Keysight U1242C, U1241C User Manual

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Keysight U1241C/U1242C Handheld Digital Multimeter

User’s Guide

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Notices

CAUTION

WARNING

duced in any form or by any means (including electronic storage and retrieval or translation into a foreign language) without prior agreement and written consent from Keysight Technologies as governed by United States and international copyright laws.

Trademark

Bluetooth and the Bluetooth logos are trademarks owned by Bluetooth SIG, Inc., U.S.A. and licensed to Keysight Technologies.

Manual Part Number

U1241-90105

Edition

Edition 3, June 23, 2017

Printed in:

Printed in Malaysia

Published by:

Keysight Technologies Bayan Lepas Free Industrial Zone, 11900 Penang, Malaysia

Technology Licenses

The hardware and/or software described in this document are furnished under a license and may be used or copied only in accordance with the terms of such license.

Declaration of Conformity

Declarations of Conformity for this product and for other Keysight products may be downloaded from the Web. Go to http://www.keysight.com/

go/conformity. You can then search by

product number to find the latest Declaration of Conformity.

U.S. Government Rights

The Software is “commercial computer software,” as defined by Federal Acquisition Regulation (“FAR”) 2.101. Pursuant to FAR 12.212 and 27.405-3 and Department of Defense FAR Supplement (“DFARS”) 227.7202, the U.S. government acquires commercial computer software under the same terms by which the software is customarily provided to the public. Accordingly, Keysight provides the Software to U.S. government customers under its standard commercial license, which is embodied in its End User License Agreement (EULA), a copy of which can be found at http://www.keysight.com/

find/sweula. The license set forth in the

EULA represents the exclusive authority by which the U.S. government may use, modify, distribute, or disclose the Software. The EULA and the license set forth therein, does not require or permit, among other things, that Keysight: (1) Furnish technical information related to commercial computer software or commercial computer software documentation that is not customarily provided to the public; or (2) Relinquish to, or otherwise provide, the government rights in excess of these rights customarily provided to the public to use, mod ify, reproduce, release, perform, display, or disclose commercial computer software or commercial computer software documentation. No additional government requirements beyond those set forth in the EULA shall apply, except to the extent that those terms, rights, or licenses are explicitly required from all providers of commercial computer software pursuant to the FAR and the DFARS and are set forth specifically in writing elsewhere in the EULA. Keysight shall be under no obligation to update, revise or otherwise modify the Software. With respect to any technical data as defined by FAR 2.101, pursuant to FAR

12.211 and 27.404.2 and DFARS

227.7102, the U.S. government acquires no greater than Limited Rights as defined in FAR 27.401 or DFAR

227.7103-5 (c), as applicable in any technical data.

Warranty

THE MATERIAL CONTAINED IN THIS DOCUMENT IS PROVIDED “AS IS,” AND IS SUBJECT TO BEING CHANGED, WITHOUT NOTICE, IN FUTURE EDITIONS. FURTHER, TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, KEYSIGHT 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 PARTICULAR PURPOSE. KEYSIGHT 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 KEYSIGHT 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.

Safety Information

A CAUTION notice denotes a hazard. It calls attention to an operating 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.

A WARNING notice denotes a hazard. It calls attention to an operating procedure, practice, or the like that, if not correctly performed or adhered to, could result in personal injury or death. Do not proceed beyond a WARNING notice until the indicated conditions are fully understood and met.

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Safety Symbols

The following symbols on the instrument and in the documentation indicate precautions that must be taken to maintain safe operation of the instrument.

Caution, risk of danger (refer to this manual for specific Warning or Caution information)

Earth (ground) terminal

CAT IV

600 V

Equipment protected throughout by double insulation or reinforced insulation

Category IV 600 V overvoltage protection

CAT III

1000 V

Category III 1000 V overvoltage protection

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Safety Considerations

WARNING

Read the information below before using this instrument.

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 for design, manufacture, and intended use of the instrument. Keysight Technologies assumes no liability for the customer’s failure to comply with these requirements.

– Do not exceed any of the measurement limits defined in the specifications

to avoid instrument damage and the risk of electric shock.

– 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.

– 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.

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WARNING

– When using the probes, keep your fingers behind the finger guards on the

CAUTION

probes.

– Only use the probe assemblies with RATED MEASUREMENT CATEGORY III

or IV for MAINS measurements.

– 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.

– Remove the test leads from the measuring source or target before

changing the rotary switch position.

– 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.

– Comply with local and national safety requirements when working in

hazardous areas, and use proper protection equipment.

– Disconnect circuit power and discharge all high-voltage capacitors

before testing resistance, continuity, diodes, or capacitance.

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– Use the proper terminals, function, and range for your measurements.

– This multimeter is for use at altitudes of up to 3000 m.

– Never measure voltage when the current measurement is selected.

– Always use the specified battery type. The power for the multimeter is

supplied with four 1.5 V AAA batteries. Observe the correct polarity markings before you insert the batteries to ensure proper insertion of the batteries in the multimeter.

– To prevent damage to the multimeter from battery leakage:

– Always remove dead batteries immediately.

– Always remove the batteries and store them separately if the multimeter

is not going to be used for a long period.

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Measurement Category

The U1241C/U1242C has safety ratings of CAT III 1000 V and CAT IV 600 V.

Measurement CAT I Measurements performed on circuits not directly connected to the AC mains. Examples are measurements on circuits not derived from the AC mains and specially protected (internal) mains-derived circuits.

Measurement CAT II Measurements performed on circuits directly connected to a low-voltage installation. Examples are measurements on household appliances, portable tools, and similar equipment.

Measurement CAT III Measurements performed in the building installation. Examples are measurements on distribution boards, circuit-breakers, wiring, including cables, bus-bars, junction boxes, switches, socket outlets in the fixed installation, and equipment for industrial use, and some other equipment including stationary motors with permanent connection to the fixed installation.

Measurement CAT IV Measurements performed at the source of the low-voltage installation. Examples are electricity meters and measurements on primary overcurrent protection devices and ripple control units.

Use only the product rated Measurement Category on the location of measuring circuits as identified below.

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Environmental Conditions

The U1241C/U1242C is designed for indoor use and in an area with low condensation. The table below shows the general environmental requirements for this instrument.

Environmental condition Requirement

Temperature

Humidity

Altitude Up to 3000 m

Pollution degree 2

Operating condition – –20 °C to 55 °C, 0 to 80% RH Storage condition – –40 °C to 70 °C, 0 to 80% RH (without batteries)

Up to 80% RH for temperature of up to 30 °C decreasing linearly to 50% RH at 55 °C

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Safety and Regulatory Information

The U1241C/U1242C complies with the following safety and Electromagnetic Compatibility (EMC) compliances:

Safety compliance

– IEC/EN 61010-1

– IEC/EN 61010-2-033

– Canada: CAN/CSA-C22.2 No. 61010-1, CAN/CSA-C22.2 No. 61010-033

– USA: ANSI/UL Std. No. 61010-1, ANSI/UL Std. No. 61010-033

EMC compliance

– IEC 61326-1/EN 61326-1

– Canada: ICES/NMB-001

– Australia/New Zealand: AS/NZS CISPR 11

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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.

