Fluke 28IIEX User manual

November 2011
© 2011 Fluke Corporation. All rights reserved. Specifications are subject to change without notice.
All product names are trademarks of their respective companies.
28 II Ex
True-rms Digital Multimeter
Users Manual

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.
Fluke Europe B.V.
P.O. Box 1186
5602 BD Eindhoven
The Netherlands
11/99

i
Table of Contents
Title Page
Introduction .................................................................................................................... 1
How to Contact Fluke..................................................................................................... 1
Safety Information .......................................................................................................... 2
EX Safety Information .................................................................................................... 2
Errors and Load Restrictions ..................................................................................... 6
Ex-Certification Data.................................................................................................. 7
Features......................................................................................................................... 9
Automatic Power-Off ................................................................................................. 15
Input Alert™ Feature ................................................................................................. 15
Power-Up Options ..................................................................................................... 16
How to Make Measurements.......................................................................................... 17
AC and DC Voltage Measurements........................................................................... 17
Zero Input Behavior of True-rms Meters.................................................................... 18
Low-Pass Filter.......................................................................................................... 18
Temperature Measurements ..................................................................................... 19

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Users Manual
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Continuity Tests ........................................................................................................ 20
Resistance Measurements ....................................................................................... 22
How to Use Conductance for High Resistance or Leakage Tests ............................ 24
Capacitance Measurements ..................................................................................... 25
Diode Tests............................................................................................................... 26
AC or DC Current Measurements............................................................................. 28
Frequency Measurements ........................................................................................ 31
Duty Cycle Measurements........................................................................................ 33
How to Determine Pulse Width ................................................................................. 34
HiRes Mode................................................................................................................... 34
MIN MAX Recording Mode ............................................................................................ 35
Smooth Feature (Power Up Option Only) ...................................................................... 35
AutoHOLD Mode ........................................................................................................... 37
Relative Mode................................................................................................................ 37
Maintenance .................................................................................................................. 38
General Maintenance................................................................................................ 38
Fuse Test.................................................................................................................. 38
How to Replace the Batteries.................................................................................... 39
How to Replace the Fuses........................................................................................ 42
Service and Parts .......................................................................................................... 42
General Specifications................................................................................................... 46
Detailed Specifications .................................................................................................. 48
AC Voltage................................................................................................................ 48
DC Voltage, Conductance, and Resistance.............................................................. 49
Temperature ............................................................................................................. 50
AC Current................................................................................................................ 50
DC Current................................................................................................................ 51
Capacitance.............................................................................................................. 51
Diode ........................................................................................................................ 52

Contents (continued)
iii
Frequency ................................................................................................................. 52
Frequency Counter Sensitivity and Trigger Levels .................................................... 52
Duty Cycle (Vdc and mVdc) ...................................................................................... 53
Input Characteristics.................................................................................................. 53
MIN MAX Recording.................................................................................................. 54

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v
List of Tables
Table Title Page
1. Symbols................................................................................................................................. 8
2. Inputs .................................................................................................................................... 9
3. Rotary Switch Positions......................................................................................................... 10
4. Pushbuttons .......................................................................................................................... 11
5. Display Features ................................................................................................................... 13
6. Power-Up Options ................................................................................................................. 16
7. Functions and Trigger Levels for Frequency Measurements................................................. 32
8. MIN MAX Functions .............................................................................................................. 36
9. Approved Batteries................................................................................................................ 40
10. Replacement Parts................................................................................................................ 43
11. Accessories........................................................................................................................... 45

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vii
List of Figures
Figure Title Page
1. Display Features ................................................................................................................... 13
2. AC and DC Voltage Measurements ...................................................................................... 17
3. Low-Pass Filter...................................................................................................................... 19
4. Continuity Tests..................................................................................................................... 21
5. Resistance Measurements.................................................................................................... 23
6. Capacitance Measurements.................................................................................................. 25
7. Diode Tests ........................................................................................................................... 27
8. Current Measurements.......................................................................................................... 29
9. Components of Duty Cycle Measurements ........................................................................... 33
10. Current Fuse Test ................................................................................................................. 39
11. Battery and Fuse Replacement ............................................................................................. 41
12. Replacement Parts................................................................................................................ 44

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Users Manual
viii

1
Introduction
WX 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.
The Product is designed for operation in potentially
explosive areas of Zone 1, 2, 21, 22, and MI as specified
in Directive 1999/92/EC (ATEX 137) and 94/9/EC (ATEX
95). There can be dangerous consequences If you do not
follow these instructions.
Read the entire Users Manual before you use the
Product.
How to Contact Fluke
To contact Fluke, call one of the following telephone
numbers:
•Technical Support USA: 1-800-44-FLUKE (1-800-
443-5853)
•Calibration/Repair USA: 1-888-99-FLUKE (1-888-
993-5853)
•Canada: 1-800-36-FLUKE (1-800-363-5853)
•Europe: [phone]
•Japan: [phone]
•Singapore: [phone]
•Anywhere in the world: [phone]
Or, visit Fluke's website at www.fluke.com.
To register your product, visit http://register.fluke.com.
To see, print, or download the latest manual supplement,
visit http://us.fluke.com/usen/support/manuals.

