass 3 Copper-Oxide 1000
Beryllium Copper 5

48 34405A User’s and Service Guide

Noise Rejection

V

f

R

s

R

i

C

i

Ideal

Meter

Vf = Float Voltage
R

s

= DUT Source Resistance
Imbalance
R

i

= Multimeter Isolation Resistance
(LO-Earth)
C

i

= Multimeter Input Capacitance:

V

f

x R

s

Error (v) =

R

s

+ R

i

HI

LO

V

test

Rejecting Power–Line Noise Voltages

A desirable characteristic of integrating analog–to–digital (A/D) converters
is their ability to reject power–line related noise present with DC input
signals. This is called normal mode noise rejection, or NMR. The
multimeter achieves NMR by measuring the average DC input by
"integrating" it over a fixed period.

Common Mode Rejection (CMR)

Ideally, a multimeter is completely isolated from earth–referenced circuits.
However, there is finite resistance between the multimeter's input LO
terminal and earth ground, as shown below. This can cause errors when
measuring low voltages which are floating relative to earth ground.

Measurement Tutorial 3

Refer to “Measurement Noise Rejection” on page 130 for the multimeter’s
NMR and CMR characteristics.

Noise Caused by Magnetic Loops

If you are making measurements near magnetic fields, take caution to
avoid inducing voltages in the measurement connections. You should be
especially careful when working near conductors carrying large currents.
Use twisted–pair connections to the multimeter to reduce the noise pickup
loop area, or dress the test leads as close together as possible. Loose or

34405A User’s and Service Guide 49

3 Measurement Tutorial

Ideal

Meter

R

L

R

L

HI

LO

V

ground

V

test

Ri > 10 GΩ

R

L

= Lead Resistance

R

i

= Multimeter Isolation Resistance

V

ground

= Voltage Drop on Ground Bus

vibrating test leads will also induce error voltages. Tie down test leads
securely when operating near magnetic fields. Whenever possible, utilize
magnetic shielding materials or increased distance from magnetic sources.

Noise Caused by Ground Loops

When measuring voltages in circuits where the multimeter and the device
under test are both referenced to a common earth ground, a ground loop
is formed. As shown below, any voltage difference between the two ground
reference points (V
measurement leads. This causes noise and offset voltage (usually
power–line related), which are added to the measured voltage.

) causes a current to flow through the

ground

The best way to eliminate ground loops is to isolate the multimeter from
earth by not grounding the input terminals. If the multimeter must be
earth–referenced, connect it and the device under test to the same
common ground point. Also connect the multimeter and device under test
to the same electrical outlet whenever possible.

50 34405A User’s and Service Guide

Resistance Measurement Considerations

Null

Null

When measuring resistance, the test current flows from the input HI
terminal through the resistor being measured. The voltage drop across the
resistor being measured is sensed internal to the multimeter. Therefore,
test lead resistance is also measured.

The errors mentioned earlier in this chapter for DC voltage measurements
also apply to resistance measurements. Additional error sources unique to
resistance measurements are discussed here.

Removing Test Lead Resistance Errors

To eliminate offset errors associated with the test lead resistance in
2–wire ohms measurements, follow the steps below.

1 Connect the ends of the test leads together. The multimeter displays the

test lead resistance.

2 Press . The multimeter stores the test lead resistance as the

2–wire ohms null value, and subtracts that value from subsequent
measurements.

Measurement Tutorial 3

Minimizing Power Dissipation Effects

When measuring resistors designed for temperature measurements (or
other resistive devices with large temperature coefficients), be aware that
the multimeter will dissipate some power in the device under test.

If power dissipation is a problem, you should select the multimeter's next
higher measurement range to reduce the errors to acceptable levels. The
following table shows several examples.

Range Test Current DUT

Power at Full Scale

100 Ω 1 mA 100 mW
1 k Ω 0.83 mA 689 mW
1 0 k Ω 100 mA 100 mW
100 kΩ 10 mA 10 mW
1 M Ω 900nA 810 nW

34405A User’s and Service Guide 51

3 Measurement Tutorial

AC Reading = √ Average [Data (1:25)]

2

Errors in High Resistance Measurements

When you are measuring large resistances, significant errors can occur
due to insulation resistance and surface cleanliness. You should take the
necessary precautions to maintain a "clean" high–resistance system. Test
leads and fixtures are susceptible to leakage due to moisture absorption in
insulating materials and "dirty" surface films. Nylon and PVC are relatively
poor insulators (10

13

(10

0.1% error when measuring a 1 MW resistance in humid conditions.

AC Measurements

Each single ACV or ACI measurement is computed based upon a RMS
(root- mean- square) value calculated on an array of 25 sequential A/D
converter samples acquired with constant sample- to- sample timing.
Samples are acquired at a rate very close to the maximum trigger- settle
rate for the A/D converter as shown below.

10 MΩ 205 nA 420 nW
100 MΩ 205 nA ||10 MΩ 35 nW

9

W) when compared to PTFE insulators

W). Leakage from nylon or PVC insulators can easily contribute a

When configured for an ACV or ACI measurement, the multimeter acquires
an array of 25 sequential samples which comprise the AC reading data
set. The final AC reading result is computed from the acquired data set
as shown by the equation below:

52 34405A User’s and Service Guide

True RMS AC Measurements

Waveform Shape Crest Factor AC RMS AC + DC RMS

True RMS responding multimeters, like the Keysight 34405A, measure the
"heating" potential of an applied voltage. Power dissipated in a resistor is
proportional to the square of an applied voltage, independent of the
waveshape of the signal. This multimeter accurately measures true RMS
voltage or current, as long as the wave shape contains negligible energy
above the instrument’s effective bandwidth.

Note that the 34405A uses the same techniques to measure true RMS
voltage and true RMS current.

Measurement Tutorial 3

The multimeter's AC voltage and AC current functions measure the
AC–coupled true RMS value. In this Keysight instrument, the “heating
value” of only the AC components of the input waveform are measured (DC
is rejected). As seen in the figure above; for sinewaves, triangle waves, and
square waves, the AC–coupled and AC+DC values are equal,
waveforms do not contain a DC offset. However, for non–symmetrical
waveforms, such as pulse trains, there is
rejected by Keysight’s AC–coupled true RMS measurements. This can
provide a significant benefit.

34405A User’s and Service Guide 53

a DC voltage content, which is

since these

3 Measurement Tutorial

An AC–coupled true RMS measurement is desirable when you are
measuring small AC signals in the presence of large DC offsets. For
example, this situation is common when measuring AC ripple present on
DC power supplies. There are situations, however, where you might want
to know the AC+DC true RMS value. You can determine this value by
combining results from DC and AC measurements, as shown below:

For the best AC noise rejection, you should perform the DC measurement
at 5½- digits.