ICES/NMB-001 indicates that this ISM device complies with the Canadian ICES-001.

Cet appareil ISM est conforme a la norme NMB-001 du Canada.

The CSA mark is a registered trademark of the Canadian Standards Association.

The RCM 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.

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.

This symbol is a South Korean Class A EMC Declaration. This is a Class A instrument suitable for professional use and in electromagnetic environment outside of the home.

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.

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Waste Electrical and Electronic Equipment (WEEE) Directive 2002/ 96/EC

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 Keysight Service Center, or visit http://about.keysight.com/en/companyinfo/environment/takeback.shtml for more information.

Sales and Technical Support

To contact Keysight for sales and technical support, refer to the support links on the following Keysight websites:

– www.keysight.com/find/U1241C or www.keysight.com/find/U1242C

(product-specific information and support, software and documentation updates)

– www.keysight.com/find/assist

(worldwide contact information for repair and service)

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Safety Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

Safety Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

Measurement Category . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

Environmental Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

Safety and Regulatory Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

Regulatory Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

Waste Electrical and Electronic Equipment (WEEE) Directive 2002/96/

EC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

Product category . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

Sales and Technical Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

1Introduction

About This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Documentation map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22

Safety notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22

Preparing Your Multimeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23

Check the shipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23

Install the batteries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Turn on your multimeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26

Automatic power off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26

Enabling the backlight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27

Selecting the range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27

Alerts and warnings during measurement . . . . . . . . . . . . . . . . . . . . 28

Adjusting the tilt stand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30

Remote communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31

Power-on options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34

Your Multimeter in Brief . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35

Rotary switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37

Keypad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Display screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42

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Input terminals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Cleaning Your Multimeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

2Making Measurements

Crest Factor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

Measuring AC Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Measuring Harmonic Ratio (U1242C only) . . . . . . . . . . . . . . . . . . . . . . 55

Measuring DC Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Measuring AC or DC mV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

Using Z

for Voltage Measurements (U1242C only) . . . . . . . . . . . . 61

LOW

Measuring Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Testing for Continuity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

Testing Diodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

Measuring Capacitance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

Measuring Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Using the low pass frequency filter function for frequency

measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Measuring Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

Scanning temperature measurements (U1242C only) . . . . . . . . . . . 84

Measuring AC or DC Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

% Scale of 4-20 mA or 0-20 mA . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

3 Multimeter Features

Detecting AC Voltage Presence (Vsense) (U1242C only) . . . . . . . . . . . 96

Making Relative Measurements (Null) . . . . . . . . . . . . . . . . . . . . . . . . . . 98

Capturing Maximum and Minimum Values (MaxMin) . . . . . . . . . . . . . 100

Freezing the Display (TrigHold and AutoHold) . . . . . . . . . . . . . . . . . . 102

TrigHold operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

AutoHold operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

Recording Measurement Data (Data Logging) . . . . . . . . . . . . . . . . . . 104

Performing manual logs (HAnd) . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

Performing interval logs (AUto) . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

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Performing event logs (triG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .107

Performing export logs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .109

Reviewing Previously Recorded Data (View) . . . . . . . . . . . . . . . . . . . .110

Sanitizing the log memories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111

4 Multimeter Setup Options

Using the Setup Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114

Editing numerical values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115

Setup Menu Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116

Setup Menu Items . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119

Changing the variation count . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119

Enabling smooth mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .120

Changing the auto power off (APO), backlight, and flashlight

timeouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .121

Changing the backlight and flashlight brightness . . . . . . . . . . . . .123

Changing the recording option . . . . . . . . . . . . . . . . . . . . . . . . . . . .124

Changing the sample interval duration . . . . . . . . . . . . . . . . . . . . . .125

Changing the thermocouple type or setting the mV

measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126

Changing the temperature unit . . . . . . . . . . . . . . . . . . . . . . . . . . . .128

Changing the beep frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . .129

Changing the startup sound . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .130

Changing the continuity type . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131

Changing the continuity alert type . . . . . . . . . . . . . . . . . . . . . . . . .132

Changing the battery type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .133

Resetting the multimeter’s setup options . . . . . . . . . . . . . . . . . . . .135

Setting the data refresh rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136

Setting the input impedance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .137

Enabling the DC path filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138

Changing the % scale range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139

5 Characteristics and Specifications

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List of Figures

Figure 1-1 Start-up display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26

Figure 1-2 Example of wrong terminal input . . . . . . . . . . . . . . . . .29

Figure 1-3 LEAd input warning display . . . . . . . . . . . . . . . . . . . . .30

Figure 1-4 Tilt-stand adjustment and IR-USB cable connection .30

Figure 1-5 Bluetooth adapter connection . . . . . . . . . . . . . . . . . . .32

Figure 1-6 Handheld Meter Logger software . . . . . . . . . . . . . . . .33

Figure 1-7 Front panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35

Figure 1-8 Rear panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36

Figure 1-9 Rotary switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37

Figure 1-10 Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39

Figure 1-11 Display screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42

Figure 1-12 Connector terminals . . . . . . . . . . . . . . . . . . . . . . . . . . .47

Figure 2-1 AC voltage display . . . . . . . . . . . . . . . . . . . . . . . . . . . .53

Figure 2-2 Measuring AC voltage . . . . . . . . . . . . . . . . . . . . . . . . .54

Figure 2-3 Harmonic ratio measurement . . . . . . . . . . . . . . . . . . .56

Figure 2-4 DC voltage display . . . . . . . . . . . . . . . . . . . . . . . . . . . .57

Figure 2-5 Measuring DC voltage . . . . . . . . . . . . . . . . . . . . . . . . .58

Figure 2-6 DC mV display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60

Figure 2-7 Z

Figure 2-8 Resistance display . . . . . . . . . . . . . . . . . . . . . . . . . . . .63

Figure 2-9 Measuring resistance . . . . . . . . . . . . . . . . . . . . . . . . . .64

Figure 2-10 Testing for continuity . . . . . . . . . . . . . . . . . . . . . . . . . .68

Figure 2-11 Diode display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69

Figure 2-12 Open diode display . . . . . . . . . . . . . . . . . . . . . . . . . . . .70

Figure 2-13 Testing a forward bias diode . . . . . . . . . . . . . . . . . . . .71

Figure 2-14 Testing a reverse bias diode . . . . . . . . . . . . . . . . . . . .72

Figure 2-15 Capacitance display . . . . . . . . . . . . . . . . . . . . . . . . . . .73

Figure 2-16 Measuring capacitance . . . . . . . . . . . . . . . . . . . . . . . .74

