Fluke 771 Use and care manual

®
771
Milliamp Process Clamp Meter
Calibration Manual
November 2007
© 2007 Fluke Corporation, All rights reserved. Printed in USA. Product 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 3 years (one year for cable and
clamp) from the date of purchase. This warranty does not cover fuses, disposable batteries or damage from
accident, neglect, misuse 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, send your
defective Meter to the nearest Fluke Authorized 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
To register your product online, visit http://register.fluke.com

i
Table of Contents
Title Page
Introduction........................................................................................................ 1
Contacting Fluke................................................................................................ 2
Safety Information ............................................................................................. 2
Symbols ............................................................................................................. 3
Specifications..................................................................................................... 4
Getting Acquainted with the Meter.................................................................... 5
Maintenance....................................................................................................... 6
Cleaning the Meter ........................................................................................ 6
Battery Replacement ..................................................................................... 6
Performance Tests.............................................................................................. 8
Required Equipment...................................................................................... 8
Testing the Batteries ...................................................................................... 8
Testing the Display........................................................................................ 9
Display Hold Test.......................................................................................... 9
Backlight Test................................................................................................ 9
Spotlight LED Test........................................................................................ 9
Zero Test........................................................................................................ 9
Accuracy Tests .............................................................................................. 9
Calibration Adjustment...................................................................................... 11
Adjustment Subroutines ................................................................................ 11
Front Panel Operation for Adjustment .......................................................... 11
Calibration Error Messages ........................................................................... 12
Calibration Adjustment Procedure ................................................................ 12
Temperature Adjustment Procedure.............................................................. 13
Low Range Adjustment Procedure................................................................ 13
High Range Adjustment Procedure ............................................................... 13
Phase Adjustment Procedure......................................................................... 14
User Replaceable Parts ...................................................................................... 15

771
Calibration Manual
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iii
List of Tables
Table Title Page
1. Symbols.................................................................................................................. 3
2. Required Equipment............................................................................................... 8
3. Accuracy Tests ....................................................................................................... 10
4. Error Messages....................................................................................................... 12
5. Replaceable Parts ................................................................................................... 15

771
Calibration Manual
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v
List of Figures
Figure Title Page
1. The 771 Milliamp Process Clamp Meter ............................................................... 5
2. Changing the Batteries ........................................................................................... 7
3. Display Test ........................................................................................................... 9
4. Accessing the Calibration Button........................................................................... 12
5. Phase Adjustment................................................................................................... 14
6. Replaceable Parts ................................................................................................... 16

771
Calibration Manual
vi

1
771
Milliamp Process Clamp Meter
Introduction
XW Warning
To avoid electric shock or personal injury, do not perform the
calibration verification tests or calibration 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.
This manual provides the complete verification and adjustment procedure for the
771 Milliamp Process Clamp Meter (referred to in this manual as the Meter).
The Meter allows closed-case calibration using reference sources. It measures the
reference signals, calculates the correction factors, and stores them in memory. The
instrument should be calibrated after repair, or if it fails a performance test.
The 771 Calibration Manual provides the following information:
•Precautions and safety information
•Specifications
•Basic maintenance
•Calibration verification procedure
•Replaceable parts and accessories
For complete operating instructions, refer to the 771 Instruction Sheet.

771
Calibration Manual
2
Contacting Fluke
To contact Fluke, call:
1-888-993-5853 in USA
1-800-363-5853 in Canada
[phone] in Europe
[phone] in Japan
[phone] in Singapore
[phone] from anywhere in the world
Or, visit Fluke’s Web site at www.fluke.com
To register your product, visit http://register.fluke.com
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 test instrument.
The design and manufacture of the device conforms to the latest state of technology and
the safety standards specified in IEC 61010-1/ 2nd edition. If used improperly, there is a
risk of damage to persons and property.
XWWarning
To avoid possible electric shock or personal injury, follow these
guidelines:
•Read this manual before use and follow all safety
instructions.
•Use the Meter only as specified in this manual; otherwise,
the Meter's safety features may be impaired.
•Before each use inspect Meter and cable for damage. Look
for cracks and missing portions of the clamp and cable. Do
not use if clamp is damaged.
•Use caution when working with voltages above 33 V rms
47 V peak or 70 V dc these voltages pose a shock hazard.
•Do not use to measure ac current.
•Do not use to measure dc mA in circuits carrying more
than 300 V CAT II.
•Avoid working alone so assistance can be rendered in an
emergency.
•Use extreme caution when working around bare
conductors or bus bars. Contact with the conductor could
result in electric shock.
•To avoid false readings that can lead to electrical shock
and injury, replace the batteries as soon as the low battery
indicator (B) appears.
•Adhere to local and national safety codes. Individual
protective equipment must be used to prevent shock and
arc blast injury where hazardous live conductors are
exposed.