True RMS Accuracy and High–Frequency Signal Content

A common misconception is that "since an AC multimeter is true RMS, its
sine wave accuracy specifications apply to all waveforms." Actually, the
shape of the input signal can dramatically affect measurement accuracy,
for any multimeter, especially when that input signal contains
high–frequency components which exceed the instrument’s bandwidth.
Error in RMS measurements arise when there is significant input signal
energy at frequencies above the multimeter’s bandwidth.

Estimating High–Frequency (Out–of–Band) Error

A common way to describe signal waveshapes is to refer to their “Crest
Factor”. Crest factor is the ratio of the peak value to RMS value of a
waveform. For a pulse train, for example, the crest factor is approximately
equal to the square root of the inverse of the duty cycle.

Notice that crest factor is a composite parameter, dependent upon the
pulse–width and repetition frequency; crest factor alone is not enough to
characterize the frequency content of a signal.

Traditionally, DMMs include a crest factor derating table that applies at all
frequencies. The measurement algorithm used in the 34405A multimeter is
not inherently sensitive to crest factor, so no such derating is necessary.

54 34405A User’s and Service Guide

Measurement Tutorial 3

p

t

f

1

1

=

prfCFf ⋅=

2

1

With this multimeter, as discussed in the previous section, the focal issue
is high–frequency signal content which exceeds the multimeter’s
bandwidth.

For periodic signals, the combination of crest factor and repetition rate
can suggest the amount of high–frequency content and associated
measurement error. The first zero crossing of a simple pulse occurs at

This gives an immediate impression of the high- frequency content by
identifying where this crossing occurs as a function of crest
factor:

The following table shows the typical error for various pulse waveforms as
a function of input pulse frequency:

Typical error for square wave, triangular wave, and pulse trains of CF=3, 5, or 10

prf square wave triangle wave CF=3 CF=5 CF=10

200 –0.02% 0.00% –0.04% –0.09% –0.34%
1000
2000
5000
10000
20000
50000
100000

–0.07% 0.00% –0.18% –0.44% –1.71%
–0.14% 0.00% –0.34% –0.88% –3.52%
–0.34% 0.00% –0.84% –2.29% –8.34%
–0.68% 0.00% –1.75% –4.94% –26.00%
–1.28% 0.00% –3.07% –8.20% –45.70%
–3.41% –0.04% –6.75% –32.0% –65.30%
–5.10% –0.12% –21.8% –50.6% –75.40%

This table gives an additional error for each waveform, to be added to the
value from the accuracy table provided in the Specifications chapter.

Example: A pulse train with level 1 V

, is measured on the 1 V range. It

rms

has pulse heights of 3 V (that is, a Crest Factor of 3) and duration 111 ms.
The prf can be calculated to be 1000 Hz, as follows:

Thus, from the table above, this AC waveform can be measured with 0.18
percent additional error.

34405A User’s and Service Guide 55

3 Measurement Tutorial

Vs = Source Voltage
R

s

= DUT Source Resistance

V

b

= Multimeter Burden Voltage

R = Multimeter Current Shunt

Error (%) =

-100% x V

b

V

s

Ideal

Meter

R

I

LO

V

b

R

s

V

s

Other Primary Measurement Functions

Frequency Measurement Errors

The multimeter uses a reciprocal counting technique to measure
frequency. This method generates constant measurement resolution for any
input frequency. All frequency counters are susceptible to errors when
measuring low–voltage, low–frequency signals. The effects of both internal
noise and external noise pickup are critical when measuring "slow" signals.
The error is inversely proportional to frequency. Measurement errors also
occur if you attempt to measure the frequency of an input following a DC
offset voltage change. You must allow the multimeter's input to fully settle
before making frequency measurements.

DC Current Measurements

When you connect the multimeter in series with a test circuit to measure
current, a measurement error is introduced. The error is caused by the
multimeter's series burden voltage. A voltage is developed across the
wiring resistance and current shunt resistance of the multimeter, as
shown below.

56 34405A User’s and Service Guide

Capacitance Measurements

Measurement Model

(during charge phase)

Measurement Model

(during discharge phase)

C

offset

V

charge

d

C

R'

R

P

C

C

offset

The multimeter implements capacitance measurements by applying a
known current to the capacitor as shown below:

Capacitance is calculated by measuring the change in voltage (DV) that
occurs over a “short aperture” time, (Dt). The measurement cycle consists
of two parts: a charge phase and a discharge phase.

The values of capacitance and loss resistance measured with the
multimeter may differ from the values measured using an LCR meter. This
is to be expected, since this is essentially a DC measurement method,
while LCR measurement uses applied frequencies anywhere from 100 Hz
to 100 kHz. In most cases, neither method measures the capacitor at its
exact frequency of application.

For the best accuracy, take a zero null measurement with open probes, to
null out the test lead capacitance, before connecting the probes across the
capacitor to be measured.

Measurement Tutorial 3

34405A User’s and Service Guide 57

3 Measurement Tutorial

Temperature Measurements

The multimeter measures temperature by measuring the temperature
sensitive resistance of 5 kW thermistors.

Thermistors consist of semiconductor materials and provide roughly 10
times the sensitivity of an RTD. Because they are semiconductors, their
temperature range is more limited, commonly to –80
Thermistors have highly non–linear temperature–resistance relationships;
therefore their conversion algorithms are more complex. Keysight
multimeters use the standard Hart–Steinhart Approximation to provide
accurate conversions.

o

C to 150 oC.

58 34405A User’s and Service Guide

Other Sources of Measurement Error

Error (%) =

-100 x R

s

Rs + 1 MΩ

Error (%) =

R

s

= Source Resistance
F = Input Frequency
C

in

= Input Capacitance (100 pF) Plus Cable

Capacitance

Loading Errors (AC volts)

In the AC voltage function, the input of the multimeter appears as a 1 MW
resistance in parallel with 100 pF of capacitance. The cabling that you use
to connect signals to the multimeter also adds capacitance and loading.

For low frequencies, the loading error is:

At high frequencies, the additional loading error is:

Measurement Tutorial 3

Measurements Below Full Scale

You can make the most accurate AC measurements when the multimeter is
at or near the full scale of the selected range. Autoranging occurs at 10%
(down–range) and 120% (up–range) of full scale. This enables you to
measure some inputs at full scale on one range and 10% of full scale on
the next higher range. In general, the accuracy is better on the lower
range; for the highest accuracy, select the lowest manual range possible for
the measurement.

High–Voltage Self–Heating Errors

If you apply more than 300 V
internal signal–conditioning components. These errors are included in the
multimeter's specifications.

Temperature changes inside the multimeter due to self–heating may cause
additional error on other AC voltage ranges.

