Fluke 28 II Ex User guide

28 II Ex

True-rms Digital Multimeter

Users Manual

November 2011 Rev. 2, 2/22

© 2011-2012 Fluke Corporation. All rights reserved. Specifications are subject to change without notice.
All product names are trademarks of their respective companies.

LIMITED WARRANTY AND LIMITATION OF LIABILITY

This Fluke product will be free from defects in material and workmanship for three years from the date of purchase. This
warranty does not cover fuses, disposable batteries, or damage from accident, neglect, misuse, alteration, contamination, or
abnormal conditions of operation or handling. Resellers are not authorized to extend any other warranty on Fluke’s behalf.
To obtain service during the warranty period, contact your nearest Fluke authorized service center to obtain return
authorization information, then send the product to that Service Center with a description of the problem.

THIS WARRANTY IS YOUR ONLY REMEDY. NO OTHER WARRANTIES, SUCH AS FITNESS FOR A PARTICULAR
PURPOSE, ARE EXPRESSED OR IMPLIED. FLUKE IS NOT LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR
CONSEQUENTIAL DAMAGES OR LOSSES, ARISING FROM ANY CAUSE OR THEORY. Since some states or countries
do not allow the exclusion or limitation of an implied warranty or of incidental or consequential damages, this limitation of
liability may not apply to you.

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

11/99

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

Table of Contents

Title Page

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

How to Contact Fluke ..................................................................................................... 1

Safety Information .......................................................................................................... 2

Ex Safety Information ..................................................................................................... 2

Errors and Load Restrictions .......................................................................................... 6

Features ......................................................................................................................... 7

Automatic Power-Off ................................................................................................. 14

Input Alert™ Feature ................................................................................................. 14

Power-Up Options ..................................................................................................... 15

How to Make Measurements .......................................................................................... 16

AC and DC Voltage Measurements ........................................................................... 16

Zero Input Behavior of True-rms Meters .................................................................... 17

Low-Pass Filter .......................................................................................................... 18

Temperature Measurements ..................................................................................... 19

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Continuity Tests ........................................................................................................ 19

Resistance Measurements ....................................................................................... 21

How to Use Conductance for High Resistance or Leakage Tests ............................ 23

Capacitance Measurements ..................................................................................... 24

Diode Tests ............................................................................................................... 25

AC or DC Current Measurements ............................................................................. 27

Frequency Measurements ........................................................................................ 30

Duty Cycle Measurements ........................................................................................ 32

How to Determine Pulse Width ................................................................................. 33

HiRes Mode ................................................................................................................... 33

MIN MAX Recording Mode ............................................................................................ 34

Smooth Feature (Power Up Option Only) ...................................................................... 34

AutoHOLD Mode ........................................................................................................... 36

Relative Mode ................................................................................................................ 36

Maintenance .................................................................................................................. 37

General Maintenance ................................................................................................ 37

Fuse Test .................................................................................................................. 37

How to Replace the Batteries.................................................................................... 38

How to Replace the Fuses ........................................................................................ 41

Service and Parts .......................................................................................................... 41

General Specifications ................................................................................................... 44

Detailed Specifications .................................................................................................. 46

AC Voltage ................................................................................................................ 46

DC Voltage, Conductance, and Resistance .............................................................. 47

Temperature ............................................................................................................. 48

AC Current ................................................................................................................ 48

DC Current ................................................................................................................ 49

Capacitance .............................................................................................................. 49

Diode ........................................................................................................................ 50

ii

Contents (continued)

Frequency ................................................................................................................. 50

Frequency Counter Sensitivity and Trigger Levels .................................................... 50

Duty Cycle (Vdc and mVdc) ...................................................................................... 51

Input Characteristics .................................................................................................. 51

MIN MAX Recording .................................................................................................. 52

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iv

Introduction

XW Warning

Read “Safety Information” before using the
Product.

The 28 II EX Digital Multimeter (the Product) is a compact
easy to operate measurement tool for electrical and
electronic circuits.

Read the entire Users Manual and the separate
Safety Instructions before you use the Product.

How to Contact Fluke

Fluke Corporation operates worldwide. For local contact
information, go to our website: www.fluke.com

To register your product, view, print, or download the
latest manual or manual supplement, go to our website.

Fluke Corporation

P.O. Box 9090

Everett, WA 98206-9090

[phone]

[e-mail].

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Safety Information

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

Symbols used on the Product and in this manual are
explained in Table 1.

To ensure safe operation of the Product, obey all
instructions and warnings contained in this manual.

Ex Safety Information

Note

Go to www.ecom-ex.com or www.fluke.com to
download the EU Declaration of Conformity and
Ex certificate for this product. You can also order
a copy from Fluke.

This manual contains information and safety regulations
that must be followed for safe, reliable operation of the
Product in hazardous areas under the described
conditions. Failure to follow the information and
instructions can have dangerous consequences, or may
contravene applicable legislation.

Read this manual before you use the Product.

If there is a question (because of translation and/or
printing errors), refer to the English manual.

XW Warning

To prevent electric shock or personal injury
while in Ex-HAZARDOUS areas, follow these
guidelines:

• Do not open the Product while in an

Ex-hazardous area.

• Change the Product’s batteries only

outside Ex-hazardous areas.

• Do not take spare batteries into

Ex-hazardous areas.

• Use only type-approved batteries in the

Product. See item 5.1 in the Safety
Instructions for a list of approved
batteries.

• Different temperature ranges for T

fixed by the type-approved batteries. See
item 5.1 in the Safety Instructions for a
list of approved batteries.

• Do not replace fuses while in an

Ex-hazardous area.

• Use only fuses approved for

Ex-hazardous areas in this Product. See
item 5.3 in the Safety Instructions for a
list of approved fuses.

• Use the Product only when the specified

connection values are met.

amb

are

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True-rms Digital Multimeter

Ex Safety Information

• After each measurement of a non-

intrinsically safe circuit, the Product
must be off for at least 3 minutes before
it is put again into a hazardous area.

• The Product must be completely and

securely fitted in the red holster while it
is in an Ex-hazardous area.

• Use only approved accessories with this

Product in Ex-hazardous areas.

• Do not use the Product in aggressive

acidic or alkaline solutions.

• For applications requiring Group I

equipment, avoid permanent contact of
the Product with oil, hydraulic fluid, or
grease.

• Do not use the Product in zones 0, 20,

21, or 22. Measurements on intrinsically
safe connections that go into these
zones are permitted, if the connection
values are met.

XW Warning

To prevent personal injury in mining
hazardous areas:

• Avoid extreme mechanical burdens. The

Product can withstand impacts with an
energy of seven joules at -20 °C.

