Agilent Technologies U1242A User manual

Agilent Technologies
Agilent U1241A and
U1242A
Handheld Digital
Multimeters
User’s and Service Guide

II U1241A/U1242A User’s and Service Guide
Notices
© Agilent Technologies, Inc., 2007 – 2012
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
U1241-90003
Edition
Seventh Edition, May 4, 2012
Printed in Malaysia
Agilent Technologies, Inc.
3501 Stevens Creek Blvd.
Santa Clara, CA 95052 USA
Warranty
The material contained in this docu-
ment is provided “as is,” and is sub-
ject to being changed, without notice,
in future editions. Further, to the max-
imum extent permitted by applicable
law, Agilent disclaims all warranties,
either express or implied, with regard
to this manual and any information
contained herein, including but not
limited to the implied warranties of
merchantability and fitness for a par-
ticular purpose. Agilent shall not be
liable for errors or for incidental or
consequential damages in connec-
tion with the furnishing, use, or per-
formance of this document or of any
information contained herein. Should
Agilent 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 sep-
arate agreement shall control.
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The hardware and/or software described in
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dance with the terms of such license.
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ware and technical data rights granted to
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Data) and 12.212 (Computer Software) and,
for the Department of Defense, DFARS
252.227-7015 (Technical Data - Commercial
Items) and DFARS 227.7202-3 (Rights in
Commercial Computer Software or Com-
puter Software Documentation).
Safety Notices
CAUTION
A CAUTION notice denotes a haz-
ard. It calls attention to an operat-
ing procedure, practice, or the like
that, if not correctly performed or
adhered to, could result in damage
to the product or loss of important
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 like that, if not correctly per-
formed or adhered to, could result
in personal injury or death. Do not
proceed beyond a WARNING
notice until the indicated condi-
tions are fully understood and
met.

U1241A/U1242A User’s and 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 U1241A/U1242A User’s and Service Guide
General Safety Information
The following general safety precautions must be observed during all phases of
operation, service and repair of this instrument. Failure to comply with these
precautions or with specific warnings elsewhere in this manual violates safety
standards of design, manufacture and intended use of the instrument. Agilent
Technologies assumes no liability for the customer’s failure to comply with these
requirements.
WARNING
•Observe all markings on the instrument before connecting any
wiring to the instrument.
• When working above 60 VDC, 30 VAC RMS or 42 V peak, exercise
caution – such range pose a shock hazard.
• Do not measure more than the rated voltage (as marked on the
meter) between terminals, or between terminal and earth ground.
• Double-check the meter’s operation by measuring a known voltage.
• For current measurement, turn off circuit power before connecting
the meter to the circuit. Always place the meter in series with the
circuit.
• When connecting probes, always connect the common test probe
first. When disconnecting probes, always disconnect the live test
probe first.
• Detach test probes from the meter before you open the battery cover.
• Do not use the meter with the battery cover or part of the cover
removed or loose.
• Replace the battery as soon as the low battery indicator flashes
on screen. This is to avoid false readings, which may lead to possible
electric shock or personal injury.
• Do not operate the product in an explosive atmosphere or in the
presence of flammable gases or fumes.
• Inspect the case for cracks or missing plastic. Pay extra attention to
the insulation surrounding the connectors. Do not use the meter if it
is damaged.
• Inspect the test probes for damaged insulation or exposed metal,
and check for continuity. Do not use the test probe if it is damaged.