Figure 2-17 Frequency measurement . . . . . . . . . . . . . . . . . . . . . . .76

Figure 2-18 Frequency display . . . . . . . . . . . . . . . . . . . . . . . . . . . .77

Figure 2-19 Low pass frequency filter function with averaging

Figure 2-20 T1 temperature display . . . . . . . . . . . . . . . . . . . . . . . .80

Figure 2-21 Measuring surface temperature (T1) . . . . . . . . . . . . . .82

display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62

LOW

sense . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78

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Figure 2-22 Temperature measurement without ambient

compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

Figure 2-23 Scan mode for temperature measurements . . . . . . . . 84

Figure 2-24 DC current display . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

Figure 2-25 Measuring DC current . . . . . . . . . . . . . . . . . . . . . . . . . 88

Figure 2-26 Measuring AC current . . . . . . . . . . . . . . . . . . . . . . . . . 89

Figure 2-27 Current measurement setup . . . . . . . . . . . . . . . . . . . . 90

Figure 2-28 4-20 mA % scale display . . . . . . . . . . . . . . . . . . . . . . . 92

Figure 2-29 Measuring DC current using the 4-20 mA % scale . . 93

Figure 3-1 High Vsense sensitivity display . . . . . . . . . . . . . . . . . . 97

Figure 3-2 Low Vsense sensitivity display . . . . . . . . . . . . . . . . . . . 97

Figure 3-3 Null display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

Figure 3-4 Null operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

Figure 3-5 MaxMin display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

Figure 3-6 Manual log display . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

Figure 3-7 Interval log display . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

Figure 3-8 Event log display . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

Figure 3-9 Export log display . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

Figure 3-10 View display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

Figure 3-11 Empty view display . . . . . . . . . . . . . . . . . . . . . . . . . . 110

Figure 4-1 AH display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

Figure 4-2 tiME display - Smooth . . . . . . . . . . . . . . . . . . . . . . . . 120

Figure 4-3 AoFF display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

Figure 4-4 bLit display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

Figure 4-5 tLit display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

Figure 4-6 b-L display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

Figure 4-7 t-L display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124

Figure 4-8 tYPE display - data logging . . . . . . . . . . . . . . . . . . . . 125

Figure 4-9 tiME display - data logging . . . . . . . . . . . . . . . . . . . . 126

Figure 4-10 CoUP display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

Figure 4-11 Unit display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

Figure 4-12 bEEP display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

Figure 4-13 SoUn display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131

Figure 4-14 tYPE display - continuity . . . . . . . . . . . . . . . . . . . . . . 132

Figure 4-15 Horn display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

Figure 4-16 bAt display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134

Figure 4-17 rSt display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

16 Keysight U1241C/U1242C User’s Guide

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Figure 4-18 UPd display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136

Figure 4-19 inPU mV display . . . . . . . . . . . . . . . . . . . . . . . . . . . . .137

Figure 4-20 LPF display - DC . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139

Figure 4-21 PErC display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .140

Keysight U1241C/U1242C User’s Guide 17

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THIS PAGE HAS BEEN INTENTIONALLY LEFT BLANK.

18 Keysight U1241C/U1242C User’s Guide

Page 19

List of Tables

Table 1-1 Battery level indicator . . . . . . . . . . . . . . . . . . . . . . . . .25

Table 1-2 Power-on options . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34

Table 1-3 Front panel parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35

Table 1-4 Rear panel parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36

Table 1-5 Rotary switch functions . . . . . . . . . . . . . . . . . . . . . . . .37

Table 1-6 Keypad functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39

Table 1-7 General annunciators . . . . . . . . . . . . . . . . . . . . . . . . . .42

Table 1-8 Measurement units display . . . . . . . . . . . . . . . . . . . . .45

Table 1-9 Analog bar graph display . . . . . . . . . . . . . . . . . . . . . . .46

Table 1-10 Terminal connections for different measurement

functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48

Table 2-1 Rotary switch position allowing AC voltage

measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53

Table 2-2 Rotary switch position allowing harmonic ratio

measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55

Table 2-3 Rotary switch position allowing DC voltage

measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57

Table 2-4 Rotary switch position allowing AC or DC mV

measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59

Table 2-5 Rotary switch position allowing Z Table 2-6 Rotary switch position allowing resistance

measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63

Table 2-7 Rotary switch position allowing continuity tests . . . . .66

Table 2-8 Threshold resistance values . . . . . . . . . . . . . . . . . . . . .67

Table 2-9 Rotary switch position allowing diode tests . . . . . . . . 69

Table 2-10 Rotary switch position allowing capacitance

measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73

Table 2-11 Rotary switch positions allowing frequency

measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75

Table 2-12 Rotary switch position allowing temperature

measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79

Table 2-13 Rotary switch positions allowing current

measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86

Table 2-14 Rotary switch positions allowing current

measurements 61

LOW

Keysight U1241C/U1242C User’s Guide 19

Page 20

measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

Table 2-15 % scale measurement range . . . . . . . . . . . . . . . . . . . . 92

Table 3-1 Data logging maximum capacity . . . . . . . . . . . . . . . . 104

Table 3-2 Event log trigger conditions . . . . . . . . . . . . . . . . . . . 107

Table 4-1 Setup menu key functions . . . . . . . . . . . . . . . . . . . . . 114

Table 4-2 Setup menu item descriptions . . . . . . . . . . . . . . . . . 116

Table 4-3 Typical characteristics of the DC filter . . . . . . . . . . . 138

20 Keysight U1241C/U1242C User’s Guide

Page 21

Keysight U1241C/U1242C Handheld Digital Multimeter

NOTE

User’s Guide

1 Introduction

About This Manual 22 Preparing Your Multimeter 23 Your Multimeter in Brief 35 Cleaning Your Multimeter 49

This chapter lists the package contents for this multimeter, and it teaches you how to set up your multimeter for the first time. An introduction to all the features of the multimeter is also given. This introduction does not cover all of the capabilities of the multimeter but gives basic examples to help you perform basic operations on your multimeter.

The model U1242C appears in all illustrations in this manual.

Page 22

1Introduction

CAUTION

WARNING

About This Manual

Documentation map

The following manuals and software are available for your multimeter. For the latest version, visit our website at http://www.keysight.com/find/hhTechLib for the latest version.

Check the manual edition on the first page of each manual.

User’s Guide. This manual.

Quick Start Guide. Printed copy for outdoor use, included with shipment.

Service Guide. Downloadable from http://www.keysight.com/find/hhTechLib.

Keysight Handheld Meter Logger Software.

Downloadable from http://www.keysight.com/find/hhmeterlogger.

Safety notes

The following safety notes are used throughout this manual. Familiarize yourself with each of the notes and its meaning before operating your multimeter. More pertinent safety notes for using this product are located under the Safety Symbols section.