• Do not allow the Product to come in

permanent contact with oil, hydraulic
fluid, or grease.

• Do not install the Product in a fixed

installation.

XW Warning

To prevent possible electrical shock, fire, or
personal injury in ALL areas of operation:

• Read all Safety Information before you

use the Product.

• Comply with local and national safety

codes. Use personal protective
equipment (approved rubber gloves, face
protection, and flame-resistant clothes)
to prevent shock and arc blast injury
where hazardous live conductors are
exposed

• See the Ex Safety Instructions for

additional warnings on Product used in
hazardous areas.

• Use the Product only as specified, or the

protection supplied by the Product can
be compromised.

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• Do not use the Product in damp or wet

environments.

• Do not exceed the Measurement

Category (CAT) rating of the lowest rated
individual component of a Product,
probe, or accessory.

• Examine the case before you use the

Product. Look for cracks or missing
plastic. Carefully look at the insulation
around the terminals.

• Do not use test leads if they are

damaged. Examine the test leads for
damaged insulation, exposed metal, or if
the wear indicator shows. Check test
lead continuity.

• Do not work alone.

• Do not touch voltages >30 V ac rms, 42 V

ac peak, or 60 V dc.

• Use only correct measurement category

(CAT), voltage, and amperage rated
probes, test leads, and adapters for the
measurement.

• Remove all probes, test leads, and

accessories that are not necessary for
the measurement.

• Keep fingers behind the finger guards on

the probes.

• Limit operation to the specified

measurement category, voltage, or
amperage ratings.

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True-rms Digital Multimeter

Ex Safety Information

• Measure a known voltage first to make

sure the Product operates correctly.

• Measure for hazardous voltage without

the Low-Pass Filter.

• Do not apply more than the rated

voltage, between the terminals or
between each terminal and earth ground.

• Do not touch the probes to a voltage

source when the test leads are
connected to the current terminals.

• Connect the common test lead before

the live test lead and remove the live test
lead before the common test lead.

• Replace the batteries when the low

battery indicator shows to prevent
incorrect measurements.

• The battery door must be closed and

locked before you operate the Product.

• Do not use the Product if it operates

incorrectly.

• Do not use and disable the Product if it

is damaged.

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WCaution

To prevent possible damage to the Product
or to the equipment under test, follow these
guidelines:

• Disconnect circuit power and discharge

all high-voltage capacitors before testing
resistance, continuity, diodes, or
capacitance.

• Use the proper terminals, function, and

range for all measurements.

• Before measuring current, check the

fuses in the Product. (See Fuse Test.)

Errors and Load Restrictions

If there is a question that the safety or integrity of this
Product is compromised, remove it from operation and
the Ex-hazardous areas immediately. Also, do whatever
is necessary to prevent Product operation by others until
the Product is examined by an ecom certified technician.
It is recommended that you send the Product to the
manufacturer to be examined.

Because the safety and reliability of the Product can be at
risk, do not operate the Product if:

• Visible damage is found in the housing of the
Product.

• The Product has had an excessive load put on it for
which it is not designed.

• The Product was not stored correctly.

• The Product has sustained damage in transit.

• Illegible inscriptions or lettering shows on the

Product.

• A Product malfunction occurs.

• Obvious measurement inaccuracies occur.

• Measurements/simulations are no longer possible

with the Product.

• Permitted tolerances or threshold values were
exceeded.

6

True-rms Digital Multimeter

T

Features

Table 1. Symbols

W

B

F

J

I

b

R

~

WARNING - RISK OF DANGER. Consult user
documentation.

Double Insulated

AC (Alternating Current)

DC (Direct Current)

Earth

Fuse

Battery. Low battery when displayed.

Continuity test or continuity beeper tone.

This product complies with the WEEE Directive marking requirements. The affixed label 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 I, this product is classed as category 9 "Monitoring and Control Instrumentation" product. Do not
dispose of this product as unsorted municipal waste.

X

E

O

P

(

¼

½

¾

WARNING. HAZARDOUS VOLTAGE. Risk of electric shock.

Capacitance

Diode

Conforms to European Union directives.

Conforms to the European Explosive Atmospheres (ATEX)
directive.

Measurement Category II is applicable to test and measuring
circuits connected directly to utilization points (socket outlets
and similar points) of the low-voltage MAINS installation.

Measurement Category III is applicable to test and measuring
circuits connected to the distribution part of the building’s low­voltage MAINS installation.

Measurement Category IV is applicable to test and measuring
circuits connected at the source of the building’s low-voltage
MAINS installation.

Features

Tables 2 through 5 show the features of the Product.

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Users Manual

Table 2. Inputs

Item Terminal Description

A A

B w

C

k

D COM

Input for 0 A to 10.00 A current (10 A to 20 A overload for 30 seconds maximum),
current frequency, and duty cycle measurements.

Input for voltage, continuity, resistance, diode, capacitance, frequency, temperature,
and duty cycle measurements.

Input for 0 μA to 400 mA current measurements (600 mA for 18 hrs) and current
frequency and duty cycle.

Return terminal for all measurements.

grt01.ti

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True-rms Digital Multimeter

Features

Table 3. Rotary Switch Positions

Switch Position

Any Position When the Product is turned on, the Product model number briefly shows on the display.

J

Function

AC voltage measurement

A (yellow) for low-pass filter (K)

Push

L DC voltage measurement

M

N

600 mV dc voltage range

Push A (yellow) for temperature (d)

Push E for continuity test.

e Resistance measurement

Push A (yellow) for capacitance measurement.

O Diode test

P

Q

AC current measurements from 0 mA to 10.00 A

A (yellow) for dc current measurements, from 0 mA to 10.00 A.

Push

AC current measurements from 0 μA to 6000 μA
Push A (yellow) for dc current measurements from 0 μA to 6000 μA.

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Table 4. Pushbuttons

Button

Switch

Position

N

A

(Yellow)

Any

C

position

M

Any
position

D

MIN MAX
recording

Frequency
counter

M

J

P

Q

Function

Set to capacitance

Set to temperature

Turn on ac low-pass filter

Set dc or ac current

Set dc or ac current

Change and set the range for the set function. To go to autoranging, hold the button down for
1 second.

Sets to °C or °F.

AutoHOLD (formerly TouchHold) captures the current measurement on the display. When a
new, stable measurement is sensed, the Product beeps and shows the new measurement.

Stops and starts recording. Does not erase recorded values.

Stops and starts the frequency counter.

10

True-rms Digital Multimeter

Features

Table 4. Pushbuttons (cont.)

