Fluke 87 V-an User Manual

Limited permission for the U.S. Government to reproduce Fluke

®

87 V/AN

Digital Multimeter

Service Manual

Item #2153596 is provided pursuant to FAR 52.227.14 Alt. II.

PN 2153596
July 2004

© 2004 Fluke Corporation, All rights reserved. Printed in USA
All product names are trademarks of their respective companies.

LIMITED WARRANTY AND LIMITATION OF LIABILITY

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

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

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

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

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

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

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

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

11/99

To register your product online, visit register.fluke.com

Table of Contents

Title Page

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

Contacting Fluke............................................................................................... 1

Unpacking the Meter......................................................................................... 2

Inspection...................................................................................................... 2

Inspection Interval........................................................................................ 2

Preparations for Use.......................................................................................... 2

Precautions and Safety Information.................................................................. 2

Electrical Symbols ............................................................................................ 4

Specifications.................................................................................................... 5

General Specifications.................................................................................. 5

Detailed Specifications................................................................................. 5

Theory of Operation.......................................................................................... 9

Functional Block Diagram............................................................................ 9

Power Supply and Voltage Reference .......................................................... 10

Function Selection and Overload Protection ................................................ 11

Analog Signal Conditioning......................................................................... 13

VAC.......................................................................................................... 13

VDC.......................................................................................................... 14

mVDC ...................................................................................................... 14

Temperature.............................................................................................. 14

Ohms Below the 6 MΩ Range.................................................................. 14

Ohms in the 6 MΩ & 50 MΩ Range and Siemens in the 60 nS Range.... 15

Continuity in all Ohms and the Siemens Ranges...................................... 15

Capacitance............................................................................................... 15

Diode Test ................................................................................................ 15

mA, µA and AAC..................................................................................... 15

mA, µA and ADC..................................................................................... 16

Active Filter.................................................................................................. 16

800 Hz Low Pass Filter................................................................................. 16

RMS to DC Converter.................................................................................. 16

Analog to Digital Converter ......................................................................... 17

Secondary Analog Circuits........................................................................... 17

Keypad.......................................................................................................... 17

Microprocessor & Support Circuits.............................................................. 18

LCD .............................................................................................................. 18

i

87 V/AN

Service Manual

Backlight....................................................................................................... 18

Beeper........................................................................................................... 18

Troubleshooting................................................................................................ 19

Restoration Actions....................................................................................... 19

Basic Maintenance............................................................................................ 19

Cleaning the Meter........................................................................................ 19

Opening the Meter Case ............................................................................... 20

Accessing the PCA and Replacing the LCD................................................. 21

Reassembling the Meter Case....................................................................... 22

Replacing the Battery.................................................................................... 22

Testing Fuses and Current Circuitry............................................................. 22

Replacing the Fuses...................................................................................... 23

Required Equipment.......................................................................................... 24

Performance Tests............................................................................................. 24

Basic Operability Tests................................................................................. 25

Testing the Fuses .......................................................................................... 25

Testing the Display....................................................................................... 25

Testing the Pushbuttons................................................................................ 27

Testing Meter Accuracy................................................................................ 27

Calibration Adjustment..................................................................................... 29

Calibration Adjustment Counter................................................................... 29

Calibration Adjustment Password................................................................. 29

Changing the Password............................................................................ 29

Restoring the Default Password ............................................................... 30

Meter Buttons Used in the Calibration Steps................................................ 31

Calibration Adjustment Procedure................................................................ 31

Service and Parts............................................................................................... 33

Schematic Diagrams.......................................................................................... 38

ii

List of Tables

Table Title Page

1. Electrical Symbols................................................................................................. 4

2. AC Voltage Function Specifications..................................................................... 6

3. DC Voltage, Resistance, and Conductance Function Specifications..................... 6

4. Temperature Specifications................................................................................... 6

5. Current Function Specifications............................................................................ 7

6. Capacitance and Diode Function Specifications................................................... 7

7. Frequency Counter Specifications......................................................................... 7

8. Frequency Counter Sensitivity and Trigger Levels............................................... 8

9. Electrical Characteristics of the Terminals............................................................ 8

10. MIN MAX Recording Specifications.................................................................... 8

11. Input Path Components......................................................................................... 11

12. Overload Protection Components.......................................................................... 12

13. Required Tools and Equipment............................................................................. 24

14. Display Features.................................................................................................... 25

15. Accuracy Tests ...................................................................................................... 27

16. Calibration Adjustment Steps................................................................................ 32

17. 87 V/AN Final Assembly...................................................................................... 33

18. A1 Main PCA........................................................................................................ 35

iii

87 V/AN

Service Manual

iv

List of Figures

Figure Title Page

1. 87 V/AN Block Diagram....................................................................................... 10

2. Opening the Meter, Battery and Fuse Replacement.............................................. 20

3. Removing LCD Mask to Access LCD.................................................................. 21

4. Testing the Current Input Fuses............................................................................. 23

5. Display Features.................................................................................................... 25

6. Restoring the Default Password ........................................................................... 30

7. 87 V/AN Final Assembly...................................................................................... 34

8. A1 LED PCA......................................................................................................... 39

v

87 V/AN

Service Manual

vi

Introduction

To avoid shock or injury:

• Read “Precautions and Safety Information” before

performing the verification tests or calibration adjustment
procedures documented in this manual.