22 Keysight U1241C/U1242C User’s Guide

Page 23

Preparing Your Multimeter

Check the shipment

When you receive your multimeter, check the shipment according to the following procedure.

1 Inspect the shipping container for damage. Signs of damage may include a

dented or torn shipping container or cushioning material that indicates signs of unusual stress or compacting. Save the packaging material in case the multimeter needs to be returned.

2 Carefully remove the contents from the shipping container, and verify that the

standard accessories and your ordered options are included in the shipment according to the standard shipped items list found in the printed copy of the U1241C/U1242C Quick Start Guide.

3 For any question or problems, refer to the Keysight contact numbers at

www.keysight.com/find/assist.

Introduction 1

Keysight U1241C/U1242C User’s Guide 23

Page 24

1Introduction

CAUTION

Install the batteries

Your multimeter is powered by four 1.5 V AAA batteries (included with the shipment). When you receive your multimeter, the batteries are not installed.

Use the following procedure to install the batteries.

Before you proceed with the battery installation, remove all cable connections to the terminals and ensure that the rotary switch is at the OFF position. Use only the batteries provided with your multimeter.

1 Lift the tilt stand as shown on the right.

2 Loosen the two screws with a suitable Phillips

screwdriver as shown on the right.

3 Lift and remove the battery cover as shown on the

left.

4 Lift the inner cover to access the battery

compartment.

24 Keysight U1241C/U1242C User’s Guide

Page 25

Introduction 1

NOTE

WARNING

5 Observe the proper battery polarity. The terminal

ends of each battery are indicated inside the battery compartment. Insert four 1.5 V AAA batteries.

6 Ensure that the inner cover is positioned properly.

7 Replace the battery cover back in its original

position and tighten the screws.

The battery level indicator at the lower left corner of the display indicates the relative condition of the batteries. Table 1-1 describes the various battery levels the indicator represents.

Table 1-1 Battery level indicator

Battery capacity

Indication

Primary battery

(4.2 V to 6 V)

Secondary battery (rechargeable)

(4.5 V to 5.4 V)

Full capacity

2/3 capacity

Keysight U1241C/U1242C User’s Guide 25

1/3 capacity

(Flashing periodically)

Almost empty

When the battery voltage is < 3.8 V, the multimeter will shut down automatically regardless of whether the auto power off function has been disabled or not.

To avoid false readings, which could lead to possible electric shock or personal injury, replace the battery as soon as the low battery indicator appears. Do not discharge the battery by shorting the battery or reversing the battery polarity in any of the subjects.

Page 26

1Introduction

CAUTION

Firmware version

Model number

To avoid damage from battery leakage:

– Always remove dead batteries immediately.

– Always remove the batteries and store them separately if the multimeter

is not going to be used for a long period.

Turn on your multimeter

To power ON your multimeter, turn the rotary switch to any position other than

briefly on the primary display and secondary display respectively.

. The model number and firmware version of your multimeter will be shown

Figure 1-1 Start-up display

To power OFF your multimeter, turn the rotary switch to the position.

Automatic power off

Your multimeter automatically turns off after 15 minutes (default) if:

– the rotary switch is not moved, or

– a key is not pressed, or

– dynamic recording mode is disabled.

26 Keysight U1241C/U1242C User’s Guide

Page 27

To turn the multimeter back on after it is powered off automatically:

Range

Auto

Range

Auto

NOTE

Range

Auto

Range

Auto

– turn the rotary switch to the position and then turn it to any ON position,

– press any key, or

– move the rotary switch.

Enabling the backlight

If viewing the display becomes difficult in low-light conditions, press to activate the backlight of the LCD and keypad.

To conserve battery life, a user-adjustable timeout controls how long the backlight stays on. The default timeout is 15 seconds.

Selecting the range

The multimeter’s selected range is always displayed at the right end of the bar

graph. Pressing enables manual ranging while pressing for

Introduction 1

> 1 second enables autoranging. It also cycles through the available multimeter ranges when manual ranging is enabled.

Autoranging is convenient because the multimeter automatically selects an appropriate range for sensing and displaying each measurement. However, manual ranging results in better performance since the multimeter does not have to determine which range to use for each measurement.

The range is fixed for diode tests, temperature, current (A), and Z

LOW

measurements.

In autorange, the multimeter selects the lowest range to display the highest available precision (resolution) for the input signal. If manual range is already

enabled, press for > 1 second to enter the autoranging mode.

If autoranging is enabled, press to enter the manual range mode.

Keysight U1241C/U1242C User’s Guide 27

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1Introduction

Range

Auto

CAUTION

Each additional press of sets the multimeter to the next higher range,

unless it is already in the highest range, at which point the range switches to the lowest range.

Alerts and warnings during measurement

Hazardous voltage indication

The multimeter will display the hazardous voltage ( ) symbol as an early precaution when the measured voltage is:

Measurement DC AC

V (mV)

≥ +30 V or +OL (voltage overload) ≤ –30 V or –OL ≥ 30 V or OL

This symbol will also be displayed when the input signal exceeds the limitation of measuring circuit as frequency dependence.

Hazardous current indication

The multimeter will display the symbol as an early precaution when the measured current has reached the maximum fuse rating as follows:

Measurement DC AC

μA/mA

≥ +11 A or +OL (current overload) ≤ –11 A or –OL ≥ 11 A or OL

≥ 440 mA or +OL ≤ –440 mA or –OL ≥ 440 mA or OL

If your measuring current is > 10 A ~ 19.999 A, you will need to lower the current within a 30 seconds time limitation to avoid blowing the multimeter’s fuse.

28 Keysight U1241C/U1242C User’s Guide

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Introduction 1

CAUTION

Vsense

U1242C

True RMS Multimeter

COM

LOW

Range

Shift

Hold

Esc

Vsense

MaxMin

Auto

Log

View

600V

CAT III 1000V

CAT IV

MAX

FUSED

10A MAX FUSED

440mA

Input warning

To avoid circuit damage and possibly blowing the mul timeter’s current fuse, do not place the probes across (in parallel with) a powered circuit when a lead is plugged into a current terminal. This causes a short circuit because the resistance through the multimeter's current terminals is very low.

The multimeter emits a continuous beep and the red LED indicator lights up when the test lead is inserted into the or input terminal but the rotary switch is

not set to the correct current position. The secondary display will show or

until the test lead is removed. The beeping will stop automatically after

5 seconds even if the test lead is not removed.

Figure 1-2 Example of wrong terminal input

Keysight U1241C/U1242C User’s Guide 29

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1Introduction

To PC (host)

IR-USB cable

Pull until maximum reach

This warning is intended to stop you from attempting to measure voltage, continuity, resistance, capacitance, diode, or temperature values when the leads are plugged into a current terminal.

When the rotary switch is set to the current measurement position but no lead is inserted into its respective input terminal, the multimeter emits a continuous beep

and the red LED indicator lights up. The secondary display will show , and the warning alert will stop after 3 seconds approximately.