Button

E

H

B

F

(Relative

mode)

G

Switch

Position

Continuity
N

MIN MAX
recording

Hz, Duty
Cycle

Any
position

Any
position

Any
position

Any
position
except
diode test

Function

Toggle the continuity beeper on and off.

Switches between Peak (250 μs) and Normal (100 ms) response times.

Toggles the Product to trigger on positive or negative slope.

Turns on the button backlight and display backlight, makes them brighter, and turns off the
backlights. Hold
the display. To go back to the 3-1/2 digit mode, hold

Starts recording of minimum and maximum values. Steps the display through MAX, MIN, AVG
(average), and current measurement. Cancels MIN MAX (hold for 1 second).

Stores the current measurement as a reference for subsequent measurements. The display is
zeroed, and the stored measurement is subtracted from all subsequent measurements.

Push G for frequency measurements.

Push again to go to duty cycle mode.

H down for 1 second to enter the HiRes digit mode. The “HiRes” icon shows in

H down for 1 second. HiRes=19999.

11

28 II Ex

A

Users Manual

Number Feature Indication

Negative measurement. In relative

E

F

G

-

Z

RS

mode, this sign shows that the input
is less than the stored reference.

High voltage present at the input.
Appears if the input voltage is 30 V
or greater (ac or dc). Also shows in
low-pass filter mode. Also shows in
cal, Hz, and duty cycle modes.

AutoHOLD is active.

Figure 1. Display Features

Table 5. Display Features

Number Feature Indication

A

B

C

D

±Trig

X

W

a

Positive or negative slope indicator
for Hz/duty cycle triggering.

The continuity beeper is on.

Relative (REL) mode is active.

Smoothing is active.

grt09.tif

H

I

S

p

€

J

MAX MIN

VG

K

K

Display HOLD is active.

Peak Min Max modes and the
response time is 250 μs.

Minimum-maximum recording mode.

Low-pass filter mode. See “Low­pass Filter”.

12

True-rms Digital Multimeter

Features

Table 5. Display Features (cont.)

Number Feature Indication

Low battery. XW Warning: To

avoid false readings, which

L b

could lead to possible electric
shock or personal injury,
replace the battery as soon as
the battery indicator appears.

amperes (amps), microamp, milliamp

volts, millivolts

microfarad, nanofarad

nanosiemens

Percent. Used for duty cycle
measurements.

ohm, megohm, kilohm

hertz, kilohertz

Diode test mode

Alternating current, direct current

M

A, μA, mA

V, mV

μF, nF

nS

%

Ω, MΩ, kΩ

Hz, kHz

O

AC DC

Number Feature Indication

N °C °F

O 610000 mV

P

Auto

Manual

Q HiRes

Degrees Celsius, Degrees
Fahrenheit

Displays selected range

Autorange mode. Automatically
selects the range with the best
resolution.

Manual range mode

High resolution (Hi Res) mode
HiRes=19999

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Table 5. Display Features (cont.)

Number Feature Indication

--

bAtt

di'c

CAL Err

EEPr Err

0PEn

F2_

LEAd

0L

Replace the battery immediately.

In the capacitance function, too much electrical
charge is on the capacitor under test.

Invalid calibration data. Calibrate Product.

Invalid EEPROM data. Have the Product serviced.

Open thermocouple detected.

Invalid model. Have the Product serviced.

W Test lead alert. Shows when the test leads are in
the

A or mA/μA terminal and the selected rotary

switch position does not correspond to the terminal
being used.

Overload condition is detected.

Error Messages

Automatic Power-Off

The Product automatically turns off if you do not turn the
rotary switch or push a button for 30 minutes. If MIN MAX
Recording mode is on, the Product will not turn off. Refer
to Table 6 to disable automatic power-off.

Input Alert™ Feature

If a test lead is connected to the mA/μA or A terminal, but
the rotary switch is not set to the correct current position,
the beeper warns you by making a chirping sound and
the display flashes “LEAd”. This warning is intended to
stop you from attempting to measure voltage, continuity,
resistance, capacitance, or diode values with the leads
plugged into a current terminal.

W Caution

To prevent damage, do not put the probes
across (in parallel with) a circuit with power
with a lead connected to a current terminal.
This can cause damage to a circuit with
power and blow the Product fuse. This can
occur because the resistance through the
current terminals of the Product is very low
and causes a short circuit.

14

True-rms Digital Multimeter

Features

Power-Up Options

To set a power-up option, push a button from the list in Table 6 as you turn on the Product.

Table 6. Power-Up Options

Button Power-Up Option

A

(Yellow)

B

Disables automatic power-off feature (Product normally powers off in 30 minutes).

The Product reads “PoFF” until A is released.

Sets the Product in calibration mode and prompts for a password.

The Product shows “CAL” in the display and enters calibration mode. See 28 II EX Calibration Information.

C Turns on the smoothing feature. The Product reads “'---” until C is released.

D Turns on all LCD segments.

E Disables the beeper for all functions. The Product reads “bEEP” until E is released.

H

G

Disables auto backlight off (backlight normally disables after 2 minutes). The Product reads “LoFF” until H
is released.

Sets the Product into the high impedance mode when the mV dc function is used.

The Product reads “Hi2” until G is released.

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How to Make Measurements

The Product features true-rms measurements, which are
accurate for distorted sine waves and other waveforms
(with no dc offset) such as square waves, triangle waves,
and staircase waves.

AC and DC Voltage Measurements

The voltage ranges of the Product are 600.0 mV, 6.000 V,

60.00 V, 600.0 V, and 1000 V. To select the 600.0 mV dc
range, turn the rotary switch to l.

Refer to Figure 2 to measure ac or dc voltage.

16

Figure 2. AC and DC Voltage Measurements

grt02.tif

True-rms Digital Multimeter

How to Make Measurements

When you measure voltage, the Product puts
approximately 10-MΩ (10,000,000 Ω) impedance in
parallel with the circuit. This loading effect can cause
measurement errors in high-impedance circuits. In most
cases, the error is negligible (0.1 % or less) if the circuit
impedance is 10 kΩ (10,000 Ω) or less.

For better accuracy when you measure the dc offset of an
ac voltage, measure the ac voltage first. Record the ac
voltage range, then manually select a dc voltage range
equal to or higher than the ac range. This procedure has
better accuracy of the dc measurement because the input
protection circuits are disabled.

Zero Input Behavior of True-rms Meters

True-rms meters accurately measure distorted
waveforms, but when the input leads are shorted together
in the ac functions, the Product shows a measurement
between 1 and 30 counts. When the test leads are open,
the measurements can change from interference. These
offset measurements are common. They do not change
the ac measurement accuracy of the Product for the
specified measurement ranges.