Milliamp Process Clamp Meter
Symbols
3
•When measuring, keep fingers behind the Tactile Barrier.
See Figure 1.
•Not for use with non-insulated conductors.
WCaution
To avoid damage to the Meter, do not open the Meter for
cleaning. Do not use solvents to clean it, and do not immerse it
in liquid.
Symbols
Table 1 explains the symbols that are used on the Meter or in this manual.
Table 1. Symbols
-Do not apply around, or remove from HAZARDOUS LIVE conductors
WRisk of danger. Important information. See Users Manual.
X Risk of Electrical Shock
TEquipment protected by double or reinforced insulation
M Battery
B Low Battery
PConforms to relevant European Union directives
FDC (Direct Current)
~Do not dispose of this product as unsorted municipal waste. Go to Fluke’s web site for
recycling information.
;
N10140 Conforms to relevant Australian standards
)Conforms to relevant Canadian and US standards
CAT II
300 V
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.

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Calibration Manual
4
Specifications
Current Ranges ±20.99 mA ±21.0 mA - ±99.9 mA
Resolution 0.01 mA 0.1 mA
Accuracy
20.99 mA range
99.9 mA range
0.2 % reading ±5 digits
1 % reading ±5 digits
Maximum Reading ±99.9 mA
Influence of Earth’s Field < 0.20 mA
Battery 2 AA 1.5 V Alkaline, IEC LR6
Working hours 45 hours
Size (H X W X L) 59 mm x 38 mm x 212 mm (2.32 in x 1.49 in x 8.34 in)
(with clamp nested)
Weight 260 g (9.17 oz) (Including battery)
Operating Temperature -10 to 50 °C
(14 to 122 °F)
Storage Temperature -25 to 70 °C
(-13 to 158 °F)
Operating Humidity < 90 % @ <30 °C (86 °F)
<75 % @ 30 to 50 °C (86 to 122 °F)
Operating Altitude 0 to 2000 m (1.24 miles)
Storage Altitude None
IP Rating IP 40
Vibration Requirements Random 2 g, 5 to 500 Hz
EMI, RFI, EMC Meets all applicable requirements in EN 61326-1
Temperature Coefficients 0.1x(specified accuracy)/°C
(< 18 °C or > 28 °C)
Measurement Category IEC 61010-1
61010-2-032
CAT II 300 V
CAT II Equipment is designed to protect against transients from
energy-consuming equipment supplied from the fixed installation,
such as TVs, PCs, portable tools, and other household appliances.
Agency Approvals P, ), ;, FCC
N10140

Milliamp Process Clamp Meter
Getting Acquainted with the Meter
5
Getting Acquainted with the Meter
Figure 1 shows the Meter functions and features.
1
2
3
4
5
6
7
8
9
ege01a.eps
Number Description
A Turns the Meter on and off. When the Meter is in sleep mode, press this button to wake it up.
B Captures and holds the current reading
C Removes interference and zeros the display
D Measurement spotlight LED button
E Measurement spotlight LED
F Detachable clamp
G Turns the backlight off and on
H LCD
I Tactile Barrier docked and un-docked
Figure 1. The 771 Milliamp Process Clamp Meter

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Calibration Manual
6
Maintenance
XWWarning
To avoid possible electric shock or personal injury, repairs or
servicing not covered in this manual should be performed only
by qualified personnel.
Cleaning the Meter
XWWarning
To avoid electrical shock, remove any input signals before
cleaning.
WCaution
To avoid damaging the Meter, do not use aromatic
hydrocarbons or chlorinated solvents for cleaning. These
solutions will react with the plastics used in the Meter.
Clean the instrument case with a damp cloth and mild detergent.
Battery Replacement
XWWarning
To avoid false readings, that could lead to possible electric
shock or personal injury, replace the battery as soon as the low
battery indicator (B) appears.
To replace the batteries, see Figure 2:
1. Turn the Meter off.
2. Use a flat head screwdriver to loosen the battery access door fastener, and remove the
door from the case bottom.
3. Remove the batteries.
4. Replace the batteries with two new AA batteries.
5. Reattach the battery access door to the case bottom and tighten the fastener.

Milliamp Process Clamp Meter
Maintenance
7
ege02.eps
Figure 2. Changing the Batteries

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Calibration Manual
8
Performance Tests
XWWarning
To avoid electrical shock, personal injury, or fire:
•Do not perform the verification tests or calibration
adjustment described in this manual unless you are
qualified to do so.
•Repairs or servicing should be performed only by qualified
personnel.
The following tests are used to verify the functions of the Meter. If the Meter fails any of
the verification tests, repair is necessary. For service, see Contacting Fluke.
Required Equipment
Required equipment for the performance tests is listed in Table 2. If the recommended
models are not available, equipment with equivalent specifications may be used.
Table 2. Required Equipment
Equipment Minimum Required
Characteristics Recommended Model
Calibrator
DC Current Accuracy:
Range:
20.99 mA = 0.11 %
99.9 mA = 0.375 %
5520A or equivalent
1 loop insulated copper wire Insulated 18 gauge, minimum, copper
wire, 6 inch diameter
Testing the Batteries
Prior to performing the following tests, check the batteries with a multimeter and replace
as necessary. See Battery Replacement.