Figure 1-3 LEAd input warning display

Adjusting the tilt stand

To adjust the multimeter to a 60° standing position, pull the tilt stand outward to its maximum reach.

Figure 1-4 Tilt-stand ad justment and IR-USB cable connection

30 Keysight U1241C/U1242C User’s Guide

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Remote communication

You can communicate remotely with the multimeter from your PC via an IR-to-USB connection (see Using an IR-to-USB cable) or an IR-to-Bluetooth

connection (see Using a Bluetooth adapter).

When configuring the IR interface of the multimeter, use the following settings as the default:

– Baud rate: 9600 bits per second

– Parity bit: None

– Data bit: 8 data bits

– Number of stop bit: 1 bit

You can also use any of the following software to communicate with the multimeter:

– Keysight Handheld Meter Logger (for Windows PC)

– Keysight Mobile Meter (for Android or iOS devices)

– Keysight Mobile Logger (for Android or iOS devices)

Introduction 1

Using an IR-to-USB cable

The U1173B IR-to-USB cable (included in the shipment) can be used to connect your multimeter to your PC via the IR communication link (IR communication port, located at the rear panel). Ensure that the Keysight logo on the IR-to-USB cable that connects to the multimeter is facing up. Firmly push the IR head into the multimeter’s IR communication port until it snaps into place (see Figure 1-4).

Using a Bluetooth adapter

The U1117A Infrared (IR)-to-Bluetooth adapter (purchased separately) allows you to connect the multimeter wirelessly to any Windows PC, Android device, or iOS device.

The U1117A is compatible with the following application or software:

– Keysight Handheld Meter Logger (for Windows PC)

– Keysight Mobile Meter (for Android or iOS devices)

– Keysight Mobile Logger (for Android or iOS devices)

Keysight U1241C/U1242C User’s Guide 31

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1Introduction

Bluetooth adapter

Snap the optic side of the U1117A to the multimeter’s IR communication port.

Figure 1-5 Bluetooth adapter connection

Refer to the U1117A IR-to-Bluetooth Adapter Operating Instructions (downloadable from http://www.keysight.com/find/U1117A) for more information on how to set up the U1117A with a Windows PC, an Android device, or an iOS device.

32 Keysight U1241C/U1242C User’s Guide

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Introduction 1

Using the Handheld Meter Logger Software

You can use the IR communication link and the Keysight Handheld Meter Logger software to control your multimeter remotely, perform data logging operations, and transfer the contents of your multimeter’s memory to a PC. Refer to the Handheld Meter Logger Software Help File for more information on the IR communication link and the Handheld Meter Logger software.

Figure 1-6 Handheld Meter Logger software

You can download the Handheld Meter Logger software and its supporting documents from http://www.keysight.com/find/hhmeterlogger.

Keysight U1241C/U1242C User’s Guide 33

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1Introduction

Shift

Esc

View

MaxMin

Hold

Log

Vsense

Shift

Esc

View

Power-on options

Some options can be selected only while you turn the multimeter on. To select a power-on option, press and hold the specified key while turning the rotary switch to any other position (OFF to on). Power-on options remain selected until the multimeter is turned off.

Tab le 1-2 Power-on options

Key Description

Accesses the multimeter’s Setup menu. Press this key for > 1 second to exit the Setup menu.

Simulates the APO (auto power off) mode. Press any key to turn the multimeter back on and resume normal operation.

Tests the LCD. All LCD annunciators are lit. Use this mode to verify that there are no defective LCD annunciators. Press any key to exit this mode.

Turns on the flashlight. Press or to change the brightness level (with

the backlight turned on at the same time). Press for > 1 second to exit this mode.

34 Keysight U1241C/U1242C User’s Guide

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Your Multimeter in Brief

Overview

Front panel

Introduction 1

Figure 1-7 Front panel

Table 1-3 Front panel parts

Legend Description Learn more on:

1 Vsense red LED indicator page 96

2 Display screen page 42

3 Keypad page 39

4 Rotary switch page 37

5 Input terminals page 47

Keysight U1241C/U1242C User’s Guide 35

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1Introduction

Rear panel

Figure 1-8 Rear panel

Tab le 1-4 Rear panel parts

Legend Description Learn more on:

1 Flashlight page 34 and page 41

2 IR communication port page 31

3 Test lead/probe holders —

4 Battery and fuse access cover page 24

5 Tilt stand page 30

36 Keysight U1241C/U1242C User’s Guide

Page 37

Rotary switch

NOTE

Shift

Esc

View

Shift

Esc

View

WARNING

LOW

Table 1-5 describes the measurement functions for each rotary switch position. Turning the rotary switch changes the measurement function and resets all other measurement options.

Some rotary switch positions have a shifted function printed in orange. Press

more information on .

Remove the test leads from the measuring source or target before changing the rotary switch position.

Introduction 1

to switch between the shifted and regular functions. See page 41 for

Figure 1-9 Rotary switch

Table 1-5 Rotary switch functions

Legend Description Learn more on:

[a]

Low impedance AC or DC voltage measurement for eliminating stray voltages

page 61

Off page 26

Keysight U1241C/U1242C User’s Guide 37

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1Introduction

Tab le 1-5 Rotary switch functions (continued)

Legend Description Learn more on:

[a] U1242C only.

AC voltage measurement or harmonic ratio function

[a]

page 53 and

page 55

DC voltage measurement page 57

Resistance measurement or continuity test

Diode test or capacitance measurement

page 63 and

page 66

page 69 and

page 73

AC or DC current measurement (up to milliamperes) page 85

AC or DC current measurement page 85

Temperature (T1, T2

[a]

, or T1–T2 mV measurement (when enabled from the Setup menu; refer to “Changing the thermocouple type or setting the

[a]

) measurement or AC/DC

page 59 and

page 79

mV measurement” on page 126)

38 Keysight U1241C/U1242C User’s Guide

Page 39

Keypad

Range

ShiftHold

Esc

Vsense

MaxMin

Auto

Log

View

MaxMin

MaxMinHzMaxMin

Vsense

Table 1-6 describes the operation of each key. Pressing a key enables a function, displays a related symbol, and emits a beep. Turning the rotary switch to another position resets the current operation of the key.

Figure 1-10 Keys

Table 1-6 Keypad functions

Introduction 1

Legend

Function when pressed for:

Less than 1 second More than 1 second

Enables the frequency test mode for vol tage or current measurements.

– Press again to scroll through the low

pass frequency filter ( ), voltage/current measurement, and frequency (Hz) measurement.

Sets the Null/Relative mode.

– The displayed value is saved as a reference to

be subtracted from subsequent measurements.

– While in Null mode, press again to view

the stored reference value that has been saved. The display will return to normal after 3 seconds.

– Pressing while the relative value is

being displayed will cancel the Null mode.

Starts the dynamic (Max/Min/Avg) recording.

