Agilent Technologies U1271A User manual

Agilent Technologies
Agilent U1271A/U1272A
Handheld Digital
Multimeter
Service Guide

II U1271A/U1272A Service Guide
Notices
© Agilent Technologies, Inc. 2010
No part of this manual may be reproduced in
any form or by any means (including elec-
tronic storage and retrieval or translation
into a foreign language) without prior agree-
ment and written consent from Agilent
Technologies, Inc. as governed by United
States and international copyright laws.
Manual Part Number
U1271-90020
Edition
First Edition, December 27, 2010
Agilent Technologies, Inc.
5301 Stevens Creek Blvd.
Santa Clara, CA 95051 USA
Warranty
The material contained in this document is
provided “as is,” and is subject to change,
without notice, in future editions. Further,
to the maximum extent permitted by the
applicable law, Agilent disclaims all war-
ranties, either express or implied, with
regard to this manual and any information
contained herein, including but not limited
to the implied warranties of merchantabil-
ity and fitness for a particular purpose.
Agilent shall not be liable for errors or for
incidental or consequential damages in
connection with the furnishing, use, or
performance of this document or of any
information contained herein. Should Agi-
lent and the user have a separate written
agreement with warranty terms covering
the material in this document that conflict
with these terms, the warranty terms in
the separate agreement shall control.
Technology Licenses
The hardware and or software described in
this document are furnished under a license
and may be used or copied only in accor-
dance with the terms of such license.
Restricted Rights Legend
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ware and technical data rights granted to
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puter Software Documentation).
Safety Notices
CAUTION
A CAUTION notice denotes a haz-
ard. It calls attention to an operat-
ing procedure, practice, or the likes
of that, if not correctly performed
or adhered to, could result in dam-
age to the product or loss of impor-
tant data. Do not proceed beyond a
CAUTION notice until the indicated
conditions are fully understood and
met.
WARNING
A WARNING notice denotes a
hazard. It calls attention to an
operating procedure, practice, or
the likes of that, if not correctly
performed or adhered to, could
result in personal injury or death.
Do not proceed beyond a WARN-
ING notice until the indicated
conditions are fully understood
and met.

U1271A/U1272A Service Guide III
Safety Symbols
The following symbols on the instrument and in the documentation
indicate precautions which must be taken to maintain safe operation of
the instrument.
Direct current (DC) Off (supply)
Alternating current (AC) On (supply)
Both direct and alternating current Caution, risk of electric shock
Three-phase alternating current Caution, risk of danger (refer to this manual
for specific Warning or Caution information)
Earth (ground) terminal Caution, hot surface
Protective conductor terminal Out position of a bi-stable push control
Frame or chassis terminal In position of a bi-stable push control
Equipotentiality Category III 1000 V overvoltage protection
Equipment protected throughout by
double insulation or reinforced
insulation
Category IV 600 V overvoltage protection
CAT III
1000 V
CAT IV
600 V

IV U1271A/U1272A Service Guide
Safety Considerations
Read the information below before using this multimeter. The descriptions
and instructions in this manual apply to the Agilent U1271A and U1272A
Handheld Digital Multimeters (hereafter referred to as the multimeter).
The model U1272A appears in all illustrations.
CAUTION
•Disconnect circuit power and discharge all high-voltage capacitors
before testing resistance, continuity, diodes, or capacitance.
•Use the proper terminals, function, and range for your
measurements.
•This device is for use at altitudes of up to 2,000 m.
•Never measure voltage when current measurement is selected.
•Always use the specified battery type.
WARNING
• Do not use the multimeter if it is damaged. Before you use the
multimeter, inspect the case. Look for cracks or missing plastic.
Pay particular attention to the insulation surrounding the
connectors.
• Inspect the test leads for damaged insulation or exposed metal.
Check the test leads for continuity. Replace damaged test leads
before you use the multimeter.
• Do not operate the multimeter around explosive gas, vapor, or wet
environments.
• Do not apply more than the rated voltage (as marked on the
multimeter) between terminals, or between terminal and earth
ground.
• Never use the multimeter in wet conditions or when there is
water on the surface. If the multimeter is wet, ensure that the
multimeter is dried only by trained personnel.
• Before use, verify the multimeter's operation by measuring a
known voltage.