• Do not perform the verification tests or calibration

adjustment procedures described in this manual unless you
are qualified to do so.

• The information provided in this manual is for the use of

qualified personnel only.

• The 87 V/AN Digital Multimeter contains parts that can be

damaged by static discharge.

• Follow the standard practices for handling static sensitive

devices.

The 87 V/AN Service Manual provides the following information:

XW Warning

WCaution

• Safety information

• Specifications

• Theory of operation

• Basic maintenance (cleaning, replacing the battery and fuses)

• Performance test procedures

• Calibration adjustment procedures

• Replaceable parts and schematics

For complete operating instructions, refer to the 87 V/AN Users Manual.

Contacting Fluke

To contact Fluke or locate the nearest Service Center, call one of the following telephone
numbers:

USA: 1-888-44-FLUKE (1-888-443-5853)
Canada: 1-800-36-FLUKE (1-800-363-5853)
Europe: [phone]
Japan: [phone]
Singapore: [phone]
Anywhere in the world: [phone]

Or, visit Fluke's Web site at www.fluke.com

.

To register your product, visit register.fluke.com

1

87 V/AN

Service Manual

Unpacking the Meter

Inspection

Inspection Interval

Open the Multimeter box. Inside you will find the 87 V/AN Digital Multimeter
(hereafter referred to as “the Meter”) the test leads, the Product Manuals CD, the printed
87 V/AN User Manual, and the printed 87 V/AN Service Manual (this manual). Remove
the Meter from its plastic wrapping.

Inspect all contents for any visible shipping damage. Look for scratches or any other
damage. If the unit is damaged, contact Fluke immediately using the contact information
stated previously.

Inspect the Meter and test leads before each use.

XWWarning

To avoid possible electric shock or personal injury, inspect the
test leads for damaged insulation or exposed metal. Check the
test leads for continuity. Replace damaged test leads before
using the Meter.

Preparations for Use

Before using or servicing the Meter, read all associated safety information. Make sure
you have complete understanding of all safety issues.

Precautions and Safety Information

In this manual, a Warning identifies conditions and actions that pose hazard(s) to the
user; a Caution identifies conditions and actions that may damage the Meter or the test
instruments.

XWWarning

To avoid possible electric shock or personal injury, follow
these guidelines:

• Use this Meter only as specified in this manual or the

protection provided by the Meter might be impaired.

• Do not use the Meter if it is damaged. Before using the

Meter, inspect the case. Look for cracks or missing plastic.
Pay particular attention to the insulation surrounding the
connectors.

• Make sure the battery door is closed and latched before

operating the Meter.

• Replace the battery as soon as the battery indicator (M)

appears.

2

• Remove test leads from the Meter before opening the

battery door.

• Inspect the test leads for damaged insulation or exposed

metal. Check the test leads for continuity. Replace damaged
test leads before using the Meter.

Digital Multimeter

Precautions and Safety Information

• Do not apply more than the rated voltage, as marked on the

Meter, between the terminals or between any terminal and
earth ground.

• Never operate the Meter with the cover removed or the case

open.

• Use caution when working with voltages above 30 V ac rms,

42 V ac peak, or 60 V dc. These voltages pose a shock
hazard.

• Use only the replacement fuses specified in this manual.

• Use the proper terminals, function, and range for

measurements.

• Avoid working alone.

• When measuring current, turn off circuit power before

connecting the Meter in the circuit. Remember to place the
Meter in series with the circuit.

• When making electrical connections, connect the common

test lead before connecting the live test lead; when
disconnecting, disconnect the live test lead before
disconnecting the common test lead.

• Do not use the Meter if it operates abnormally. Protection

may be impaired. When in doubt, have the Meter serviced.

• Do not operate the Meter around explosive gas, vapor, or

dust.

• Use only a single 9 V battery, properly installed in the Meter

case, to power the Meter.

• When servicing the Meter, use only specified replacement

parts.

• When using probes, keep fingers behind the finger guards

on the probes.

• Do not use the Low Pass Filter option to verify the presence

of hazardous voltages. Voltages greater than what is
indicated may be present. Make a voltage measurement
without the filter to detect the possible presence of
hazardous voltage, then select the filter function.