Unspecified input levels are:

• AC voltage: below 3 % of 600 mV ac, or 18 mV ac

• AC current: below 3 % of 60 mA ac, or 1.8 mA ac

• AC current: below 3 % of 600 μA ac, or 18 μA ac

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Low-Pass Filter

The Product has an ac low-pass filter. When you
measure ac voltage or ac frequency, push A to set
the low-pass filter mode (K). The Product measures in
the chosen mode, but the signal diverts through a filter
that stops unwanted voltages more than 1 kHz, refer to
Figure 3. The lower frequency voltages go through with
decreased accuracy to the measurement less than 1 kHz.
The low-pass filter can get you better measurement
performance on composite sine waves that are typically
found on inverters and variable-frequency motor drives.

XW Warning

To prevent electric shock or personal injury,
do not use the low-pass filter when you
measure for hazardous voltages. Voltages
larger than what is shown can be present.
First, make a voltage measurement without
the filter to see if a hazardous voltage is
present. Then, select the filter.

Note

When the low-pass filter is selected, the Product
goes to manual range mode. Push C to set
the range. The Product does not autorange with
the low-pass filter set.

Figure 3. Low-Pass Filter

aom11f.tif

18

True-rms Digital Multimeter

How to Make Measurements

Temperature Measurements

The Product measures the temperature of a type-K
thermocouple. Push C to toggle between degrees
Celsius (°C) or degrees Fahrenheit (°F).

W Caution

To prevent damage to the Product or other
equipment, remember that while the Product
is rated for -200.0 °C to +1090.0 °C (-328.0 °F
to 1994 °F), the type-K thermocouple is rated
to 260 °C. For temperatures out of that range,
use a higher rated thermocouple.

Display ranges are -200.0 °C to +1090 °C and -328.0 °F
to 1994 °F. Measurements outside these ranges show 0L
in the display. When there is no thermocouple connected,
the display also shows 0PEn.

To measure temperature:

1. Connect a type-K thermocouple to the COM and w

terminals of the Product.

2. Turn the rotary switch to M.

3. Push A to enter temperature mode.

4. Push C to choose Celsius or Fahrenheit.

Continuity Tests

WCaution

To prevent damage to the Product or to the
equipment under test, disconnect circuit
power and discharge all high-voltage
capacitors before you do a continuity test.

The continuity test has a beeper that sounds when a
circuit is complete. You can do continuity tests and not
have to look at the display.

To do a continuity test, set up the Product as shown in
Figure 4.

Push E to turn on or turn off the continuity beeper.

The continuity function senses intermittent opens and
shorts that last as little as 1 ms. A brief short causes the
Product to emit a short beep.

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20

Figure 4. Continuity Tests

grt03.tif

True-rms Digital Multimeter

How to Make Measurements

Resistance Measurements

WCaution

To prevent damage to the Product or to the
equipment under test, disconnect the power
and discharge all high-voltage capacitors
before you measure resistance.

The Product sends a small current through the circuit to
measure resistance. Because this current flows through
all possible paths between the probes, the resistance
measurement shows the total resistance of all paths
between the probes.

The resistance ranges of the Product are 600.0 Ω,

6.000 kΩ, 60.00 kΩ, 600.0 kΩ, 6.000 MΩ, and 50.00 MΩ.

Connect the Product to the circuit as shown in Figure 5 to
measure resistance.

Some guidelines for resistance measurements are:

• The measured value of a resistor in a circuit can be
different from the resistor's rated value.

• The test leads can add 0.1 Ω to 0.2 Ω of error to
resistance measurements. To test the leads, touch
the probe tips together and read the resistance of the
leads. If necessary, you can use the relative (REL)
mode to automatically subtract this value.

• The resistance function can output a voltage that
causes a forward-bias silicon diode or transistor
junction to conduct. If this occurs, push C to
apply a lower current in the next higher range. If the
value is higher, use the higher value. Refer to the
Input Characteristics table in the specifications
section for typical short-circuit currents.

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22

Figure 5. Resistance Measurements

grt04.tif

True-rms Digital Multimeter

How to Make Measurements

How to Use Conductance for High Resistance or
Leakage Tests

Conductance, the inverse of resistance, is a measure of
how easily current goes through a circuit. High values of
conductance are the same as low values of resistance.

The 60-nS range of the Product measures conductance
in nanosiemens (1 nS = 0.000000001 siemens). Because
such small quantities of conductance are equal to very
high resistance, the nS range lets you measure the
resistance of components with a maximum of
100,000 MΩ, 1/1 nS = 1,000 MΩ.

To measure conductance, set up the Product for
resistance measurement as shown in Figure 5, then push
C until the nS indicator shows in the display.

Some guidelines for conductance measurements are:

• High-resistance measurements are susceptible to

electrical noise. To smooth out most noisy
measurements, start the MIN MAX recording mode;
then step to the average (AVG) reading.

• It is usual to have a conductance measurement in

the display with the test leads open. To make sure
you make accurate measurements, use the relative
(REL) mode to subtract this open measurement
value.

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Capacitance Measurements

WCaution

To prevent damage to the Product or to the
equipment under test, disconnect circuit
power and discharge all high-voltage
capacitors before you measure capacitance.
Use the dc voltage function to make sure that
the capacitor is discharged.

The capacitance ranges of the Product are 10.00 nF,

100.0 nF, 1.000 μF, 10.00 μF, 100.0 μF, and 9999 μF.

To measure capacitance, set up the Product as shown in
Figure 6.

For the best capacitance measurement accuracy on
capacitance less than 1000 nF, use the relative (REL)
mode to subtract the remaining capacitance of the
Product and leads.

Note

When a capacitor under test has too much
electrical charge, the display shows “diSC“.

24

Figure 6. Capacitance Measurements

grt05.tif

True-rms Digital Multimeter

How to Make Measurements

Diode Tests

WCaution

To prevent damage to the Product or to the
equipment under test, disconnect circuit
power and discharge all high-voltage
capacitors before you do a diode test.

Use the diode test to examine diodes, transistors, silicon
controlled rectifiers (SCRs), and other semiconductor
devices. This test sends current through a semiconductor
junction, while it measures the junction's voltage drop. A
good silicon junction drops between 0.5 V and 0.8 V.

To do an out-of-circuit diode test, set up the Product as
shown in Figure 7. For forward-bias measurements on a
semiconductor component, put the red test lead on the
component's positive terminal and put the black lead on
the component's negative terminal.

In a circuit, a good diode will cause a forward-bias
measurement of 0.5 V to 0.8 V. A reverse-bias
measurement can be different because of the resistance
of other pathways between the probe tips.