28 II Ex
Users Manual
2
Safety Information
The Product complies with:
•ISA-82.02.01
•CAN/CSA-C22.2 No. 61010-1-04
•IEC Standard No. 61010-1:2001
•Measurement Category III, 1000V, Pollution
Degree 2
•Measurement Category IV, 600V, Pollution
Degree 2
•Industrial use in potentially explosive areas of
zone 1, 2, 21, 22, or MI, in accordance with
ATEX requirements (ATEX 137) (see the EX
safety instructions & regulations section)
In this manual, a Warning identifies conditions and
actions that can be dangerous to the user. A Caution
identifies conditions and actions 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
download the EC declaration of conformity and
Ex certificate for this product. You can also order
them 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.
Please read through this manual before you start to use
the Product.
If there is a question (because of translation and/or
printing errors), refer to the English manual.

True-rms Digital Multimeter
EX Safety Information
3
WX 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 the “How to Replace the
Batteries” section 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
the “How to Replace the Fuses” section
for a list of approved fuses.
•Use the Product only when the specified
connection values are met.
•After you use the Product on a non-
intrinsically safe protected circuit, wait
3 minutes before you take the Product
into an Ex-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.
•Do not use the Product in zone 0 and 20.
Measurements on intrinsically safe
connections that go into zone 0 or 20 are
permitted if the connection values are
met.

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Users Manual
4
WX 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 oils, hydraulic
fluid, or grease.
•Do not install the Product in a fixed
installation.
WX 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 Information” section
for additional warnings on Product use
in hazardous areas.
•Use the Product only as specified, or the
protection supplied by the Product can
be compromised.
•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.

True-rms Digital Multimeter
EX Safety Information
5
•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.
•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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Users Manual
6
WCaution
To avoid 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.

True-rms Digital Multimeter
EX Safety Information
7
Ex-Certification Data
•Ex-Type certificate no:
•Ex-Designation:
•Power Supply:
•CE: CE0102
•Operating Temperature: -15 °C to 50 °C
•Storage Temperature: -55 °C to +60 °C
•Batteries: 3 AAA Alkaline batteries, NEDA 24A IEC
LR03. Table 9 shows the approved batteries for this
Product.
For connections to intrinsically-safe circuits, observe
these Product connections:
Voltage – measurement input Ui= 65 V:
U0= 9.54 V Ui= 65 V
C0 = 3.6 μF Ci= negligible
I0 = 3.7 mA Ii= negligible
L0 = 1000 mH Li= negligible
P0 = 3.4 mW
Current – measurement input Ii= 5 A:
U0= 0 V Ui= 65 V
C0 = 1000 μF Ci= negligible
I0 = 9.7 μA Ii= 5 A
L0 = 1000 mH Li= negligible
P0 = 0 mWH
mA/μA Jack
U0= 1.94 V Ui= 65 V
C0 = 1000 μF Ci= negligible
I0 = 9.7 μA Ii= Internally limited by a 440 mA fuse
L0 = 1000 mH Li= negligible
P0 = negligible
For measurements on protected electric circuits:
•Approved for Zones 2 and 1, device group II,
explosion group IIC (explosive gases, vapors and
mist), temperature class T4.
•Approved for Zones 21 and 22, device group II,
explosion group IIIC, conducting and non-conducting
dust, fibers, and flyings.
•Approved for use in mines. Device group I, explosion
group I, methane, and coal dust.

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Users Manual
8
Table 1. Symbols
AC (Alternating Current) JEarth ground
DC (Direct Current) IFuse
XHazardous voltage PConforms to European Union directives.
WRisk of Danger. Important information. See
Manual. Diode
Battery. Low battery when displayed. TDouble insulated
RContinuity test or continuity beeper tone. Capacitance
CAT III
IEC Overvoltage Category III
CAT III equipment is designed to protect
against transients in equipment in fixed-
equipment installations, such as
distribution panels, feeders and short
branch circuits, and lighting systems in
large buildings.
CAT IV
IEC Overvoltage Category IV
CAT IV equipment is designed to protect against
transients from the primary supply level, such as an
electricity Product or an overhead or underground
utility service.
(Conforms to ATEX directive. Conforms to relevant Australian standards.
®Inspected and licensed by TÜV Product
Services. ÆConforms to CAN/CSA-C22.2 No. 61010-1 2nd, + Amendment 1.
~Do not dispose of this product as unsorted municipal waste. Go to Fluke’s website for recycling information.

True-rms Digital Multimeter
Features
9
Features
Tables 2 through 5 show the features of the Product.
Table 2. Inputs
12
4
3
grt01.eps
Item Terminal Description
A 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.
COM Return terminal for all measurements.

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10
Table 3. Rotary Switch Positions
Switch Position Function
Any Position When the Product is turned on, the Product model number briefly shows on the display.
JAC voltage measurement
Push (yellow) for low-pass filter (K)
LDC voltage measurement
M600 mV dc voltage range
Push (yellow) for temperature ()
N
Push Efor continuity test.
eResistance measurement
Push (yellow) for capacitance measurement.
ODiode test
PAC current measurements from 0 mA to 10.00 A
Push (yellow) for dc current measurements, from 0 mA to 10.00 A.
QAC current measurements from 0 μA to 6000 μA
Push (yellow) for dc current measurements from 0 μA to 6000 μA.