U1241A/U1242A User’s and Service Guide V
WARNING
• Do not use repaired fuses or short-circuited fuse-holders. For
continued protection against fire, replace the line fuses only with
fuses of the same voltage and current rating and recommended type.
• Do not service or perform adjustments alone. Under certain
condition, hazardous voltages may exist, even with the equipment
switched off. To avoid dangerous electric shock, service personnel
must not attempt internal service or adjustment unless another
person, capable of rendering resuscitation or first aid, is present.
• Do not substitute parts or modify equipment to avoid the danger of
introducing additional hazards. Return the product to Agilent
Technologies Sales and Service Office for service and repair to
ensure the safety features are maintained
• Do not operate damaged equipment as the safety protection features
built into this product may have been impaired, either through
physical damage, excessive moisture, or any other reason. Remove
power and do not use the product until safe operation can be verified
by service-trained personnel. If necessary, return the product to
Agilent Technologies Sales and Service Office for service and repair
to ensure the safety features are maintained.
CAUTION
• Turn off circuit power and discharge all high-voltage capacitors in the
circuit before you perform resistance, continuity, diodes, or
capacitance tests.
• Use the correct terminals, function, and range for your measurements.
• Never measure voltage when current measurement is selected.
• Ensure proper insertion of battery in the meter, and follow the correct
polarity.

VI U1241A/U1242A User’s and Service Guide
Environment Conditions
This instrument is designed for indoor in the area with low condensation and use
with standard or compatible test probes. Table 1 shows general environment
requirements.
Table 1 Environment Requirements
Environment Conditions Requirements
Operating environment Full accuracy at –10 °C to 55 °C
Operating relative humidity Full accuracy up to 80% RH for
temperature up to 30 °C, decreasing
linearly to 50% RH at 55 °C
Storage environment –20 °C to 70 °C
Altitude 0 – 2000 meters per IEC 61010-1 2nd
Edition CAT III, 1000 V/ CAT IV, 600 V
Pollution Degree Pollution Degree II
CAUTION
The Agilent U1241A and U1242A are safety-certified in compliance with
the following safety and EMC requirements:
• IEC 61010-1:2001 / EN61010-1:2001
• USA: UL 61010-1:2004
• Canada: CSA C22.2 No. 61010-1:2004
• IEC 61326-1:2005/ EN 61326-1:2006
• Canada: ICES-001:2004
• Australia/New Zealand: AS/NZS CISPR11:2004

U1241A/U1242A User’s and 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 Canadian
ICES-001.
This instrument complies with the WEEE
Directive (2002/96/EC) marking
requirement. This affixed product label
indicates that you must not discard this
electrical/electronic product in domestic
household waste.
The CSA mark is a registered trademark
of the Canadian Standards Association.

VIII U1241A/U1242A User’s and 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/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 shown as below:
Do not dispose in domestic household waste
To return this unwanted instrument, contact your nearest Agilent office, or visit:
www.agilent.com/environment/product
for more information.

U1241A/U1242A User’s and Service Guide IX
In This Guide…
1Getting Started Chapter 1 introduces key features and steps to get started
with a U1241A or U1242A handheld digital multimeter. This chapter also guides
you through the basics of the front panel operations.
2Features and Functions Chapter 2 contains the information on how to set up
connections to perform meter measurements. It also describes the features and
functions that are available in the U1241A and U1242A handheld digital
multimeters in step-by-step instructions.
3Default Setting Configurations Chapter 3 describes on how to change and
configure the default setting of the U1241A and U1242A handheld digital
multimeters including data logging and other setting features
4Service and Maintenance Chapter 4 provides the information on the
warranty, services, maintenance procedures and troubleshooting hints to solve
general problems that you may encounter with the meter.
5Performance Tests and Calibration Chapter 5 contains the procedures of
the performance verification tests and calibration adjustments.
6Specifications and Characteristics Chapter 6 lists the specifications and
characteristics of the U1241A and U1242A handheld digital multimeters.

X U1241A/U1242A User’s and Service Guide
Declaration of Conformity (DoC)
The Declaration of Conformity (DoC) for this instrument is available on the Web
site. You can search the DoC by its product model or description.
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.