34405A User’s and Service Guide 59

, self–heating occurs in the multimeter's

rms

3 Measurement Tutorial

Voltage Measured = V

in

2

+ Noise

2

AC Current Measurement Errors (Burden Voltage)

Burden voltage errors, which apply to DC current, also apply to AC
current measurements. However, the burden voltage for AC current is
larger due to the multimeter's series inductance and your measurement
connections. The burden voltage increases as the input frequency
increases. Some circuits may oscillate when performing current
measurements due to the multimeter's series inductance and your
measurement connections.

Low–Level Measurement Errors

When measuring AC voltages less than 100 mV, be aware that these
measurements are especially susceptible to errors introduced by
extraneous noise sources. An exposed test lead acts as an antenna and a
properly functioning multimeter will measure the signals received. The
entire measurement path, including the power line, acts as a loop antenna.
Circulating currents in the loop create error voltages across any
impedances in series with the multimeter's input. For this reason, you
should apply low–level AC voltages to the multimeter through shielded
cables. You should connect the shield to the input LO terminal.

60 34405A User’s and Service Guide

Make sure the multimeter and the AC source are connected to the same
electrical outlet whenever possible. You should also minimize the area of
any ground loops that cannot be avoided. A high–impedance source is
more susceptible to noise pickup than a low–impedance source. You can
reduce the high–frequency impedance of a source by placing a capacitor in
parallel with the multimeter's input terminals. You may have to
experiment to determine the correct capacitor value for your application.

Most extraneous noise is not correlated with the input signal. You can
determine the error as shown below.

Correlated noise, while rare, is especially detrimental. Correlated noise
always adds directly to the input signal. Measuring a low–level signal with
the same frequency as the local power line is a common situation that is
prone to this error.

Measurement Tutorial 3

1

T

---

fx()xd

T



Pulse Measurement Error

You can use the DC measurement function to measure a pulse signal and
obtain its relevant average measurement quickly. The formula of the
equivalent DC average of a pulse signal is provided below.

where f(x) is the function representing the signal waveform over a period
of T.

Error may occur when the pulse signal is measured at low voltage range
due to saturation of the multimeter’s analog- to- digital (ADC) rail voltage.

34405A User’s and Service Guide 61

3 Measurement Tutorial

THIS PAGE HAS BEEN INTENTIONALLY LEFT BLANK.

62 34405A User’s and Service Guide

34405A 5 ½ Digit Multimeter

WARNING

User’s and Service Guide

4 Performance Tests and Calibration

Calibration Overview 64
Recommended Test Equipment 66
Test Considerations 67
Performance Verification Tests Overview 68
Performance Verification Tests 70
Calibration Security 82
Calibration Process 85
Adjustments 88
Calibration Errors 103

This chapter contains performance test procedures and
calibration procedures. The performance tests procedures
allow you to verify that the multimeter is operating within
its published specifications.

The calibration procedures show how to make zero and gain
adjustments to the multimeter.

SHOCK HAZARD. Only service–trained personnel who are aware of the hazards
involved should perform the procedures in this chapter. To avoid electrical shock and
personal injury, make sure to read and follow all test equipment safey instructions.

Use only completely electrically insulated test lead sets with connectors that
prevent contact with test voltages.

4 Performance Tests and Calibration

NOTE

Calibration Overview

Make sure you have read “Test Considerations” on page 67 before calibrating the
instrument.

Closed - Case Electronic Calibration

The instruments features closed- case electronic calibration. No internal
mechanical adjustments are required. The instrument calculates correction
factors based upon the input reference value you set. The new correction
factors are stored in non- volatile memory until the next calibration
adjustment is performed. Non - volatile EEPROM calibration memory does
not change when power has been off or after a remote interface reset

Keysight Technologies Calibration Services

When your instrument is due for calibration, contact your local Keysight
Service Center for a low-cost recalibration. The 34405A is supported on
automated calibration systems, which allow Keysight to provide this
service at competitive prices.

Calibration Interval

A 1- year interval is adequate for most applications. Accuracy
specifications are warranted only if adjustment is made at regular
calibration intervals. Accuracy specifications are not warranted beyond the
1- year calibration interval. Keysight does not recommend extending
calibration intervals beyond 2 years for any application.

64 34405A User’s and Service Guide

Performance Tests and Calibration 4

Time Required for Calibration

The 34405A can be automatically calibrated under computer control. With
computer control you can perform the complete calibration procedure and
performance verification tests in less than 30 minutes once the instrument
is warmed- up (see “Test Considerations” on page 67). Refer to the 34405A
Programmer’s Reference online help for more information.

34405A User’s and Service Guide 65

4 Performance Tests and Calibration

Recommended Test Equipment

The test equipment recommended for the performance verification and
adjustment procedures is listed below.If the exact instrument is not
available, substitute calibration standards of equivalent accuracy.

A suggested alternate method would be to use the Keysight 3458A 8½

- Digit Digital Multimeter to measure less accurate yet stable sources. The
output value measured from the source can be entered into the instrument
as the target calibration value.

Tab l e 3 Recommended Test Equipment

Application Recommended Equipment Recommended Accuracy Requirements

Zero Calibration Shorting Plug--Dual banana plug with copper wire

short between the two terminals

DC Voltage Fluke 5520A <1/5 instrument 1 year spec

DC Current Fluke 5520A <1/5 instrument 1 year spec

Resistance Fluke 5520A <1/5 instrument 1 year spec

AC Voltage Fluke 5520A <1/5 instrument 1 year spec

AC Current Fluke 5520A <1/5 instrument 1 year spec

Frequency Fluke 5520A <1/5 instrument 1 year spec

Capacitance Fluke 5520A <1/5 instrument 1 year spec

66 34405A User’s and Service Guide

Test Considerations

Errors may be induced by AC signals present on the input leads during a
self- test. Long test leads can also act as an antenna causing pick- up of AC
signals.

For optimum performance, all procedures should comply with the
following recommendations:

• Assure that the calibration ambient temperature is stable and between

18 °C and 28 °C. Ideally the calibration should be performed at 23 °C
±1 °C.

• Assure ambient relative humidity is less than 80%.

• Allow a 1- hour warm- up period with a Shorting Plug connected to the

HI and LO input terminals.

• Use shielded twisted pair PTFE- insulated cables to reduce settling and

noise errors. Keep the input cables as short as possible.

• Connect the input cable shields to earth ground. Except where noted in

the procedures, connect the calibrator LO source to earth ground at the
calibrator. It is important that the LO to earth ground connection be
made at only one place in the circuit to avoid ground loops.

Performance Tests and Calibration 4

Because the instrument is capable of making very accurate measurements,
you must take special care to ensure that the calibration standards and
test procedures used do not introduce additional errors. Ideally, the
standards used to verify and adjust the instrument should be an order of
magnitude more accurate than each instrument range full- scale error
specification.