– Press again to cycle through

maximum (Max), minimum (Min), average (Avg), and present (MaxMinAvg) readings.

Stops and exits the dynamic (Max/Min/Avg) record ing.

Toggles on/off non-contact voltage detection (Vsense).

Learn more

on:

page 75

and

page 100

page 96

and

page 98

Keysight U1241C/U1242C User’s Guide 39

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1Introduction

Range

Auto

Range

Auto

Hold

Log

Hold

Log

Hold

Log

Hold

Log

Hold

Log

Hold

Log

Hold

Log

Hold

Log

Tab le 1-6 Keypad functions (continued)

Legend

Function when pressed for:

Less than 1 second More than 1 second

Sets a manual range and d isables autoranging.

– Press again to cycle through each

available measurement range.

Switches between environment temperature compensation (ETC) and non-ETC (0 °C) for temperature measurements.

Changes the Vsense detector sensitivity.

Freezes the present reading in the d isplay ( mode).

– In the mode, press to

manually trigger the holding of the next measured value.

Automatically freezes the present reading once the reading is stable ( mode;

when enabled from the multimeter’s Setup mode).

– In the mode, the reading is

updated automatically once the reading is stable and the count setting is exceeded.

– Press again to exit this mode.

Stores a record of the measured signal and exports it via the mul timeter’s optical communication port.

Enables autoranging.

Switches between the temperature unit (°C or °F) for temperature measurements when enabled from the multimeter’s Setup mode.

Press for > 1 second to unlock this

setting.

Starts and stops data logging.

– If data logging is set as (manual data

logging), pressing for > 1 second will log the present reading into the memory. The

display will return to normal after a short while (≈ 1 second). To manually log another

reading, press again for > 1 second.

– If data logging is set as (interval data

logging), pressing for > 1 second will enter the interval data logging mode, where

data is logged at the interval defined in the multimeter’s Setup mode.

– If data logging is set as (event data

logging), pressing for > 1 second will enter the event data logging mode, where

data is logged each time a triggering condition is satisfied.

Learn more

on:

page 27, page 79,

and

page 128

page 100, page 102, page 104,

and

page 128

Restarts the dynamic (Max/Min/Avg) recording.

Unlocks the temperature unit display setting in the Setup mode.

40 Keysight U1241C/U1242C User’s Guide

Page 41

Table 1-6 Keypad functions (continued)

Shift

Esc

View

Shift

Esc

View

MaxMin

Range

Auto

Vsense

Hold

Log

Hold

Log

Vsense

Shift

Esc

View

Introduction 1

Legend

Function when pressed for:

Less than 1 second More than 1 second

Turns the backlight on or off. Turns the flashlight on or off.

Enters and exits the Log Review menu (with the Hold mode disabled)

– Press again to cycle through the

previously recorded export ( ), manual (H), interval (A), or event (E) logging data.

– Press or to view the first or

last logged data respectively. Press or

Switches between the regular and shifted (icon printed in orange above the rotary switch position — if available) measurement functions.

Enables the Scan mode for temperature measurements (U1242C only).

to scroll through the logged data.

– Press for > 1 second to clear all the

logged data for the selected logging mode.

Press to clear the last logged data only.

– Press for > 1 second to sanitize the log

memory when data of all logging modes have been cleared.

Learn more

on:

page 27

and

page 123

page 34,

page 37,

page 84,

page 110,

and

page 114

Exits the or mode.

Press while turning the rotary switch (from OFF to on) to access the Setup menu.

Keysight U1241C/U1242C User’s Guide 41

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1Introduction

Display screen

Tab le 1-7 describes the general display annunciators of your multimeter. See also “Measurement units” on page 45 for a list of available measurement signs and notations and “Analog bar graph” on page 46 for a tutorial on the analog bar graph located at the bottom of your display screen.

General display annunciators

Figure 1-11 Display screen

Tab le 1-7 General annunciators

Legend Description Learn more on:

Remote control enabled —

Averaging sense measurements for sine waves

[a]

Scan

Low pass filter for frequency measurements page 78

Data logging in progress page 104

Data logging type page 104

Data log export in progress page 104

View mode for reviewing previously logged data page 110

, T1, T2

[a]

, and T1-T2

[a]

for temperature measurements

[a]

page 53, page 55, page 59, page 75,

and page 85

page 79

42 Keysight U1241C/U1242C User’s Guide

Page 43

Table 1-7 General annunciators (continued)

Legend Description Learn more on:

Secondary measurement display —

Introduction 1

AC or DC indication for the secondary display

page 55, page 61,

and page 75

Measuring units for the secondary display page 44

Smooth mode enabled page 120

Harmonic ratio indication

[a]

page 37 and page 55

DC filter enabled for DC voltage measurements page 138

Hazardous voltage sign for measuring voltage ≥30 V or overload Hazardous current sign for measuring current exceeding the fuse rating

page 28 and page 96

Trigger hold enabled page 102

Auto hold enabled

page 102 and

page 119

Maximum reading shown on primary display

Minimum reading shown on primary display

Averaged reading shown on primary display

page 100

Dynamic recording mode for Max, Min, Avg, and present (MaxMinAvg) display

Relative (Null) enabled page 98

Audible continuity test selected

J-type thermocouple selected

K-type thermocouple selected

[a]

page 66, page 131,

and page 132

page 79 and

page 126

Temperature measurement without ambient compensation selected page 83

Keysight U1241C/U1242C User’s Guide 43

Page 44

1Introduction

Tab le 1-7 General annunciators (continued)

Legend Description Learn more on:

Measuring units for the primary display page 44

0-20 mA % scale mode selected

4-20 mA % scale mode selected

Primary measurement display

DC (direct current)

page 91 and

page 139

—

page 57, page 59,

and page 85

page 53, page 59,

AC (alternating current)

page 61, page 85,

and page 96

– Capacitor is charging (during capacitance measurement) – Open continuity

page 66 and page 73

– Capacitor is discharging (during capacitance measurement) – Short continuity

Analog bar graph and measurement range page 27 and page 46

Autoranging enabled page 27

Diode test selected page 69

Tone enabled

—

Battery capacity indication page 24

Auto power off (APO) enabled

Overload (the reading exceeds the display range)

[a] U1242C only.

page 26, page 34,

and page 121

—

44 Keysight U1241C/U1242C User’s Guide

Page 45

Introduction 1

Measurement units

Table 1-8 describes the available signs and notations for each measurement function in your multimeter. The units listed below are applicable to the primary display and secondary display measurements of your multimeter.