A short beep sounds if the diode is good (<0.85 V). A
continuous beep sounds if the measurement is ≤0.100 V.
This measurement shows a short circuit. The display
shows “OL” if the diode is open.

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26

Figure 7. Diode Tests

grt06.tif

True-rms Digital Multimeter

How to Make Measurements

AC or DC Current Measurements

XWWarning

To prevent electric shock or personal injury,
do not try an in-circuit current measurement
where the open-circuit potential to earth is
larger than 1000 V. You can cause Product
damage or personal injury if the fuse blows.

WCaution

To prevent damage to the Product or to the
equipment under test:

• Examine the fuses of the Product before

you measure current.

• Use the correct terminals, function, and

range for all measurements.

• Do not put the probes across (in parallel

with) a circuit or component when the
leads are connected to the current
terminals.

To measure current, you must open the current path of
the circuit under test and put the Product in series with
the circuit.

The current ranges of the Product are 600.0 μA, 6000 μA,

60.00 mA, 400.0 mA, 6.000 A, and 10.00 A.

To measure current, refer to Figure 8 and continue as
follows:

1. Remove power from the circuit. Discharge all high­voltage capacitors.

2. Put the black lead into the COM terminal. For
currents between 0 mA and 400 mA, put the red lead
into the mA/μA terminal. For currents more than
400 mA, put the red lead into the A terminal.

Note

To prevent damage to the 400-mA fuse of the Product,
use the mA/
less than 400 mA continuously or less than 600 mA for
18 hours or less.

μ

A terminal only if you are sure the current is

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28

Figure 8. Current Measurements

grt07.tif

True-rms Digital Multimeter

How to Make Measurements

3. If you use the A terminal, set the rotary switch to
mA/A. If you use the mA/μA terminal, set the rotary
switch to Q for currents below 6000 μA (6 mA), or
P for currents above 6000 μA.

4. To measure dc current, push A.

5. Open the test circuit path. Touch the black probe to
the more negative side of the break. Touch the red
probe to the more positive side of the break. If the
leads are reversed, the measurement will be
negative, but will not cause Product damage.

6. Apply power to the circuit and then read the display.
Be sure to note the unit given at the right side of the
display (μA, mA, or A).

7. Remove power from the circuit and discharge all
high-voltage capacitors. Remove the Product and
restore the circuit to normal operation.

Some guidelines for current measurements are:

• If the current measurement is 0 A and you are sure
the Product is set up correctly, do a fuse test. See
the "Fuse Test" section.

• A current meter drops a small voltage across itself,
which could change circuit operation. You can
calculate this burden voltage with the values shown
in the specifications.

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Frequency Measurements

For frequency measurements, the Product counts the
number of times the signal crosses a set voltage level
each second.

Table 7 summarizes the trigger levels and applications for
frequency measurements in the ranges of the voltage and
current functions of the Product.

To measure frequency, connect the Product to the signal
source. Next, push
trigger slope switches between + and -, as shown by the
symbol at the left side of the display (refer to Figure 9
under "Duty Cycle"). Push
counter.

The Product autoranges to one of five frequency ranges:

199.99 Hz, 1999.9 Hz, 19.999 kHz, 199.99 kHz, and
>200 kHz. For frequencies less than 10 Hz, the display is
updated at the frequency of the input. Less than 0.5 Hz,
the display can be unstable.

G. When you push E, the

D to stop and start the

Some guidelines for frequency measurements are:

• If a measurement shows as 0 Hz or is unstable, the
input signal can be below or near the trigger level. To
correct these problems, go to a lower range, which
increases the sensitivity of the Product. In the L
function, the lower ranges also have lower trigger
levels.

• If a measurement is a multiple of what you expect,
the input signal can be distorted. Distortion can
cause multiple triggers of the frequency counter.
Select a higher voltage range to decrease Product
sensitivity and try to repair this problem. You can
also set a dc range to increase the trigger level as a
possible solution. In general, the lowest frequency
shown in the display is the correct one.

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True-rms Digital Multimeter

How to Make Measurements

Table 7. Functions and Trigger Levels for Frequency Measurements

Function Range

v

v

l

V

V

V

V

6 V, 60 V,
600 V, 1000 V

600 mV ±30 mV High-frequency 5 V logic signals. (The dc-coupling of the L function can

600 mV 40 mV Refer to the measurement guidelines given before this table.

6 V 1.7 V 5 V logic signals (TTL).

60 V 4 V Automotive switching signals.

600 V 40 V Refer to the measurement guidelines given before this table.

1000 V 100 V

w

\

μAF

^

All ranges ±5 % of scale AC current signals.

600 μA, 6000 μA 30 μA , 300 μA Refer to the measurement guidelines given before this table.

60 mA, 400 mA 3.0 mA , 30 mA

Approximate

Trigger Level

±5 % of scale Most signals.

Frequency counter characteristics are not available or specified for these functions.

AF 6 A, 10 A 0.30 A, 3.0 A

Typical Application

attenuate high-frequency logic signals, reducing their amplitude enough to
interfere with triggering.)

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Duty Cycle Measurements

Duty cycle (or duty factor) is the percentage of time a
signal is above or below a trigger level in one cycle
(Figure 9). The duty cycle mode is optimized to measure
the on or off time of logic and switching signals. Systems
such as electronic fuel injection systems and switching
power supplies are controlled by pulses that have
different widths, which can be measured by a duty cycle
measurement.

Figure 9. Components of Duty Cycle Measurements

To measure duty cycle, set up the Product to measure
frequency. Then push G a second time. As with the
frequency function, push E to change the slope for
the counter.

For 5-V logic signals, use the 6-V dc range. For 12-V
switching signals in automobiles, use the 60 V dc range.
For sine waves, use the lowest range that does not result
in multiple triggers. (Normally, a distortion-free signal can
be up to 10x the amplitude of the selected voltage range.)

If a duty cycle measurement is unstable, push MIN MAX
and then scroll to the AVG (average) display.

iyf.tif

32

True-rms Digital Multimeter

HiRes Mode

How to Determine Pulse Width

For a periodic waveform (its pattern repeats at equal time
intervals), you can find the time that the signal is high or
low as follows:

1. Measure the signal's frequency.

2. Push G a second time to measure the signal's
duty cycle. Push E to select a measurement of
the signal's positive or negative pulse, refer to
Figure 9.