XCaution

To avoid possible damage to the Meter 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.

• Before measuring current, check the Meter's fuses.

See " Testing Fuses (F1 and F2) ”.

3

87 V/AN

Service Manual

Electrical Symbols

Electrical symbols used on the Meter and in this manual are explained in Table 1.

Table 1. Electrical Symbols

B
F

X

W

M

R

t

CAT III

s

AC (Alternating Current)

DC (Direct Current)

Hazardous voltage.

Risk of Danger. Important information.
See Manual.

Battery

Continuity test or continuity beeper tone.

Underwriters Laboratories

IEC overvoltage category III

CAT III equipment is designed to protect
against transients in equipment in fixed­equipment installations, such as
distribution panels, feeders and short
branch circuits, and lighting systems in
large buildings.

Inspected and licensed by TÜV Product Services.

I

P

$

E

G

CAT IV

J

T

Earth ground

Fuse

Conforms to European Union
directives

Conforms to relevant Canadian
Standards Association directives

Double insulated

Capacitance

Diode
IEC overvoltage category IV

CAT IV equipment is designed to
protect against transients from the
primary supply level, such as an
electricity meter or an overhead or
underground utility service.

4

Digital Multimeter

Specifications

Specifications

General Specifications

Maximum Voltage between any Terminal and Earth Ground: 1000 V rms

W Fuse Protection for mA or µA inputs: 44/100 A, 1000 V FAST Fuse
W Fuse Protection for A input: 11 A, 1000 V FAST Fuse

Display: Digital: 6000 counts updates 4/sec. The Meter also has 19,999 counts in high-resolution mode.
Analog Bargraph: 33 segments, updates 40/sec. Frequency: 19,999 counts, updates 3/sec at > 10 Hz.

Temperature: Operating: -20 °C to +55 °C; Storage: -40 °C to +60 °C
Altitude: Operating: 2000 m; Storage: 10,000 m
Temperature Coefficient: 0.05 x (specified accuracy)/ °C (< 18 °C or > 28 °C)
Electromagnetic Compatibility: All ranges unless otherwise noted: In an RF field of 3 V/m total

accuracy = specified accuracy + 20 counts
Except: Temperature not specified.

Relative Humidity: 0 % to 90 % (0 °C to 35 °C); 0 % to 70% (35 °C to 55 °C)
Battery Type: 9 V zinc, NEDA 1604 or 6F22 or 006P
Battery Life: 400 hrs typical with alkaline (with backlight off)
Vibration: Per MIL-PRF-28800 for a Class 2 instrument
Shock: 1 Meter drop per IEC 61010-1:2001
Size (HxWxL): 1.25 in x 3.41 in x 7.35 in (3.1 cm x 8.6 cm x 18.6 cm)
Size with Holster and Flex-Stand: 2.06 in x 3.86 in x 7.93 in (5.2 cm x 9.8 cm x 20.1 cm)
Weight: 12.5 oz (355 g)
Weight with Holster and Flex-Stand: 22.0 oz (624 g)
Safety: Complies with ANSI/ISA S82.01-2004, CSA 22.2 No. 1010.1:2004 to 1000 V Overvoltage

Category III, IEC 664 to 600 V Overvoltage Category IV. UL listed to UL61010-1. Licensed by TÜV to
EN61010-1.

Detailed Specifications

For all detailed specifications:
Accuracy is given as ±([% of reading] + [number of least significant digits]) at 18 °C to

28 °C, with relative humidity up to 90 %, for a period of one year after calibration
adjustment. In the 4 ½-digit mode, multiply the number of least significant digits
(counts) by 10. AC conversions are ac-coupled and valid from 3 % to 100 % of range.
The Meter is true rms responding. AC crest factor can be up to 3 at full scale, 6 at half
scale. For non-sinusoidal wave forms add -(2 % Rdg + 2 % full scale) typical, for a crest
factor up to 3.

Tables 2 through 10 list the Meter’s detailed specifications.

5

87 V/AN

is a true rms responding meter. When the input leads are shorted together in the ac functions, the Meter

Service Manual

Table 2. AC Voltage Function Specifications

Function Range Resolution

600.0 mV

2,4

K

6.000 V

60.00 V

600.0 V

1000 V 1 V
Low pass filter ± (0.7 % + 2)

1. Below 10 % of range, add 12 counts.

2. The Meter
may display a residual reading between 1 and 30 counts. A 30 count residual reading will cause only a 2-digit
change for readings over 3 % of range. Using REL to offset this reading may produce a much larger constant error
in later measurements.