U1271A/U1272A Service Guide V
WARNING
• When measuring current, turn off the circuit power before
connecting the multimeter in the circuit. Remember to place the
multimeter in series with the circuit.
• When servicing the multimeter, use only the specified
replacement parts.
• Use caution when working above 60 V DC, 30 V AC RMS, or 42.4 V
peak. Such voltages pose a shock hazard.
• Be aware of the presence of hazardous voltage before using the
Low Pass Filter (LPF) function for voltage measurement. Voltages
measured are usually greater than what indicated on the
multimeter as the voltages with higher frequencies have been
filtered through the LPF function.
• Do not use the ZLOW (low input impedance) function (U1272A
only) to measure voltages in circuits that could be damaged by
this function’s low input impedance of 2 kΩ.
• When using the probes, keep your fingers behind the finger
guards on the probes.
• Connect the common test lead before you connect the live test
lead. When you disconnect the leads, disconnect the live test lead
first.
• Remove the test leads from the multimeter before you open the
battery cover.
• Do not operate the multimeter with the battery cover or portions
of the cover removed or loosened.
• To avoid false readings, which may lead to possible electric shock
or personal injury, replace the battery as soon as the low battery
indicator appears and flashes.

VI U1271A/U1272A Service Guide
Environmental Conditions
This instrument is designed for indoor use and in an area with low
condensation. The table below shows the general environmental
requirements for this instrument.
Environmental conditions Requirements
Operating temperature Full accuracy from –20 °C to 55 °C
Operating humidity
Full accuracy up to 80% RH (relative
humidity) for temperature up to 30 °C,
decreasing linearly to 50% RH at 55 °C
Storage temperature –40 °C to 70 °C
Altitude Up to 2000 meters
Pollution degree Pollution degree II
NOTE
The U1271A/U1272A Handheld Digital Multimeter complies with the following
safety and EMC requirements:
•EN/IEC 61010-1:2001
•ANSI/UL 61010-1:2004
•CAN/CSA-C22.2 No. 61010-1-04
•Commercial limits compliance with EN61326-1

U1271A/U1272A Service Guide VII
Regulatory Markings
The CE mark is a registered trademark
of the European Community. This CE
mark shows that the product complies
with all the relevant European Legal
Directives.
The C-tick mark is a registered
trademark of the Spectrum
Management Agency of Australia. This
signifies compliance with
the Australia EMC Framework
regulations under the terms of the
Radio Communication Act of 1992.
ICES/NMB-001 indicates that this ISM
device complies with the Canadian
ICES-001.
Cet appareil ISM est confomre a la
norme NMB-001 du Canada.
This instrument complies with the
WEEE Directive (2002/96/EC) marking
requirement. This affixed product label
indicates that you must not discard
this electrical or electronic product in
domestic household waste.
The CSA mark is a registered
trademark of the Canadian Standards
Association.
This symbol indicates the time period
during which no hazardous or toxic
substance elements are expected to
leak or deteriorate during normal use.
Forty years is the expected useful life
of the product.

VIII U1271A/U1272A Service Guide
Waste Electrical and Electronic Equipment (WEEE) Directive 2002/96/EC
This instrument complies with the WEEE Directive (2002/96/EC) marking
requirement. This affixed product label indicates that you must not discard
this electrical or electronic product in domestic household waste.
Product Category:
With reference to the equipment types in the WEEE directive Annex 1, this
instrument is classified as a “Monitoring and Control Instrument” product.
The affixed product label is as shown below.
Do not dispose in domestic household waste.
To return this unwanted instrument, contact your nearest Agilent Service
Centre, or visit
www.agilent.com/environment/product
for more information.

U1271A/U1272A Service Guide IX
Declaration of Conformity (DoC)
The Declaration of Conformity (DoC) for this instrument is available on the
Agilent Web site. You can search the DoC by its product model or
description at the Web address below.
http://regulations.corporate.agilent.com/DoC/search.htm
NOTE
If you are unable to search for the respective DoC, please contact your
local Agilent representative.

X U1271A/U1272A Service Guide
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