Input Connections

Test connections to the instrument are best accomplished using the dual
banana plug with copper wire short between two terminals for
low- thermal offset measurement. Shielded, twisted- pair, PTFE interconnect
cables of minimum length are recommended between the calibrator and
the multimeter. Cable shields should be earth ground referenced. This
configuration is recommended for optimal noises and settling time
performance during calibration.

34405A User’s and Service Guide 67

4 Performance Tests and Calibration

Performance Verification Tests Overview

Use the Performance Verification Tests to verify the measurement
performance of the instrument. The performance verification tests use the
instrument's specifications listed in Chapter 6, “Specifications”.

You can perform four different levels of performance verification tests:

Self- Test A series of internal verification tests that give a high confidence
that the instrument is operational.

Quick Verification A combination of the internal self- tests and selected
verification test.

Performance Verification Tests An extensive set of tests that are
recommended as an acceptance test when you first receive the instrument
or after performing adjustments.

Optional Verification Tests Tests not performed with every calibration.
Perform these tests to verify additional specifications or functions of the
instrument.

Self -Test

• A brief power- on self- test occurs automatically whenever you turn on

the instrument. This limited test assures that the instrument is capable
of operation.

• During the self- test all display segments and annunciators are lit.

• If the self- test fails, an error is reported on the front panel. You can

also use the SYSTem: ERRor? command query from the remote
interface. If repair is required, contact a Keysight Service Center.

• If all tests pass, you have a high confidence (~90%) that the instrument

is operational.

• You can initiate a more complete self- test by sending the *TST?

command to the instrument. This command returns a "+0" if all the
self- tests pass, or a "+1" if a failure occurred. This command may take
up to 30 seconds to complete. You may need to set an appropriate
interface time- out value.

68 34405A User’s and Service Guide

Performance Tests and Calibration 4

Quick Performance Check

The quick performance check is a combination of internal self- test and an
abbreviated performance test (specified by the letter Q in the performance
verification tests). This test provides a simple method to achieve high
confidence in the instrument's ability to functionally operate and meet
specifications. These tests represent the absolute minimum set of
performance checks recommended following any service activity. Auditing
the instrument's performance for the quick check points (designated by a
Q) verifies performance for "normal" accuracy drift mechanisms. This test
does not check for abnormal component failures.

To perform the quick performance check, do the following:

• Perform a self- test as described in the preceding section.

• Perform only the performance verification tests indicated in the

following tables with the letter Q.

If the instrument fails the quick performance check, adjustment or repair
is required

34405A User’s and Service Guide 69

4 Performance Tests and Calibration

NOTE

Performance Verification Tests

The performance verification tests are recommended as acceptance tests
when you first receive the instrument. The acceptance test results should
be compared against the 1- year test limits. After acceptance, you should
repeat the performance verification tests at every calibration interval.

If the instrument fails performance verification, adjustment or repair is
required.

Adjustment is recommended at every calibration interval. If adjustment is
not made, you must establish a 'guard band', using no more than 80% of
the specifications, as the verification limits.

Make sure you have read “Test Considerations” on page 67 before doing the performance
verification tests.

70 34405A User’s and Service Guide

Performance Tests and Calibration 4

NOTE

Zero Offset Verification

This test is used to check the zero offset performance of the instrument.
Verification checks are only performed for those functions and ranges with
unique offset calibration constants. Measurements are checked for each
function and range as described in the procedure on the next page.

Zero Offset Verification Test

1 Connect the Shorting Plug to the HI and LO input terminals. (see “Input

Connections” on page 67). Leave the current inputs open.

2 Select each function and range in the order shown in the table below.

Make a measurement and observe the result. Compare measurement
results to the appropriate test limits shown in the table below (table
continued on thefollowing page).

Note that resistance measurements use the Null math function (Null reading taken with
test leads connected together) to eliminate test lead resistance.

Tab l e 4 Zero Offset Verification Test

Input Function

Open DC Current 10mA Q ±1.5µA

Open 100mA ±5 µA

Open 1A ±70µA

Open 10A ±0.7mA

Open Capacitance 1nF ±8pF

Open 10nF ±0.05nF

Open 100nF ±0.5nF

Open 1µF ±5nF

Open 10µF ±0.05µF

Open 100µF ±0.5µF

[1]

Range Quick Check

Error from Nominal
1 year

34405A User’s and Service Guide 71

4 Performance Tests and Calibration

Tab l e 4 Zero Offset Verification Test

Input Function

Open 1000µF ±5µF

Open 10000µF ±0.05mF

Short DC Volts 100mV ±8 µV

Short 1 V Q ±60 µV

Short 10 V ±0.5 mV

Short 100 V ±5 mV

Short 1000 V ±50 mV

Short 2-Wire Ohms 100 Ω ±8 mΩ [2]

Short 1 kΩ ±50 mΩ [2]

Short 10 kΩ Q ±600 mΩ [2]

Short 100 kΩ ±7 Ω

Short 1 MΩ ±70 Ω

Short 10 MΩ ±500 Ω

Short 100 MΩ ±5 kΩ

[1]

Range Quick Check

Error from Nominal
1 year

[1] Select 5½- digit measurement resolution

[2] Specifications are for 2- wire ohms function using the Null math function enabled
to eliminate lead resistance. Without Null, add 0.2 Ω additional error.

Q = Quick performance verification test points

72 34405A User’s and Service Guide

Gain Verification

This test checks the full- scale reading accuracy of the instrument.
Verification checks are performed only for those functions and ranges with
unique gain calibration constants.

DC Voltage Gain Verification Test

1 Connect the calibrator to the front panel HI and LO input terminals.

2 Select each function and range in the order shown below. Provide the

input shown in the table below.

3 Make a measurement and observe the result. Compare measurement

results to the appropriate test limits shown in the table. (Be certain to
allow for appropriate source settling when using the Fluke 5520A.)

Tab l e 5 DC Voltage Gain Verification Test

Performance Tests and Calibration 4

Input Function

100mV DC Volts 100mV ±33 µV

-100mV 100mV ±33 µV

1V 1 V Q ±0.31 mV

-1V 1 V ±0.31 mV

10V 10 V ±3.0 mV

100V 100 V Q ±30 mV

1000V 1000 V ±0.3 V

Caution: Set the calibrator output to 0V before disconnecting it from the multimeter input terminals.

[1]

[1] Select 5½- digit measurement resolution

Q = Quick performance verification test points

Range Quick Check

Error from Nominal
1 year

34405A User’s and Service Guide 73

4 Performance Tests and Calibration

DC Current Gain Verification Test

1 Connect the calibrator to the front panel I and LO input connectors.

2 Select each function and range in the order shown below. Provide the

input shown in the table below.

3 Make a measurement and observe the result. Compare measurement

results to the appropriate test limits shown in the table. (Be certain to
allow for appropriate source settling when using the Fluke 5520A.)