3. Use this formula to find the pulse width:

Pulse Width
(in seconds) Frequency

% Duty Cycle ÷ 100

=

HiRes Mode

On the Product, push H for one second to enter the high­resolution (HiRes) 4-1/2 digit mode. Measurements are
shown at 10x the usual resolution with a maximum
display of 19999 counts. The HiRes mode works in all
modes but capacitance, frequency counter functions,
temperature, and the 250 μs (peak) MIN MAX modes.

To go to the 3-1/2 digit mode, push H for one second.

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MIN MAX Recording Mode

The MIN MAX mode records minimum and maximum
input values. When the inputs go below the recorded
minimum value or above the recorded maximum value,
the Product beeps and records the new value. This mode
can be used to record intermittent measurements, record
maximum measurements while you are away or record
measurements while you operate the equipment under
test and cannot look at the Product. MIN MAX mode can
also calculate an average of all measurements since the
MIN MAX mode was started. To use MIN MAX mode,
refer to the functions in Table 8.

Response time is the length of time an input must stay at
a new value to be recorded. A shorter response time
records shorter events, but with decreased accuracy. All
recorded measurements are erased when you change
the response time. The Product has 100 millisecond and
250 μs (peak) response times. The 250 μs response time
is indicated by “p” on the display.

The 100 millisecond response time is best for power
supply surges, inrush currents, and intermittents.

The average value (AVG) shown in the display is the
mathematical integral of all measurements since the start
of recording (overloads are discarded). The average
value is useful to smooth out unstable inputs, calculate
power consumption, or to get a percentage of time
estimate on how long a circuit is on.

Min Max records the signal extremes that are longer than
100 ms.

Peak records the signal extremes that are longer than
250 μs.

Smooth Feature (Power Up Option Only)

When the input signal changes quickly, “smoothing” gives
a more stable measurement on the display.

To use the smooth feature:

1. Hold down C while you turn the Product on. The
display shows “'---” until C is released.

2. The Smoothing icon (a) will appear on the left side
of the display to let you know that smoothing is on.

34

True-rms Digital Multimeter

Smooth Feature (Power Up Option Only)

Table 8. MIN MAX Functions

Button MIN MAX Function

Enter MIN MAX recording mode. The Product is locked in the range shown before you

B

started MIN MAX mode. (Set the measurement function and range before you enter MIN
MAX.) The Product beeps each time a new minimum or maximum value is recorded.

B

(while in MIN MAX mode)

E

PEAK MIN MAX

D Stop recording. Stored values are not erased. Push again to continue recording.

B

(hold for 1 second)

Step through maximum (MAX), minimum (MIN), average (AVG) and current values.

Select 100 ms or 250 μs response time. (The 250 μs response time is shown by p
on the display.) Stored values are erased. The current and AVG (average) values are not
available when 250 μs is selected.

Exit MIN MAX mode. Stored values are erased. The Product stays in the selected range.

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AutoHOLD Mode

XWWarning

To prevent electrical shock or personal
injury, do not use AutoHOLD mode to see if
circuits are without power. The AutoHOLD
mode will not hold on unstable or noisy
measurements.

The AutoHOLD mode locks the current measurement on
the display. When a new, stable measurement is sensed,
the Product beeps and shows the new measurement. To
start or exit AutoHOLD mode, push D.

Relative Mode

When you set relative mode (F), the Product zeros
the display and stores the current measurement as the
reference for subsequent measurements. The Product is
locked into the range selected when you push
Push F again to exit this mode.

In relative mode, the measurement shown is always the
difference between the current measurement and the
stored reference value. For example, if the stored
reference value is 15.00 V and the current measurement
is 14.10 V, the display shows -0.90 V.

F.

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True-rms Digital Multimeter

Maintenance

Maintenance

XWWarning

To prevent electrical shock or personal
injury, have the Product repaired by ECOM
Instruments GmbH or an ECOM authorized
service center to keep Product certification.

General Maintenance

To clean the external surfaces of the Product, wipe the
case with a damp cloth and mild detergent. Do not use
abrasives or solvents.

Dirt or moisture in the terminals can cause incorrect
measurements and can falsely set off the Input Alert
feature. Clean the terminals as follows:

1. Turn off the Product and remove all test leads.

2. Shake out dirt that can be in the terminals.

3. Soak a clean swab with mild detergent and water.
Move the swab around in each terminal. Dry each
terminal with canned air to push the water and
detergent out of the terminals.

Fluke recommends calibration for the Product in two-year
intervals by Fluke.

Fuse Test

As shown in Figure 10, with the Product in the N
function, put a test lead into the w jack and place the
probe tip on the other end of the test lead against the
metal of the current input jack. If “LEAd” appears in the
display, the probe tip has been inserted too far into the
amps input jack. Lift the lead out a bit until the message
no longer shows in the display and OL or a resistance
measurement shows in the display. The resistance value
must be as shown in Figure 10. If the tests give
measurements other than those shown, have the Product
serviced.

XWWarning

To prevent electric shock or personal injury,
remove the test leads and all input signals
before you replace the batteries or fuses. To
prevent damage or injury, install ONLY
specified replacement fuses with the
amperage, voltage, and speed ratings shown
in Table 9.

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Figure 10. Current Fuse Test

grt08.tif

How to Replace the Batteries

Replace the batteries with three AAA
batteries (NEDA 24A IEC LR03).

XWWarning

To prevent electrical shock or personal
injury:

• Replace the batteries when the low

battery indicator (b) shows to prevent
incorrect measurements. If the display
shows “batt” the Product will not
function until the batteries are replaced.

• Use only three AAA 1.5-volt batteries,

correctly installed to power the Product.
See item 5.1 in the Safety Instructions for
a list of approved batteries. All batteries
are to be replaced at the same time with
same part number batteries outside the
Ex-hazardous area.

38

True-rms Digital Multimeter

Maintenance

Replace the batteries as follows, refer to Figure 11:

1. Turn the rotary switch to OFF and remove the test
leads from the terminals.

2. Remove the six Torx-head screws from the case
bottom and remove the battery door (A).

Note

When you lift the battery door, make sure the
rubber gasket stays attached to the battery
compartment barrier.

3. Remove the three batteries and replace all three with
AAA Alkaline batteries (B).

4. Make sure the battery compartment gasket (C) is
properly installed around the outside edge of the
battery compartment barrier.

5. Align the battery compartment barrier with battery
compartment while you replace the battery door.

6. Attach the door with the six Torx-head screws.

Note

Fluke recommends that you remove the
batteries from the Product for long periods of
storage.