3. Frequency range: 1 kHz to 2.5 kHz.

4. A residual reading of up to 13 digits with leads shorted, will not affect stated accuracy above 3 % of range.

5. Specification increases from -1% at 200 Hz to -6% at 440 Hz when filter is in use.

0.1 mV

0.001 V

0.01 V

0.1 V

45 - 65 Hz 30 - 200 Hz

± (0.7 % + 4)

± (0.7 % + 2)

± (1.0 % + 4)

200 - 440 Hz

± (1.0 % + 4)

+1 % + 4

-6 % - 45

Accuracy

440 Hz - 1

kHz

unspecified

1 - 5 kHz 5 - 20 kHz

± (2.0 % + 4)

± (2.0 % + 4)

unspecified unspecified
unspecified unspecified

± (2.0 % + 20)

3

unspecified

Table 3. DC Voltage, Resistance, and Conductance Function Specifications

Function Range Resolution Accuracy

6.000 V

L

F

mV

e

nS

1. When using the REL ∆ function to compensate for offsets.

2. Add 0.5 % of reading when measuring above 30 MΩ in the 50 MΩ range.

60.00 V

600.0 V
1000 V

600.0 mV 0.1 mV ± (0.1 % + 1)

600.0 Ω

6.000 kΩ

60.00 kΩ

600.0 kΩ

6.000 MΩ

50.00 MΩ

60.00 nS

0.001 V

0.01 V

0.1 V
1 V

0.1 Ω

0.001 kΩ

0.01 kΩ

0.1 kΩ

0.001 MΩ

0.01 MΩ

0.01 nS

± (0.05 % + 1)
± (0.05 % + 1)
± (0.05 % + 1)
± (0.05 % + 1)

± (0.2 % + 2)1
± (0.2 % + 1)
± (0.2 % + 1)
± (0.6 % + 1)
± (0.6 % + 1)
± (1.0 % + 3)
± (1.0 % + 10)

2

1

1

Table 4. Temperature Specifications

Temperature Resolution Accuracy

-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
rated accuracy applies after 1 hour.

0.1 °C

0.1 °F

± 1 °C. For ambient temperature changes of ± 5 °C,

6

1 % + 10
1 % + 18

1,2

Digital Multimeter

Table 5. Current Function Specifications

Function Range Resolution Accuracy

mA

\

(45 Hz to 2 kHz)

mA
[

µA B

(45 Hz to 2 kHz)

µAF

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. The Meter is a true rms responding meter. When the input leads are shorted together in the ac functions, the
Meter may display a residual reading between 1 and 30 counts. A 30 count residual reading will cause only a 2
digit change for readings over 3 % of range. Using REL to offset this reading may produce a much larger constant
error in later measurements

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

4. 400 mA continuous; 600 mA for 18 hrs maximum.

60.00 mA

400.0 mA

6.000 A

3

10.00 A

60.00 mA

400.0 mA

6.000 A

3

10.00 A

600.0 µA
6000 µA

600.0 µA
6000 µA

4

4

0.01 mA

0.1 mA

0.001 A

0.01 A

0.01 mA

0.1 mA

0.001 A

0.01 A

0.1 µA
1 µA

0.1 µA
1 µA

± (1.0 % + 2)
± (1.0 % + 2)
± (1.0 % + 2)
± (1.0 % + 2)

± (0.2 % + 4)
± (0.2 % + 2)
± (0.2 % + 4)
± (0.2 % + 2)

± (1.0 % + 2)
± (1.0 % + 2)

± (0.2 % + 4)
± (0.2 % + 2)

1, 2

Burden Voltage (typical)

1.8 mV/mA

1.8 mV/mA

0.03 V/A

0.03 V/A

1.8 mV/mA

1.8 mV/mA

0.03 V/A

0.03 V/A
100 µV/µA

100 µV/µA

100 µV/µA
100 µV/µA

Specifications

Table 6. Capacitance and Diode Function Specifications

Function Range Resolution Accuracy

E 10.00 nF

100.0 nF

1.000 µF

10.00 µF

100.0 µF
9999 µF

0.01 nF

0. 1 nF

0.001 µF

0.01 µF

0.1 µF
1 µF

± (1 % + 2)1
± (1 % + 2)
± (1 % + 2)
± (1 % + 2)
± (1 % + 2)
± (1 % + 2)

1

G 3.000 V 0.001 V ± (2 % + 1)

1. With a film capacitor or better, using Relative mode to zero residual.

Table 7. Frequency Counter Specifications

Function Range Resolution Accuracy

Frequency
(0.5 Hz to 200 kHz,
pulse width > 2 µs)

199.99

1999.9

19.999 kHz

199.99 kHz
> 200 kHz

0.01 Hz

0.1 Hz

0.001 kHz

0.01 kHz

0.1 kHz

± (0.005 % + 1)
± (0.005 % + 1)
± (0.005 % + 1)
± (0.005 % + 1)

unspecified

7