Tab l e 6 DC Current Gain Verification Test

Input Function

10mA DC Current 10 mA Q ± 6.5µA

100mA 100 mA ± 55µA

1A 1 A Q ± 2.07mA

Caution: Connect calibrator to multimeter’s 12A and LO terminals before applying 10A

10A 10 A ± 25.7mA

[1] Select 5½- digit measurement resolution

Q = Quick performance verification test points

[1]

Range Quick Check

Error from Nominal
1 year

74 34405A User’s and Service Guide

Performance Tests and Calibration 4

Ohms Gain Verification Test

Configuration: 2- Wire Ohms (CONFigure:RESistance)

1 Select the Ohms function.

2 Select each range in the order shown below. Provide the resistance

value indicated. Compare measurement results to the appropriate test
limits shown in the table. (Be certain to allow for appropriate source
settling.)

Tab l e 7 Ohms Gain Verification Test

Input Function

100 Ω 2-Wire Ohms 100 Ω ±58 mΩ [2]

1 kΩ 1 kΩ Q ±550 mΩ [2]

10 kΩ 10 kΩ ±5.6 Ω [2]

100 kΩ 100 kΩ ±57 Ω

1 MΩ 1 MΩ ±670 Ω

10 MΩ 10 MΩ Q ±25.5 kΩ

100 MΩ 100 MΩ ±2.005MΩ

[1] Select 5½- digit measurement resolution

[[2] Specifications are for 2- wire ohms function using the Null math function
enabled to eliminate lead resistance. Without Null, add 0.2 Ω additional error.

Q = Quick performance verification test points

[1]

Range Quick Check

Error from Nominal
1 year

34405A User’s and Service Guide 75

4 Performance Tests and Calibration

Frequency Gain Verification Test

Configuration: Frequency (CONFigure:FREQuency)

1 Select the Frequency function.

2 Select each range in the order shown below. Provide the input voltage

and frequency indicated. Compare measurement results to the
appropriate test limits shown in the table. (Be certain to allow for
appropriate source settling.)

Tab l e 8 Frequency Gain Verification Test

Input

Voltage

200mVrms 1kHz Frequency 1V Q ±0.23Hz

200mVrms 10kHz 1V ±2.3Hz

[1] Select 5½- digit measurement resolution

Q = Quick performance verification test points

Frequency Function

[1]

Range Quick Check

Error from Nominal
1 year

76 34405A User’s and Service Guide

AC Voltage Verification Test

Configuration: AC Volts (CONFigure[:VOLTage]:AC)

1 Select the AC Voltage function.

2 Select each range in the order shown below. Provide the indicated input

voltage and frequency. Compare measurement results to the appropriate
test limits shown in the table. (Be certain to allow for appropriate
source settling.)

Tab l e 9 AC Volts Verification Test

Performance Tests and Calibration 4

Vrms Input Frequency Function

100mV 1kHz AC Voltage 100mV ± 0.3 mV

100mV 30kHz 100mV ± 1.8 mV

100mV 100kHz 100mV ± 5.3 mV

1V 1kHz 1V Q ± 3.0 mV

1V 30kHz 1V ± 11 mV

1V 100kHz 1V ± 32 mV

10V 45Hz 10V ± 110 mV

10V 1kHz 10V ± 30 mV

10V 30kHz 10V Q ± 0.11 V

10V 100kHz 10V ± 0.32 V

100V 1kHz 100V Q ± 0.3 V

100V 30kHz 100V ± 1.1 V

100V 100kHz 100V ± 3.2 V

750V 1kHz 750V ± 2.25 V

Caution: Set the calibrator output to 0V before disconnecting it from the multimeter input terminals.

[1]

Range Quick Check

Error from Nominal
1 year

[1] Select 5½- digit measurement resolution

Q = Quick performance verification test points

34405A User’s and Service Guide 77

4 Performance Tests and Calibration

AC Current Verification Test

Configuration: AC Current (CONFigure:CURRent:AC)

1 Select the AC Current function.

2 Select each range in the order shown below. Provide the input current

and frequency indicated. Compare measurement results to the
appropriate test limits shown in the table. (Be certain to allow for
appropriate source settling.)

Tab l e 10 AC Current Verification Test

Current Input Frequency Function

10 mA 1 kHz AC Current 10 mA Q ± 60 µA

10 mA 10 kHz 10 mA ± 220 µA

100 mA 1 kHz 100 mA ± 600 µA

100 mA 10 kHz 100 mA ± 2.2 mA

1 A 1 kHz 1 A ± 6 mA

1 A 5 kHz 1 A ± 22 mA

Caution: Connect calibrator to multimeter’s 12A and LO terminals before applying 10A

10 A 1 kHz 10 A ± 60 mA

2 A 5 kHz 10 A ± 0.06 A

[1] Select 5½- digit measurement resolution

Q = Quick performance verification test points

[1]

Range Quick Check

Error from Nominal
1 year

78 34405A User’s and Service Guide

Performance Tests and Calibration 4

Optional AC Voltage Performance Verification Test

Configuration: AC Volts (CONFigure[:VOLTage]:AC)

1 Select the AC Voltage function.

2 Select each range in the order shown below. Provide the indicated input

voltage and frequency. Compare measurement results to the appropriate
test limits shown in the table. (Be certain to allow for appropriate
source settling.)

Tab l e 11 Optional AC Voltage Performance Verification Test

Vrms Input Frequency Function

1V 45Hz AC Voltage 1V ±11mV

1V 1kHz 1V ±3mV

1V 10kHz 1V ±3mV

1V 30kHz 1V ±11mV

1V 100kHz 1V ±32mV

10V 1kHz 10V ±30mV

1V 1kHz 10V ±12mV

0.1V 1kHz 10V ±10.2mV

[1] Select 5½- digit measurement resolution

[1]

Range

Error from Nominal
1 year

34405A User’s and Service Guide 79

4 Performance Tests and Calibration

Optional AC Current Performance Verification Test

Configuration: AC Current (CONFigure:CURRent:AC)

1 Select the AC Current function.

2 Select each range in the order shown below. Provide the indicated input

voltage and frequency. Compare measurement results to the appropriate
test limits shown in the table. (Be certain to allow for appropriate
source settling.)

Tab l e 12 Optional AC Current Performance Verification Test

Current Input Frequency Function

10mA 20Hz AC Current 10mA ± 0.16mA

10mA 45Hz 10mA ± 0.16mA

10mA 1kHz 10mA ± 60µA

10mA 10kHz 10mA ± 0.22mA

1A 1kHz 1A ± 6mA

100mA 1kHz 1A ± 1.5mA

10mA 1kHz 1A ± 1.05mA

[1] Select 5½- digit measurement resolution

[1]

Range

Error from Nominal
1 year

80 34405A User’s and Service Guide

Performance Tests and Calibration 4

Optional Capacitance Performance Verification Test

Configuration: Capacitance (CONFigure:CAPacitance)

1 Select the Capacitance function.

2 Select each range in the order shown below. Provide the indicated input

voltage and frequency. Compare measurement results to the appropriate
test limits shown in the table. (Be certain to allow for appropriate
source settling.)