U1241A/U1242A User’s and Service Guide XI
Contents
1 Getting Started
Introduction 2
Checking the Shipping Contents 3
The Front Panel at a Glance 4
Adjusting Tilt Stand 4
The Annunciator at a Glance 5
Analog Bar Graph 6
The Keypad and Rotary Switch at a Glance 6
The Input Terminal at a Glance 8
2 Features and Functions
Measuring Voltage 10
Measuring Current (> 440 mA) 10
Measuring Current (< 440 mA) 11
Measuring % Scale of 4 – 20 mA 11
Measuring Frequency 12
Measuring Resistance and Testing Continuity 12
Testin g D i o d e s 13
Measuring Capacitance 14
Measuring Temperature 14
Measuring Harmonic Ratio (U1242A) 16
Using Switch Counter 16
MINMAX Recording 18
Data Hold (Trigger Hold) 18

XII U1241A/U1242A User’s and Service Guide
Refresh Hold 19
NULL (Relative) 19
Data Logging (U1242A) 20
Manual Logging 21
Interval Logging 21
Reviewing Logged Data 22
Removing Logged Data 22
Scanning Temperature Measurement (U1242A) 23
Checking Battery Capacity 23
Alerts and Warning During Measurement 24
Overload Alert 24
Input-A Warning Alert 24
Input-mA Warning Alert 24
3 Default Setting Configurations
Setting Configurations 26
4 Service and Maintenance
General Maintenance 30
Battery Replacement 30
Fuse Replacement 31
Troubleshooting 33
Returning Instrument for Service 34
5 Performance Tests and Calibration
Calibration Overview 36
Closed-case Electronic Calibration 36
Calibration Interval 36
Adjustment is Recommended 37

U1241A/U1242A User’s and Service Guide XIII
Recommended Test Equipment 38
Basic Operating Test 39
Backlight Test 39
Testing the Display 39
Input-A Terminal Test 40
Input-mA Terminal Alert Test 40
Calibration Process 40
Test Considerations 41
Input Connections 42
Performance Verification Tests 42
Calibration Security 46
Unsecuring the Meter for Calibration 46
Using the Front Panel for Adjustments 48
Adjustment Considerations 49
Valid Adjustment Input Values 50
Calibration Adjustments 51
Exiting Adjustment Mode 55
Calibration Count 56
Calibration Errors 56
6 Specifications and Characteristics
DC Specifications 58
AC Specifications 59
Resistance Specifications 60
Diode Check/Audible Continuity Test Specifications 60
Temperature Specifications 61
Capacitance Specifications 62

XIV U1241A/U1242A User’s and Service Guide
Harmonic Ratio Specifications 62
Frequency Specifications 63
Frequency Sensitivity During Voltage Measurement[2] 63
Frequency Sensitivity During Current Measurement[3] 63
Operating Specifications 64
General Characteristics 65

1
Agilent Technologies
U1241A and U1242A Handheld Digital Multimeters
User’s and Service Guide
1
Getting Started
Introduction 2
Checking the Shipping Contents 3
The Front Panel at a Glance 4
Adjusting Tilt Stand 4
The Annunciator at a Glance 5
The Keypad and Rotary Switch at a Glance 6
The Input Terminal at a Glance 8
This chapter introduces key features and steps to get started with a
U1241A or U1242A handheld digital multimeter. This chapter also guides
you through the basics of the front panel operations.

2 U1241A/U1242A User’s and Service Guide
1GettingStarted
Introduction
The handheld digital multimeters’ key features are:
•DC, AC voltage and current measurements.
•True- RMS measurement for both AC voltage and current
•Harmonic ratio for power quality of sine wave (for U1242A)
•Switch counter for detecting the bounce of switch
•Ambient temperature display with each measurement
•SCAN temperature measurement for T1, T2 and T1–T2 (for U1242A)
•Resistance measurement up to 100 MΩ
•Diode and audible continuity tests
•Capacitance measurement up to 10mF
•The % scale readout for 4–20 mA or 0–20 mA measurement
•Temperature test with selectable 0 °C compensation (without ambient
temperature compensation).
•K- type (for U1241A) and J/K- types temperature measurement (for
U1242A)
•MINMAX Recording for minimum, maximum and average readings
•Data Hold with manual or auto trigger
•Null/Relative function
•Auto or manual data logging memories (for U1242A)
•Battery capacity indicator
•Adjustable brightness level of blue LED backlight display
•Closed case calibration
•10,000 count precision true RMS digital multimeter, designed to meet
EN/IEC 61010- 1:2001 Category III 1000 V/ Category IV 600 V
Overvoltage Protection, Pollution Degree II standards