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40

Figure 11. Battery and Fuse Replacement

grt10.tif

True-rms Digital Multimeter

Service and Parts

How to Replace the Fuses

Examine or replace the fuses in the Product as follows
(See Figure 11):

1. Turn the rotary switch to OFF and remove the test
leads from the terminals

2. Refer to step 2 in How to Replace the Batteries to
remove the battery door.

3. Carefully lift out the fuse assembly (D) from the fuse
compartment.

4. Remove the 11 A fuse by carefully prying one end
loose, then lift the fuse out of its bracket (E).

5. Install ONLY specified replacement fuses with the
amperage, voltage, and speed ratings shown in
Table 9. The 440-mA fuse is attached to the fuse

assembly. You must use a new fuse assembly to
replace the 440 mA fuse.

6. Install the fuse assembly into the fuse compartment.

7. Refer to How to Replace the Batteries to replace the
battery door.

Service and Parts

If the Product fails, examine the batteries and fuses.
Refer to this manual to make sure the Product is used
correctly.

Replacement parts and accessories are shown in Table 9
and Figure 12.

To order parts and accessories, see How to Contact
Fluke.

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Table 9. Replacement Parts

Description Qty. Fluke Part or Model Number

Fuse, 11 A, 1000 V, FAST 1

28 II EX Fuse Assembly 1

Alligator Clip, Black 1

Alligator Clip, Red 1

Test Lead Set 1

28 II EX Getting Started Manual 1

Fluke Input Cap, Amp Jack Plugs for DMMs (10 pack) 1

W To ensure safety, use exact replacement only.

803293

4016494

AC172 or AC175

TL175

3945752

4145825

42

True-rms Digital Multimeter

Service and Parts

Figure 12. Replacement Parts

grt11.tif

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General Specifications

Maximum voltage between any

terminal and earth ground ........................................... 1000 V

W Fuse for mA inputs .................................................. 0.44 A, 1000 V IR 10 kA

W Fuse for A inputs ..................................................... 11 A, 1000 V IR 17 kA

Display ........................................................................... 6000 counts, updates 4/sec (19999 counts in high-resolution mode).

Altitude

Operating .................................................................... 2000 meters

Storage ....................................................................... 10 000 meters

Operating Temperature ................................................ Different temperature ranges for T

separate Safety Instructions for a list of approved batteries)

Temperature coefficient ............................................... 0.05 X (specified accuracy) / °C (<18 °C or >28 °C)

Relative Humidity .......................................................... 0 % to 80 % (0 °C to 35 °C)

0 % to 70 % (35 °C to 50 °C)

Battery Type .................................................................. 3 AAA Alkaline batteries, NEDA 24A IEC LR03 (see separate Safety Instructions for

a list of approved batteries)

Battery Life .................................................................... 400 hr typical without backlight (Alkaline)

Size (H x W x L) ............................................................. 4.57 cm x 10.0 cm x 21.33 cm (1.80 in x 3.95 in x 8.40 in)

Size with Holster ........................................................... 6.35 cm x 10.0 cm x 19.81 cm (2.50 in x 3.95 in x 7.80 in)

Weight ............................................................................ 567.8 g (1.25 lb)

Weight with Holster and Flex-Stand ............................ 769.8 g (1.70 lb)

are fixed by type-approved batteries (see

amb

44

True-rms Digital Multimeter

General Specifications

Safety

General ....................................................................... IEC 61010-1: Pollution Degree 2

Measurement .............................................................. IEC 61010-2-033: CAT IV 600V / CAT III 1000V

Ingress Protection ....................................................... IEC 60529: IP67, non-operating

Electromagnetic Compatibility (EMC) ......................... In an RF field of 3 V/M, accuracy = specified accuracy +20 counts, except 600 μA dc

International ................................................................ IEC 61326-1: Portable Electromagnetic Environment

Korea (KCC) ................................................................ Class A Equipment (Industrial Broadcasting & Communication Equipment)

USA (FCC) .................................................................. 47 CFR 15 subpart B. This product is considered an exempt device per clause

range total accuracy = specified accuracy +60 counts. Temperature not specified

IEC 61326-2-2 CISPR 11: Group 1, Class A

Group 1: Equipment has intentionally generated and/or uses conductively-coupled
radio frequency energy that is necessary for the internal function of the equipment
itself.

Class A: Equipment is suitable for use in all establishments other than domestic
and those directly connected to a low-voltage power supply network that supplies
buildings used for domestic purposes. There may be potential difficulties in
ensuring electromagnetic compatibility in other environments due to conducted
and radiated disturbances.

Caution: This equipment is not intended for use in residential environments and
may not provide adequate protection to radio reception in such environments.

Class A: Equipment meets requirements for industrial electromagnetic wave
equipment and the seller or user should take notice of it. This equipment is
intended for use in business environments and not to be used in homes.

15.103.

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Detailed Specifications

For all detailed specifications:

Accuracy is specified for 2 years after calibration, at operating temperatures of 18 °C to 28 °C, with relative humidity at 0 % to 80 %.
Accuracy specifications take the form of ±([% of Reading] + [Number of least-significant digits]). In the 4 ½-digit mode, multiply the number of
least-significant digits (counts) by 10.

AC Voltage

AC conversions are ac-coupled and valid from 3 % to 100 % of range.

Range Resolution

600.0 mV 0.1 mV

6.000 V 0.001 V

60.00 V 0.01 V

600.0 V 0.1 V Unspecified

1000 V 1 V Unspecified Unspecified

Low-Pass Filter

[1] Below 10 % of range, add 12 counts.
[2] Frequency range: 1 kHz to 2.5 kHz
[3] Specification increases from -1 % to -6 % at 440 Hz when filter is used.

45 Hz – 65 Hz 30 Hz – 200 Hz 200 Hz – 440 Hz 440 Hz – 1 kHz 1 kHz – 5 kHz 5 kHz – 20 kHz

±(0.7 % + 4)

±(1.0 % + 4)

±(0.7 % + 2)

+1.0 % + 4

±(1.0 % + 4)

[1]

-6.0 % - 4

Accuracy

[3]

±(2 % + 4)

±(2 % + 4)

Unspecified Unspecified Unspecified

[2]

±(2 % + 20)

Unspecified

[1]

46

True-rms Digital Multimeter

Detailed Specifications

DC Voltage, Conductance, and Resistance

Function Range Resolution Accuracy

mV dc 600.0 mV 0.1 mV

6.000 V 0.001 V

V dc

Ω

nS

[1] Add 0.5 % of reading when measuring above 30 MΩ in the 50 MΩ range, and 20 counts below 33 nS in the 60 nS range.
[2] When using the rel function to compensate for offsets.

[3] >40 °C temperature coefficient is 0.1 x (specified accuracy)/°C.