Tab l e 13 Optional Capacitance Performance Verification Test

Error from Nominal

Input Capacitance Range Function

1nF 1nF Capacitance ± 28pF

10nF 10nF ± 0.15nF

100nF 100nF ± 1.5nF

1µF 1µF ± 15nF

[1]

1 year

10µF 10µF ± 0.15µF

100µF 100µF ± 1.5µF

1000µF 1000µF ± 15µF

10000µF 10000µF ± 0.25mF

[1] For the best accuracy, take a zero null measurement with open test leads, to null
out the test lead capacitance, before connecting the test leads to the calibrator.

34405A User’s and Service Guide 81

4 Performance Tests and Calibration

NOTE

Calibration Security

The calibration security code prevents accidental or unauthorized
adjustments to the instrument. When you first receive your instrument, it
is secured. Before you can adjust the instrument, you must unsecure it by
entering the correct security code (see “Unsecuring the Instrument for

Calibration” on page 83).

The security code is set to AT34405 when the instrument is shipped from
the factory. The security code is stored in non- volatile memory, and does
not change when power is turned off or after a Factory Reset (*RST
command) or after an Instrument Preset (SYSTem:PRESet command).

You can unsecure the instrument from the front panel, but you cannot enter a new security
code or change the security code from the front panel. The security code can only be
changed from the remote interface after the instrument has been unsecured. Refer to the
CAL:SEC:CODE command in the 34405A Programmer's Reference Help File for more details.

The security code may contain up to 12 alphanumeric characters. The first
character must be a letter. The remaining characters can be letters or
numbers. You do not have to use all 12 characters.

82 34405A User’s and Service Guide

Performance Tests and Calibration 4

Unsecuring the Instrument for Calibration

Before you can adjust the instrument, you must unsecure it by entering
the correct security code. The security code is set to AT34405 when the
instrument is shipped from the factory. The security code is stored in
non- volatile memory, and does not change when power has been off or
after a Factory Reset (*RST command).

Unsecuring from the Front Panel

Only five characters (the third through seventh characters) of the security
code are used to unsecure the instrument from the front panel. If there
are letters instead of digits in any of the third through seventh characters,
those letters will be represented as "0" from the front panel.

Example 1

Assume the calibration security code is the factory setting of AT34405.
When unsecuring from the front panel, the code length is five characters
and the first two characters are ignored. In our example, the code now
becomes:

34405

Example 2

Assume the calibration security code was set to AT01A405 from the
remote interface. When unsecuring from the front panel, the first two
characters and any characters after the eighth through twelfth character
are ignored. In our example, the code now becomes:

01A40

From the front panel, any letters (A in this example) are represented by 0.
Use this code to unsecure:

01040

34405A User’s and Service Guide 83

4 Performance Tests and Calibration

Shift

DCV

Store

Recall

Store

Recall

Limit

Edit

Range

Disp

Enter

Example 3

Assume the calibration security code has been set to ATB1 through remote
interface. The first two characters (AT) are ignored. The B is represented
by a zero. The “1” is still used and trailing zeros fill in the remaining
characters. Use this code to unsecure:

01000

To U n s e cu re t h e In st r um ent from the Front Panel

1 Press and simultaneously to enter the Calibration

Security Code entry mode.

2 The primary display shows SECur and the secondary display shows _ _

_ _ .

3 Use the editing keys to step to each character

in the code.

Use the range keys to select each character.

4 Press (Enter) when done.

5 If the correct security code was entered, the CAL annunciator

illuminates and the primary display briefly shows PASS.

84 34405A User’s and Service Guide

Calibration Process

NOTE

The following general procedure is the recommended method to complete
a full instrument calibration.

1 Read “Test Considerations” on page 67.

2 Perform the verification tests to characterize the instrument (incoming

data).

3 Unsecure the instrument for calibration (see “Calibration Security” on

page 82). Once unsecured, the instrument will be in Adjustment Mode

as indicated by the illuminated CAL annunciator.

4 Perform the adjustment procedures (see “Adjustments” on page 88).

5 Secure the instrument against calibration.

6 Note the new security code and calibration count in the instrument's

maintenance records.

Make sure to quit the Adjustment Mode then turn off the instrument.

Performance Tests and Calibration 4

34405A User’s and Service Guide 85

4 Performance Tests and Calibration

Store

Recall

Store

Recall

Limit

Edit

Disp

Enter

Shift

Using the Front Panel for Adjustments

This section describes the process used to perform adjustments from the
front panel. Refer to the 34405A Programmer's Reference online help for
remote interface commands.

Selecting the Adjustment Mode

Unsecure the instrument see “Unsecuring the Instrument for Calibration”

on page 83. Once unsecured, the display CAL annunciator illuminates to

indicate you are in Adjustment Mode.

Entering Adjustment Values

In the DMM adjustment procedures, to enter an input calibration value
from the front panel:

Use the edit keys to select each digit in the Secondary
display.

Use the up and down arrow keys to advance through the
digits 0 through 9.

Press when done.

Aborting a Calibration in Progress

Sometimes it may be necessary to abort a calibration after the procedure
has already been initiated. You can abort a calibration at any time by
pressing:

The calibration will be aborted, the primary display will show FAIL and
Error 705, CAL Aborted will occur.

86 34405A User’s and Service Guide

Performance Tests and Calibration 4

CAUTION

If you abort a calibration in progress when the instrument is attempting
to write new calibration constants to EEPROM, you may lose all
calibration constants for the function. Typically, upon re–applying power,
the instrument will report error 742 through 748 (whichever is applicable).
If this occurs, you should not use the instrument until a complete
re–adjustment has been performed. A list of the possible calibration errors
is given on page 103.

34405A User’s and Service Guide 87

4 Performance Tests and Calibration

NOTE

CAUTION

NOTE

Adjustments

You will need a test input cable and connectors set, and a Shorting Plug
to adjust the instrument (see “Input Connections” on page 67).

After each adjustment finishes successfully, the primary display briefly shows PA S S . If the
calibration fails, the multimeter beeps, the primary display shows FAil and an error number
is shown in the secondary display. Calibration error messages are described on page 103. In
the event of a calibration failure, correct the problem and repeat the procedure.

Zero Adjustment

Each time you perform a zero adjustment, the instrument stores a new set
of offset correction constants for measurement functions and ranges. The
instrument will sequence through all required functions and ranges
automatically and store new zero offset calibration constants.

88 34405A User’s and Service Guide

Never turn off the instrument during Zero Adjustment. This may cause ALL calibration
memory to be lost.

Zero Adjustment Procedure

Be sure to allow the instrument to warm up and stabilize for 2 hours
before performing the adjustments.