Milliamp Process Clamp Meter
Performance Tests
9
Testing the Display
1. Press and hold Awhile powering on the Meter.
2. Compare the Meter display to Figure 3.
3. Check all display segments for clarity and contrast.
fdp1.eps
Figure 3. Display Test
Display Hold Test
1. Power on the Meter and allow time for the normal operating display to appear.
2. Press Hand observe that Iappears on the display. Iflashes at 3 to 4
second intervals.
Backlight Test
1. Power on the Meter and allow time for the normal operating display to come up.
2. Press Cand observe that the backlight comes on.
Spotlight LED Test
1. Power on the Meter and allow time for the normal operating display to come up.
2. Press Land observe that the spotlight LED comes on.
Zero Test
1. Power on the Meter and allow time for the normal operating display to come up.
2. Press A. The main display momentarily reads 0.00, and the percentage scale
momentarily reads -25.0%.
Accuracy Tests
Accuracy specifications are valid for 1 year after calibration when measured at an
operation temperature of 18 °C to 28 °C. Allow the Meter to stabilize at room
temperature prior to performing the accuracy tests.
Table 3 lists the required performance test points for verifying Meter accuracy. A zero
adjustment must be performed prior to completing each performance test point.

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Calibration Manual
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Perform the tests as follows:
1. Connect a single loop of 14 gauge insulated copper wire to the calibrator AUX output
terminals.
2. Clamp the Meter jaw around the wire with the jaw arrow pointing toward the
calibrator HI terminal.
3. Output 0 mA dc from the calibrator.
4. Press Aon the Meter.
5. Set the calibrator output for the value in Step 1 of Table 3.
6. Compare the Meter displayed reading with the display reading limits in Table 3.
7. Complete steps 2-4 for each calibrator output setting in Table 3.
8. If the Meter fails to meet any of the Display Reading Limits, it requires calibration
adjustment, or repair. See Calibration Adjustment or Contacting Fluke.
Table 3. Accuracy Tests
Unit Under Test
Display Reading Limits
Step Unit Under Test
Function
Calibrator
Output Setting Lower Limit Upper Limit
1. 100 mA dc 98.5 101.5
2. -100 mA dc -100.7 -99.3
3. 20 mA dc 19.91 20.09
4. -20 mA dc -20.09 -19.91
5. 12 mA dc 11.93 12.07
6. -12 mA dc -12.07 -11.93
7. 4 mA dc 3.94 4.06
8.
mA dc
-4 mA dc -4.06 -3.94

Milliamp Process Clamp Meter
Calibration Adjustment
11
Calibration Adjustment
Adjustment Subroutines
The Meter features closed-case calibration adjustment using a known reference source.
The Meter measures the applied reference source, calculates correction factors, and stores
the correction factors in nonvolatile memory.
There are four adjustment subroutines in the Meter adjustment procedure:
•Low Range (±20 mA)
•High range (±100 mA)
•Temperature
•Phase
Note
Temperature adjustment should always be performed prior to performing
the other adjustment routines. The phase adjustment routine is ONLY
required if the unit is repaired or the current clamp is replaced.
Front Panel Operation for Adjustment
Use a small probe to press the calibration button once to enter the Meter’s calibration
mode. The calibration button is usually covered by the factory calibration seal. A second
press of the button saves new calibration constants and exits calibration mode.
See Figure 4.
In calibration mode, Cis used to select subroutines: low range, high range, temperature,
or phase. A short press of C(<1 second) will toggle between low and high range
subroutines. A long press (>1 second) will toggle between temperature and phase
subroutines.
•Pressing Ais valid for all subroutines and normal operation. Pressing Awill
zero the reading.
•In the low and high range subroutines, Hand Lare used to adjust the negative
and positive gain of the range.
•In the temperature subroutine, only His valid for adjustment.
•In the phase subroutine, Hand Lare used to adjust the phase of two
sensor-excitation signals by increasing or decreasing a parameter.

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Calibration Manual
12
Calibration Button
fdp3.eps
Figure 4. Accessing the Calibration Button
Calibration Error Messages
Table 4 lists the calibration error messages that can be shown on the Meter display.
The suggested actions to eliminate messages are also listed.
Table 4. Error Messages
Error
Message Cause of Error Suggested Action
CAL ERR1
The difference between the input level
and the zero point is less than the
minimal threshold when performing low
range and high range adjustments.
Check current loop and ensure correct
current is generated.
CAL ERR2 Calibration parameter checksum
failure.
Execute all adjustments including
temperature and phase.
CAL ERR3 Code checksum failure. The Meter requires repair.
Calibration Adjustment Procedure
Allow the Meter to stabilize to room temperature before beginning the calibration
adjustment.
To prepare for adjustment:
1. Remove the battery door and calibration seal.
2. Clamp the current loop in the current flow direction where required.
3. Turn the meter on and wait at least 10 seconds for warming up.
4. Press the hidden calibration button with a probe to enter calibration mode.
See Figure 4.