Getting Started 1
U1241A/U1242A User’s and Service Guide 3
Checking the Shipping Contents
Verify that you have received the following items for the standard shipped
items or optional accessories that you may have ordered. If any of the
above item missing, or any mechanical damage and defect on the meter,
notify your nearest Agilent Technologies Sales Office.
Table 1- 1 List of standard items and optional accessories
Type Model ID Items
Standard U1241A or U1242A handheld digital multimeter
Four 1.5 V AAA alkaline batteries
Te s t Le ad s
Quick Start Guide
Product Reference CD
Certificate of Calibration
Optional U1162A Alligator clips
U1163A SMT Grabbers
U1164A Fine tip test probe
U1181A Immersion probe type-K
U1182A Industrial surface probe
U1183A Air probe
U1184A Temperature probe adapter
U1185A Thermocouple (J-type) probe and adapter
U1186A Thermocouple (K-type) probe and adapter
U1583A AC current clamp

4 U1241A/U1242A User’s and Service Guide
1GettingStarted
The Front Panel at a Glance
Figure 1-1 Front panel of a U1241A and U1242A handheld digital multimeters
Adjusting Tilt Stand
Figure 1-2 Tilt stand positions
Annunciator
Keypad
Rotary Switch
Input Terminal
Pull the tilt stand outwards to its
maximum reach (approximately 60°)
Tilt stand at 60°Tilt stand at 30°
Bend the tip of the stand

Getting Started 1
U1241A/U1242A User’s and Service Guide 5
The Annunciator at a Glance
To view the full display, press and hold while turning the rotary
switch from OFF to any non- OFF position. Press any key to resume
normal functionality mode.
Figure 1-3 Annunciator display of a U1242A handheld digital multimeter
Table 1- 2 Descriptions of each annunciator
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
21
20
22
23
No. Descriptions No. Descriptions
121-segment analog bar graph display 12 MINMAX Recording mode
2Capacitor discharge indicator 13 Harmonic Ratio mode (for U1242A)
3Cold junction of ambient temperature disabled 14 Data logging mode (for U1242A)
4Audible continuity for resistance and diode function 15 Data logging View mode (for U1242A)
5Primary display 16 Auto or manual for data logging mode and datalog
viewing mode
6AC or DC measurement mode 17 Secondary display (temperature display)
7Auto range 18 Null math function
8Diode / Audible continuity 19 Thermocouple type for temperature measurement
9T1, T2 and T1 – T2 temperature measurements scan
(for U1242A)
20 Primary measurement units
21 Measurement range
10 Data hold 22 Low battery indicator
11 T1, T2* or T1 – T2* temperature measurements 23 Auto power off indicator
*T2 temperature measurement and delta (T1 – T2) are only available for U1242A.

6 U1241A/U1242A User’s and Service Guide
1GettingStarted
Analog Bar Graph
When frequency is indicated on the primary display during voltage or cur-
rent measurement, the bar graph represents the voltage or current value.
When 4–20 mA% scale or 0–20 mA% scale is indicated on the primary dis-
play, the bar graph represents the current value. Each segment represents
500 or 50 counts depending on the range indicated on the peak bar graph.
Table 1- 3 Bar graph counts
The Keypad and Rotary Switch at a Glance
Figure 1-4 Keypad and rotary switch of a U1242A handheld digital multimeter
Range Counts / Segment Function
50 Diode
500 V, A, Ω,