1 Follow the steps outlined below. Review “Test Considerations” on

page 67 before beginning this test.

2 After unsecuring the instrument, the instrument goes into the

Adjustment Mode (as indicated by the CAL annunciator) with the
secondary display showing Short. Connect the Shorting Plug (see

page 68) between the HI and LO front panel input terminals. Leave the

current inputs open.

To minimize thermal effects wait at least 1 minute after connecting the Shorting Plug before
executing the zero adjustment.

Performance Tests and Calibration 4

dB

Null

Null

Shift

Shift

Hold

Limit

3 Press , the display CAL annunciator starts flashing to

indicate the calibration is in progress.

4 The display will show the measurement functions and ranges as the

adjustments progress.

• Successful completion of the adjustment is indicated by a short beep

and the primary display briefly showing PASS.

• An adjustment failure is indicated by a long beep, the primary

display showing FAiL and a calibration error number appearing in
the secondary display. Correct the problem and repeat this
procedure.

5 Remove the Shorting Plug from the input terminals.

6 Press , the display CAL annunciator will start flashing.

7 The display will show the functions as the open input adjustments

progress.

• Successful completion of the adjustment is indicated by a short beep

and the primary display briefly showing PASS.

• An adjustment failure is indicated by a long beep, the primary

display showing FAiL and a calibration error number appearing in
the secondary display. Correct the problem and repeat this
procedure.

8 Perform the “Zero Offset Verification” on page 71 to check zero

calibration results.

Gain Adjustments

The instrument calculates and stores gain corrections for each input value.
The gain constant is computed from the calibration value entered for the
calibration command and from measurements made automatically during
the adjustment procedure.

Most measuring functions and ranges have gain adjustment procedures.
The 100 M

Adjustments for each function should be performed ONLY in the order
shown.

34405A User’s and Service Guide 89

Ω range does not have gain calibration procedures.

4 Performance Tests and Calibration

CAUTION

Gain Adjustment Considerations

• The zero adjustment procedure must have been recently performed

prior to beginning any gain adjustment procedures.

• Be sure to allow the instrument to warm up and stabilize for 2 hours

before performing the adjustments.

• Consider the thermal effects as you are connecting test leads to the

calibrator and multimeter. It is recommended to wait one minute before
starting the calibration after connecting the test leads.

Never turn off the instrument during a Gain Adjustment. This may cause calibration
memory for the present function to be lost.

Valid Gain Adjustment Input Values Gain adjustment can be accomplished

using the following input values.

Tab l e 14 Valid Gain Adjustment Input Values

Function Range Valid Amplitude Input Values

DC Volts 100 mV, 1 V, 10 V, 100 V, 1000 V 0.9 to 1.1 x Full Scale

DC Current 10 mA, 100 mA, 1000 mA, 10 A 0.9 to 1.1 x Full Scale

Ohms 100 Ω, 1 kΩ, 10 kΩ, 100 kΩ, 1MΩ, 10 M Ω0.9 to 1.1 x Full Scale

Frequency Autorange/1 kHz Input

AC Current 1 mA, 10 mA, 100 mA, 1000 mA, 10 A 0.9 to 1.1 x Full Scale

AC Volts 10 mV, 100 mV, 1 V, 10 V, 100 V, 750 V 0.9 to 1.1 x Full Scale

Capacitance 0.4 nF, 1 nF, 10 nF, 100 nF, 1 µF, 10 µF,

100 µF, 1000 µF, 10000 µF

≥ 100 mV rms, 900 Hz to 1100 Hz

0.9 to 1.1 x Full Scale

90 34405A User’s and Service Guide

Performance Tests and Calibration 4

DCV

NOTE

NOTE

Disp

DC Voltage Gain Adjustment Procedure

Review the “Test Considerations” on page 67 and “Gain Adjustment

Considerations” on page 90 sections before beginning this procedure.

1 Press to enter DC Voltage Gain Calibration.

2 The primary display will show the uncalibrated value and the

secondary display will show the reference value of the Cal Item.

3 Configure each Cal Item shown in the adjustment table below.

If the zero adjustment procedure has been recently performed prior to the DC Voltage gain
calibration procedure, the Cal Item 'Short' can be neglected.

4 Use (Auto) or (Range) to select the Cal Item.

5 Apply the input signal shown in the "Input" column of the table.

Always complete tests in the same order as shown in the appropriate table.

6 Enter the actual applied input (see “Entering Adjustment Values” on

page 86).

7 Press to start the adjustment. The CAL annunciator flashes to

indicate the calibration is in progress.

• Successful completion of each adjustment value is indicated by a

short beep and the primary display briefly showing PASS.

• An adjustment failure is indicated by a long beep, the primary

display showing FAiL and a calibration error number appearing in
the secondary display. Check the input value, range, function, and
entered adjustment value to correct the problem and repeat the
adjustment step.

8 Repeat steps 3 through 7 for each gain adjustment point shown in the

table.

34405A User’s and Service Guide 91

4 Performance Tests and Calibration

DCI

NOTE

9 Ve r ify the DC Volt age G a i n adjustmen t s u sing the “DC Voltage Gain

Verification Test” on page 73.

Tab l e 15 DC Voltage Gain Adjustment

Input Function Cal Item

Dual Banana Plug with copper wire short between 2 terminals DC Voltage Short

100 mV 100 mV

+ 1 V + 1 V

- 1 V - 1 V

10 V 10 V

100 V 100 V

1000 V 1000 V

Caution: Set the calibrator output to 0V before disconnecting from the multimeter input
terminals.

DC Current Gain Adjustment Procedure

Review the “Test Considerations” on page 67 and “Gain Adjustment

Considerations” on page 90 sections before beginning this procedure.

1 Press to enter DC Current Gain Calibration.

2 The primary display will show the uncalibrated value and the

secondary display will show the reference value of Cal Item.

3 Configure each Cal Item shown in the adjustment table below.

If the zero adjustment procedure has been recently performed prior to the DC Current gain
calibration procedure, the Cal Item 'Open' can be neglected.

4 Use (Auto) or (Range) to select the Cal Item.

5 Apply the input signal shown in the "Input" column of the table.

92 34405A User’s and Service Guide

Performance Tests and Calibration 4

NOTE

Disp

Always complete tests in the same order as shown in the appropriate table.

6 Enter the actual applied input (see “Entering Adjustment Values” on

page 86).

7 Press to start the adjustment. The CAL annunciator flashes to

indicate the calibration is in progress.

• Successful completion of each adjustment value is indicated by a

short beep and the primary display briefly showing PASS.

• An adjustment failure is indicated by a long beep, the primary

display showing FAiL and a calibration error number appearing in
the secondary display. Check the input value, range, function, and
entered adjustment value to correct the problem and repeat the
adjustment step.