Table 1-8 Measurement units display

Sign/Notation Description

M Mega 1E+06 (1000000)

k kilo 1E+03 (1000)

n nano 1E–09 (0.000000001)

μ micro 1E–06 (0.000001)

m milli 1E–03 (0.001)

mV, V Voltage units for voltage measurement

A, mA, μA Ampere units for current measurement

nF, μF, mF Farad units for capacitance measurement

Ω, kΩ, MΩ Ohm units for resistance measurement

MHz, kHz, Hz Hertz units for frequency measurement

°C Degree Celsius, unit for temperature measurement

°F Degree Fahrenheit, unit for temperature measurement

Percent, unit for the scale proportional to DC 0~20 mA

Percent, unit for the scale proportional to DC 4~20 mA

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1Introduction

Analog bar graph

The analog bar emulates the needle on an analog multimeter, without displaying the overshoot. When measuring peak or null adjustments and viewing fast-changing inputs, the bar graph provides a useful indication because it has a

faster updating rate

For frequency, 4-20 mA % scale, 0-20 mA % scale, and temperature measurements, the bar graph does not represent the primary display value.

For example, when frequency is displayed on the primary display during voltage or current measurement, the bar graph represents the voltage or current value (not the frequency value). Another example is when the 4-20 mA % scale or 0-20 mA % scale is displayed on the primary display, the bar graph represents the current value and not the percentage value.

The “+” or “–” sign indicates whether the measured or calculated value is positive or negative. Each segment represents 250 counts based on 10000 counts depending on the range indicated on the peak bar graph.

Tab le 1-9 Analog bar graph display

Range Counts/Segments Used for the function

[1]

to cater to fast-response applications.

500

250

V, mV, μA/mA/A, Ω,

An unstable bar graph and unmatched primary display when measuring DC voltage usually means the presence of AC voltages in the circuit.

[1] The analog bar graph measurement rate is > 30 times/second for DC voltage, current, and resistance

measurements.

46 Keysight U1241C/U1242C User’s Guide

Page 47

Input terminals

WARNING

CAUTION

Table 1-10 describes the terminal connections for the different measurement functions of your multimeter. Observe the rotary switch position of your multimeter before connecting the test leads to the connector terminals.

Ensure that the terminal connections are correct for that particular measurement function before starting any measurement.

To avoid damaging this multimeter, do not exceed the rated input limit.

Introduction 1

Keysight U1241C/U1242C User’s Guide 47

Figure 1-12 Connector terminals

Page 48

1Introduction

LOW

COM

Table 1-10 Terminal connections for different measurement functions

Rotary switch

position

[a]

Input terminals Overload protection

1000 Vrms

1000 Vrms for short circuit <0.3 A

440 mA/1000 V, fast-acting fuse

11 A/1000 V, fast-acting fuse

[a] Also includes the AC/DC mV function when enabled from the Setup menu. Refer to “Measuring AC or DC mV”

on page 59.

48 Keysight U1241C/U1242C User’s Guide

Page 49

Cleaning Your Multimeter

WARNING

To avoid electrical shock or damage to the mul timeter, ensure that the insides of the casing stay dry at all times.

Dirt or moisture in the terminals can distort readings. Follow the steps below to clean your multimeter.

1 Turn the multimeter off and remove the test leads.

2 Turn the multimeter over and shake out any dirt that may have accumulated in

the terminals.

3 Wipe the case with a damp cloth and mild detergent — do not use abrasives or

solvents. Wipe the contacts in each terminal with a clean swab dipped in alcohol.

Introduction 1

Keysight U1241C/U1242C User’s Guide 49

Page 50

1Introduction

THIS PAGE HAS BEEN INTENTIONALLY LEFT BLANK.

50 Keysight U1241C/U1242C User’s Guide

Page 51

Keysight U1241C/U1242C Handheld Digital Multimeter User’s Guide

2 Making Measurements

Crest Factor 52 Measuring AC Voltage 53 Measuring Harmonic Ratio (U1242C only) 55 Measuring DC Voltage 57 Measuring AC or DC mV 59 Using Z

Measuring Resistance 63 Testing for Continuity 66 Testing Diodes 69 Measuring Capacitance 73 Measuring Frequency 75 Measuring Temperature 79 Measuring AC or DC Current 85

for Voltage Measurements (U1242C only) 61

LOW

The following sections describe how to take measurements with your multimeter.

Page 52

2 Making Measurements

Crest factor

Peak value

True rms value

--------------------------------=

WARNING

Crest Factor

The crest factor may be determined by using this formula:

The crest factor may be up to 3.0 at full scale except for the 1000 V and 600 mV ranges, where these ranges are 1.5 at full scale. For non-sinusoidal waveforms, add (0.5% reading + 0.3% full scale) typically.

Voltage range Crest factor

100 mV 3 300 mV

600 mV 1.5 900 mV

1000 mV 3 3000 mV

10 V 3 30 V

100 V 3 300 V

1000 V 1.5 1500 V

Maximum input (V

peak

)

Exceeding the crest factor limit may resul t in an incorrect or a lower reading. Do not exceed the crest factor limit to avoid instrument damage and the risk of electric shock.

52 Keysight U1241C/U1242C User’s Guide

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Measuring AC Voltage

Shift

Esc

View

NOTE

Set up your multimeter to measure AC voltage as shown in Figure 2-2. Probe the test points and read the display.

Table 2-1 Rotary switch position allowing AC voltage measurements

Making Measurements 2

Legend Default function

Function when is pressed

Cycles between

[a]

with AC V (averaging sense)

[a]

with AC V (true rms), or

AC V (true rms)

–AC V (averaging sense)

– Harmonic ratio

– Harmonic ratio – AC V (true rms)

[a] U1242C only. The averaging sense AC measurement applies for sine wave inputs only. It provides more accurate

readings for linear loads measurement such as standard induction motors, resistance heating, and incandescent lights.

AC voltage measurements measured with this multimeter are returned as average response readings for sine waves (for U1242C only) or true rms read ings.

Figure 2-1 AC voltage display

Keysight U1241C/U1242C User’s Guide 53

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2 Making Measurements

NOTE

MaxMin

Vsense

U1242C

True RMS Multimeter

COM

LOW

Range

Shift

Hold

Esc

Vsense

MaxMin

Auto

Log

View

600V

CAT III 1000V

CAT IV

MAX

FUSED

10A MAX FUSED

440mA

Press to enable the frequency test mode for voltage measurements.

Refer to “Measuring Frequency” on page 75.

Figure 2-2 Measuring AC voltage

54 Keysight U1241C/U1242C User’s Guide

Page 55

Measuring Harmonic Ratio (U1242C only)

Shift

Esc

View

NOTE

The harmonic ratio function indicates the deviation of non-sinusoidal to sinusoidal waveform from the range of 0% to 100%, which indicates the presence of harmonics. A pure sinusoidal waveform without harmonics gives a value of 0%. A higher harmonic ratio means more harmonics are present on the signal.

Table 2-2 Rotary switch position allowing harmonic ratio measurements

Making Measurements 2

Legend Default function

AC V (true rms)

[a] U1242C only.

Function when is pressed

Cycles between

–AC V (averaging sense)

– Harmonic ratio

– Harmonic ratio – AC V (true rms)

[a]

with AC V (averaging sense)

[a]

with AC V (true rms), or

To set up your multimeter to measure harmonic ratio, first set up your multimeter to measure AC voltage as shown in Figure 2-2. Probe the test points and read the display.

