Fluke 28 II Ex Parts list manual

PN 3945752
November 2011 Rev. 1, 10/17
© 2011-2017 Fluke Corporation. All rights reserved. Printed in USA. Specifications are subject to change without notice.
All product names are trademarks of their respective companies.
28 II Ex
True-rms Digital Multimeter

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
ООО «Флюк СИАЙЭС»
125167, г. Москва,
Ленинградский проспект дом 37,
корпус 9, подъезд 4, 1 этаж
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
Features......................................................................................................................... 8
Automatic Power-Off ................................................................................................. 14
Input Alert™ Feature ................................................................................................. 14
Power-Up Options ..................................................................................................... 15
Maintenance................................................................................................................... 16
General Maintenance ................................................................................................ 16
Fuse Test .................................................................................................................. 16
How to Replace the Batteries .................................................................................... 17
How to Replace the Fuses ........................................................................................ 20
Service and Parts........................................................................................................... 20

28 II Ex
Getting Started Manual
ii
General Specifications................................................................................................... 23
Detailed Specifications .................................................................................................. 25
AC Voltage................................................................................................................ 25
DC Voltage, Conductance, and Resistance.............................................................. 26
Temperature ............................................................................................................. 27
AC Current................................................................................................................ 27
DC Current................................................................................................................ 28
Capacitance.............................................................................................................. 28
Diode ........................................................................................................................ 29
Frequency................................................................................................................. 29
Frequency Counter Sensitivity and Trigger Levels.................................................... 29
Duty Cycle (Vdc and mVdc)...................................................................................... 30
Input Characteristics ................................................................................................. 30
MIN MAX Recording ................................................................................................. 31

1
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
Safety Instructions 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]
•China: 86-400-921-0835
•Singapore: [phone]
•Anywhere inthe 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
Getting Started Manual
2
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
download the EU 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.
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.

True-rms Digital Multimeter
Ex Safety Information
3
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
Information 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 Information 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-i.s.
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. 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.

28 II Ex
Getting Started Manual
4
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 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.

True-rms Digital Multimeter
Ex Safety Information
5
•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.
•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.

28 II Ex
Getting Started Manual
6
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.

True-rms Digital Multimeter
Errors and Load Restrictions
7
Table 1. Symbols
WWARNING - RISK OF DANGER. Consult user
documentation. XWARNING. HAZARDOUS VOLTAGE. Risk of electric shock.
TDouble Insulated Capacitance
AC (Alternating Current) ODiode
DC (Direct Current) PConforms to European Union directives.
Earth Conforms to relevant South Korean EMC Standards.
Fuse (Conforms to the European Explosive Atmospheres (ATEX)
directive.
Battery. Low battery when displayed. )Certified by CSA Group to North American safety standards.
RContinuity test or continuity beeper tone. Certified by TÜV SÜD Product Service.
Conforms to relevant Australian Safety and EMC standards.
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 low-
voltage MAINS installation.
Measurement Category IV is applicable to test and measuring circuits connected at the source of the building’s low-voltage
MAINS installation.
~
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.

28 II Ex
Getting Started Manual
8
Features
Tables 2 through 5 briefly describe 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.

True-rms Digital Multimeter
Features
9
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)
DC voltage measurement
M600 mV dc voltage range
Push (yellow) for temperature ()
NPush 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.

28 II Ex
Getting Started Manual
10
Table 4. Pushbuttons
Button Switch
Position Function

(Yellow)
NSet to capacitance
MSet to temperature
JTurn on ac low-pass filter
PSet dc or ac current
QSet dc or ac current
C
Any
position Change and set the range for the set function. To go to autoranging, hold the button down for 1 second.
MSets to °C or °F.
D
Any
position
MIN MAX
recording
Frequency
counter
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.

True-rms Digital Multimeter
Features
11
Table 4. Pushbuttons (cont.)
Button Switch
Position Function
E
Continuity
N
MIN MAX
recording
Hz, Duty
Cycle
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.
HAny
position Turns on the button backlight and display backlight, makes them brighter, and turns off the
backlights. Hold Hdown for 1 second to enter the HiRes digit mode. The “HiRes” icon shows in
the display. To go back to the 3-1/2 digit mode, hold Hdown for 1 second. HiRes=19.999.
Any
position 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).
F
(Relative
mode)
Any
position Stores the current measurement as a reference for subsequent measurements. The display is zeroed, and the stored measurement is subtracted from all subsequent measurements.
G
Any
position
except
diode test
Push Gfor frequency measurements.
Push again to go to duty cycle mode.

28 II Ex
Getting Started Manual
12
6
5
4
3
2
78 9 10 11 12
13
14
15
16117
grt09.eps
Figure 1. Display Features
Table 5. Display Features
Number Feature Indication
±Trig Positive or negative slope indicator
for Hz/duty cycle triggering.
XThe continuity beeper is on.
WRelative (REL) mode is active.
Smoothing is active.
Number Feature Indication
- Negative measurement. In relative
mode, this sign shows that the input
is less than the stored reference.
Z
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.
RS AutoHOLD is active.
SDisplay HOLD is active.
Peak Min Max modes and the
response time is 250 μs.

MAX MIN
AVG
Minimum-maximum recording mode.
KLow-pass filter mode. See “Low-
pass Filter”.
€

True-rms Digital Multimeter
Features
13
Table 5. Display Features (cont.)
Number Feature Indication

Low battery. XW Warning: To
avoid false readings, which
could lead to possible electric
shock or personal injury,
replace the battery as soon as
the battery indicator appears.

A, μA, mA amperes (amps), microamp, milliamp
V, mV volts, millivolts
μF, nF microfarad, nanofarad
nS nanosiemens
% Percent. Used for duty cycle
measurements.
Ω, MΩ, kΩohm, megohm, kilohm
Hz, kHz hertz, kilohertz
ODiode test mode
AC DC Alternating current, direct current
Number Feature Indication
°C °F Degrees Celsius, Degrees
Fahrenheit
610000 mV Displays selected range
Auto Autorange mode. Automatically
selects the range with the best
resolution.
Manual Manual range mode
HiRes High resolution (Hi Res) mode
HiRes=19,999

28 II Ex
Getting Started Manual
14
Table 5. Display Features (cont.)
Number Feature Indication
--  Overload condition is detected.
Error Messages
 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.

WTest lead alert. Shows when the test leads are in
the Aor mA/μAterminal and the selected rotary
switch position does not correspond to the terminal
being used.
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 “”. This warning is intended to
stop you from attempting to measure voltage, continuity,
resistance, capacitance, or diode values with the leads
are plugged into a current terminal.
WCaution
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.

True-rms Digital Multimeter
Features
15
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

(Yellow)
Disables automatic power-off feature (Product normally powers off in 30 minutes).
The Product reads “” until is released.
Sets the Product in calibration mode and prompts for a password.
The Product shows “” in the display and enters calibration mode. See 28 II Ex Calibration Information.
CTurns on the smoothing feature. The Product reads “” until Cis released.
DTurns on all LCD segments.
EDisables the beeper for all functions. The Product reads “” until Eis released.
HDisables auto backlight off (backlight normally disables after 2 minutes). The Product reads “” until H
is released.
GSets the Product into the high impedance mode when the mV dc function is used.
The Product reads “” until Gis released.

28 II Ex
Getting Started Manual
16
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 the Product off 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.
It is recommended that the Product be calibrated by Fluke
in two-year intervals.
Fuse Test
As shown in Figure 2, with the Product in the N
function, put a test lead into the jack and place the
probe tip on the other end of the test lead against the
metal of the current input jack. If “” 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 2. 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 7.