8 Repeat steps 3 through 7 for each gain adjustment point shown in the

table.

9 Verify the DC Current Gain adjustments using the “DC Current Gain

Verification Test” on page 74.

Tab l e 16 DC Current Gain Adjustment

Input Function Cal Item

Remove test leads from Input terminals DC Current Open

10 mA 10 mA

100 mA 100 mA

1000 mA 1000 mA

Caution: Connect calibrator to multimeter’s 12A and LO terminals before applying 10A

10 A 10 A

34405A User’s and Service Guide 93

4 Performance Tests and Calibration

ACV

NOTE

Disp

AC Voltage Gain Adjustment Procedure

Review the “Test Considerations” on page 67 and “Gain Adjustment

Considerations” on page 90 sections before beginning this procedure.

1 Press to enter AC Voltage Gain Calibration.

2 The primary display will show the uncalibrated value and the

secondary display will show the reference value of Cal Item.

3 Configure each Cal Item shown in the adjustment table below.

4 Use (Auto) or (Range) to select the Cal Item.

5 Apply the input signal shown in the Input and Frequency columns of

the table below.

Always complete tests in the same order as shown in the appropriate table.

6 Enter the actual applied input (see “Entering Adjustment Values” on

page 86).

7 Press to start the adjustment. The CAL annunciator flashes to

indicate the calibration is in progress.

• Successful completion of each adjustment value is indicated by a

short beep and the primary display briefly showing PASS.

• An adjustment failure is indicated by a long beep, the primary

display showing FAiL and a calibration error number appearing in
the secondary display. Check the input value, range, function, and
entered adjustment value to correct the problem and repeat the
adjustment step.

8 Repeat steps 3 through 7 for each gain adjustment point shown in the

table.

9 Verify the AC Voltage Gain adjustments using the “AC Voltage

Verification Test” on page 77.

94 34405A User’s and Service Guide

Tab l e 17 AC Voltage Gain Adjustment

ACI

NOTE

Performance Tests and Calibration 4

Input
Vrms Frequency Function

10 mV 1kHz AC Voltage 10 mV

100 mV 1kHz 100 mV

1 V 1kHZ 1 V

10V 1kHz 10 V

100 V 1kHz 100 V

750 V 1kHz 750 V

Caution: Set the calibrator output to 0V before disconnecting from the multimeter input
terminals.

Frequency as 1kHz
Cal Item

AC Current Gain Adjustment Procedure

Review the “Test Considerations” on page 67 and “Gain Adjustment

Considerations” on page 90 sections before beginning this procedure.

1 Press to enter AC Current Gain Calibration.

2 The primary display will show the calibration value and the secondary

display will show the reference value of the Cal Item.

3 Configure each Cal Item shown in the adjustment table below.

4 Use (Auto) or (Range) to select the Cal Item.

5 Apply the input signal shown in the Input and Frequency columns of

the table below.

Always complete tests in the same order as shown in the appropriate table.

34405A User’s and Service Guide 95

4 Performance Tests and Calibration

Disp

6 Enter the actual applied input (see “Entering Adjustment Values” on

page 86).

7 Press to start the adjustment. The CAL annunciator flashes to

indicate the calibration is in progress.

• Successful completion of each adjustment value is indicated by a

short beep and the primary display briefly showing PASS.

• An adjustment failure is indicated by a long beep, the primary

display showing FAiL and a calibration error number appearing in
the secondary display. Check the input value, range, function, and
entered adjustment value to correct the problem and repeat the
adjustment step.

8 Repeat steps 3 through 7 for each gain adjustment point shown in the

table.

9 Verify the AC Current Gain adjustments using the “AC Current

Verification Test” on page 78.

Tab l e 18 AC Current Gain Adjustment

Input
Current Frequency Function

1 mA 1kHz AC Current 1 mA

10 mA 1kHz 10 mA

100 mA 1kHZ 100 mA

1000 mA 1kHz 1000 mA

Caution: Connect calibrator to multimeter’s 12A and LO
terminals before applying the following 1A and 10A

1 A 1kHz 1 A

10 A 1kHz 10 A

Frequency as 1kHz
Cal Item

96 34405A User’s and Service Guide

Performance Tests and Calibration 4

NOTE

NOTE

Disp

Ohms Gain Adjustment Procedure

Review the “Test Considerations” on page 67 and “Gain Adjustment

Considerations” on page 90 sections before beginning this procedure.

This procedure adjusts the gain for the two-wire ohms function. The gain
for the 100 M
a separate adjustment point.

1 Press to enter the Ohms Gain Adjustment Mode.

2 The primary display will show the calibration value and the secondary

display will show the first reference value of the Cal Item (Short).

3 Configure each Cal Item shown in the adjustment table below.

If the zero adjustment procedure has been recently performed prior to the ohms gain
calibration procedure, the Cal Items Short and Open can be skipped.

4 Use (Auto) or (Range) to select the Cal Item.
5 Apply the input signal shown in the Input column of the table.

Ω range is derived from the 10 MΩ range and does not have

Always complete tests in the same order as shown in the appropriate table.

6 Enter the actual applied input (see “Entering Adjustment Values” on

page 86).

7 Press to start the adjustment. The CAL annunciator flashes to

indicate the calibration is in progress.

• Successful completion of each adjustment value is indicated by a

short beep and the primary display briefly showing PASS.

• An adjustment failure is indicated by a long beep, the primary

display showing FAiL and a calibration error number appearing in
the secondary display. Check the input value, range, function, and
entered adjustment value to correct the problem and repeat the
adjustment step.

8 Repeat steps 3 through 7 for each gain adjustment point shown in the

table.

34405A User’s and Service Guide 97

4 Performance Tests and Calibration

Freq

Freq

NOTE

9 Verify the Ohm Gain adjustments using the “Ohms Gain Verification

Test” on page 75.

Tab l e 19 Ohms Gain Adjustment

Input Function Cal Item

Dual Banana Plug with copper wire short between 2 terminals 2 - Wire Ohms Short

Input terminals open (remove any test leads or shorting plugs
from the input terminals)

10 M Ω 10 MΩ

1 M Ω 1 MΩ

100 k Ω 100 k Ω

10 k Ω 10 k Ω

1 k Ω 1 k Ω

100 Ω 100 Ω

Open

Frequency Gain Adjustment Procedure

Review the “Test Considerations” on page 67 and “Gain Adjustment

Considerations” on page 90 sections before beginning this procedure.

1 Press to enter Frequency Gain Calibration.

2 The primary display will show the calibration value and the secondary

display will show the reference value of Cal Item.

3 Configure each Cal Item shown in the adjustment table below.

4 Use (Auto) or (Range) to select the Cal Item.

5 Apply the input signal shown in the Input Voltage and Frequency

column of the table.

Always complete tests in the same order as shown in the appropriate table.

98 34405A User’s and Service Guide