60.00 V 0.01 V

600.0 V 0.1 V

1000 V 1 V

600.0 Ω 0.1 Ω

6.000 kΩ 0.001 kΩ

60.00 kΩ 0.01 kΩ

600.0 kΩ 0.1 kΩ

6.000 MΩ 0.001 MΩ

50.00 MΩ 0.01 MΩ

60.00 nS 0.01 nS

±(0.1 % + 1)

±(0.05 % + 1)

±(0.2 % + 2)

±(0.2 % + 1)

±(0.6 % + 1)

±(1.0 % + 3)

±(1.0 % + 10)

[2]

[1,3]

[1,2,3]

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Temperature

Range Resolution

-200 °C to +1090 °C

-328 °F to +1994 °F

[1] Does not include error of the thermocouple probe.

[2] Accuracy specification assumes ambient temperature stable to ± 1 °C. For ambient temperature changes of ± 5 °C, rated accuracy

applies after 2 hours.

0.1 °C

0.1 °F

Accuracy

±(1.0 % + 10)
±(1.0 % + 18)

[1,2]

AC Current

Function Range Resolution Burden Voltage

μA ac

mA ac

A ac

[1] AC conversions are ac coupled, true rms responding, and valid from 3 % to 100 % of range, except 400 mA range. (5 % to 100 %

of range) and 10 A range (15 % to 100 % or range).

[2] 400 mA continuous. 600 mA for 18 hr maximum.

[3] W 10 A continuous up to 35 °C. <20 minutes on, 5 minutes off at 35 °C to 55 °C. >10 A to 20 A for 30 seconds maximum, 5 minutes

off.

[4] >10 A accuracy unspecified.

600.0 μA 0.1 μA 100 μV/μA

6000 μA 1 μA 100 μV/μA

60.00 mA 0.01 mA 1.8 mV/mA

400.0 mA

[2]

0.1 mA 1.8 mV/mA

6.000 A 0.001 A 0.03 V/A

10.00 A

[3,4]

0.01 A 0.03 V/A

Accuracy

(45 Hz – 2 kHz)

±(1.0 % + 2)

[1]

48

True-rms Digital Multimeter

Detailed Specifications

DC Current

Function Range Resolution Burden Voltage Accuracy

μA dc

mA dc

A dc

[1] 400 mA continuous; 600 mA for 18 hr maximum.
[2] W 10 A continuous up to 35 °C. <20 minutes on, 5 minutes off at 35 °C to 55 °C. >10 A to 20 A for 30 seconds maximum, 5 minutes

off.

[3] >10 A accuracy unspecified.

600.0 μA 0.1 μA 100 μV/μA ±(0.2 % + 4)

6000 μA 1 μA 100 μV/μA ±(0.2 % + 2)

60.00 mA 0.01 mA 1.8 mV/mA

[2,3]

[1]

400.0 mA

6.000 A 0.001 A 0.03 V/A

10.00 A

0.1 mA 1.8 mV/mA

0.01 A 0.03 V/A

±(0.2 % + 4)

±(0.2 % + 2)

±(0.2 % + 4)

±(0.2 % + 2)

Capacitance

Range Resolution Accuracy

10.00 nF 0.01 nF

100.0 nF 0.1 nF

1.000 μF 0.001 μF

10.00 μF 0.01 μF

100.0 μF 0.1 μF

9999 μF 1 μF

[1] With a film capacitor or better, using the rel mode to zero residual.

±(1.0 % + 2)

±(1.0 % + 2)

[1]

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Diode

Range Resolution Accuracy

2.000 V 0.001 V

±(2.0 % + 1)

Frequency

Range Resolution Accuracy

199.99 Hz 0.01 Hz

1999.9 Hz 0.1 Hz

19.999 kHz 0.001 kHz

199.99 kHz 0.01 kHz

>200 kHz 0.1 kHz Unspecified

[1] From 0.5 Hz to 200 kHz and for pulse widths > 2 μs.

±(0.005 % + 1)

Frequency Counter Sensitivity and Trigger Levels

Input Range

600 mV dc 70 mV (to 400 Hz) 70 mV (to 400 Hz) 40 mV

600 mV ac 150 mV 150 mV -

6 V 0.3 V 0.7 V 1.7 V

60 V 3 V

600 V 30 V

1000 V 100 V

Minimum Sensitivity (RMS Sine Wave)

5 Hz – 20 kHz 0.5 Hz – 200 kHz

7 V (≤140 kHz)

70 V (≤14.0 kHz)

200 V (≤1.4 kHz)

Approximate Trigger Level

(DC Voltage Function)

100 V

[1]

4 V

40 V

50

True-rms Digital Multimeter

Detailed Specifications

Duty Cycle (Vdc and mVdc)

Range Accuracy

0.0 % to 99.9 %

[1] 0.5 Hz to 200 kHz, pulse width >2 μs. Pulse width range is determined by the frequency by the frequency of the signal.
[2] For 6 V dc range accuracy is unspecified.

[1]

Within ± (0.2 % per kHz + 0.1 %) for rise times <1 μs.

[2]

Input Characteristics

Function

L

l

Overload

Protection

1000 V rms

1000 V rms

K 1000 V rms

Ω

1000 V rms <7.0 V dc <1.7 V dc <1.9 V dc

Input

Impedance

(nominal)

10 MΩ <100 pF

10 MΩ < 100 pF

(ac-coupled)

Open Circuit
Test Voltage

Common Mode
Rejection Ratio

(1 kΩ unbalance)

> 120 dB at dc, 50 Hz

or 60 Hz

> 120 dB at dc, 50 Hz

or 60 Hz

> 60 dB, dc to 60 Hz

Full Scale Voltage Typical Short Circuit Current

To 6 MΩ

5 MΩ or

60 nS

600 Ω 6 kΩ 60 kΩ 600 kΩ 6 MΩ 50 MΩ

500 μA 100 μA 10 μA 1 μA 0.4 μA 0.2 μA

Normal Mode Rejection

> 60 dB at 50 Hz or 60 Hz

> 60 dB at 50 Hz or 60 Hz

G 1000 V rms <7.0 V dc 2.200 V dc 1.0 mA typical

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MIN MAX Recording

Nominal Response Accuracy

100 ms to 80 %
(dc functions)

120 ms to 80 %
(ac functions)

250 μs (peak)

[1] For 6 V range: 1 ms

[1]

Specified accuracy ±12 counts for changes >200 ms in duration

Specified accuracy ±40 counts for changes >350 ms and inputs >25 % of range

Specified accuracy ±200 counts for changes >250 μs in duration
(add ±100 counts for readings over 6000 counts)
(add ±100 counts for readings in Low Pass mode)

52