The harmonic ratio measurement is shown in the primary display and the AC voltage measurement is shown in the secondary display.

Keysight U1241C/U1242C User’s Guide 55

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2 Making Measurements

Press

Shift

Esc

View

Figure 2-3 Harmonic ratio measurement

56 Keysight U1241C/U1242C User’s Guide

Page 57

Measuring DC Voltage

NOTE

CAUTION

Set up your multimeter to measure DC voltage as shown in Figure 2-5. Probe the test points and read the display.

Table 2-3 Rotary switch position allowing DC voltage measurements

Legend Default function

This multimeter displays DC voltage values as well as their polarity. Negative DC voltages will return a negative sign on the left of the display.

If you are measuring a signal which includes AC components and the peak value is exceeding the measurement range, you will need to lock a range that is greater than the peak of voltage. Use the maximum range of 1000 V to check the signal condition, and manually select a suitable range for the signal.

Making Measurements 2

DC V

As the DC voltage measurement has the Normal (Series) Mode Rejection Rate (NMRR) capability for 50/60 Hz noise, a hazardous voltage indication of

will be shown even if the display is showing 0 V or < 30 V. The

measurement range will automatically be set to a higher range, and the analog bar graph will be varying fast or greater than the displayed value.

Figure 2-4 DC voltage display

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2 Making Measurements

NOTE

MaxMin

Vsense

U1242C

True RMS Multimeter

COM

LOW

Range

Shift

Hold

Esc

Vsense

MaxMin

Auto

Log

View

600V

CAT III 1000V

CAT IV

MAX

FUSED

10A MAX FUSED

440mA

Press to enable the frequency test mode for voltage measurements.

Refer to “Measuring Frequency” on page 75.

Figure 2-5 Measuring DC voltage

58 Keysight U1241C/U1242C User’s Guide

Page 59

Measuring AC or DC mV

NOTE

Shift

Esc

View

NOTE

You can set the multimeter to measure AC or DC mV at the following rotary switch position (you must first enable the mV measurement function from the Setup menu. Refer to “Changing the thermocouple type or setting the mV measurement” on page 126.).

When this Setup item is enabled, the original temperature functions offered in this rotary switch position are disabled and replaced by AC or DC mV measurements.

Table 2-4 Rotary switch position allowing AC or DC mV measurements

Making Measurements 2

Legend Default function

DC mV

[a] U1242C only.

Function when is pressed

Cycles between – AC mV (true rms)

– AC mV (averaging sense) –DC mV

[a]

, or

It is recommended to use the mV function when measuring low voltages.

Set up your multimeter to measure voltage as shown in Figure 2-2 or Figure 2-5. Probe the test points and read the display.

Keysight U1241C/U1242C User’s Guide 59

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2 Making Measurements

NOTE

MaxMin

Figure 2-6 DC mV display

– For AC or DC mV measurements, the measurement range is fixed at 100 mV

or 1000 mV, and the input impedance can be set as 10 MΩ (by default) or >1000 MΩ. Refer to “Setting the input impedance” on page 137.

– Press to enable the frequency test mode for voltage measurements.

Refer to “Measuring Frequency” on page 75.

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Making Measurements 2

CAUTION

LOW

NOTE

Using Z

for Voltage Measurements (U1242C only)

LOW

Do not use the Z damaged by this function’s low impedance (

The low input impedance (Z

function to measure voltages in circuits that could be

LOW

≈2 kΩ).

) function in your multimeter presents a low

LOW

impedance across the leads to obtain a more accurate measurement.

Table 2-5 Rotary switch position allowing Z

Legend Default function

(AC/DC) V

LOW

To set up your multimeter to make a Z

voltage measurement, first set up your

LOW

multimeter to measure voltage as shown in Figure 2-2 or Figure 2-5. Probe the test points and read the display.

The AC voltage measurement is shown in the primary display and the DC voltage measurement is shown in the secondary display.

measurements

LOW

Use the low input impedance (Z

) function to remove stray or induced

LOW

voltages from your measurements.

Stray (ghost) voltages are voltages present on a circuit that should not be energized. Stray voltages can be caused by capacitive coupling between energized wiring and adjacent unused wiring.

can remove stray voltages from your measurements by dissipating the

LOW

coupling voltage. Use Z

to reduce the possibility of false readings in areas

LOW

where the presence of stray voltages are suspected.

You can also use Z resid ual-current circuit breaker (RCCB). Z

for tripping a residual-current device (RCD) or a

LOW

can discharge stray voltages from

LOW

probes touching on terminals after the RCD or RCCB is tripped. This will prevent false readings in voltage measurements with high-input impedance after a power off or trip.

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2 Making Measurements

NOTE

Figure 2-7 Z

During Z

measurements, autoranging is disabled and the multimeter’s range

LOW

display

is set to 1000 V in the manual ranging mode.

Use Z

to test a battery’s health

LOW

Aside from reading a battery’s voltage level using the DC voltage measurement function, you can also use the Z

If you detect that the measured battery’s voltage shown in the Z

function to test a battery’s health.

LOW

function is

LOW

declining gradually, this means that the capacity of the battery-under-test is not enough to support regular functions. Use this simple and quick test to determine if a battery has enough voltage capacity to support regular activities.

Prolonged use of the Z

function will consume the capacity of the

LOW

battery-under-test.

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Measuring Resistance

CAUTION

Shift

Esc

View

To avoid possible damage to your multimeter or to the equipment-under-test, disconnect the circuit power and discharge all high-voltage capacitors before measuring resistance.

Set up your multimeter to measure resistance as shown in Figure 2-9. Probe the test points and read the display.

Table 2-6 Rotary switch position allowing resistance measurements

Making Measurements 2

Legend Default function

Resistance measurement (Ω)

Figure 2-8 Resistance display

Function when is pressed

Continuity test ( )

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2 Making Measurements

Vsense

U1242C

True RMS Multimeter

COM

LOW

Range

Shift

Hold

Esc

Vsense

MaxMin

Auto

Log

View

600V

CAT III 1000V

CAT IV

MAX

FUSED

10A MAX FUSED

440mA

Figure 2-9 Measuring resistance

64 Keysight U1241C/U1242C User’s Guide

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Making Measurements 2

NOTE

Vsense

Keep the following in mind when measuring resistance.

– The test leads can add 0.1 Ω to 0.2 Ω of error to resistance measurements. To

test the leads, touch the probe tips together and read the resistance of the leads. To remove lead resistance from the measurement, hold the test lead

tips together and press . Now the resistance at the probe tips will be

subtracted from all future display readings.

– Be aware that the resistance function can produce enough voltage to

forward-bias silicon diode or transistor junctions.

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2 Making Measurements

CAUTION

Shift

Esc

View

NOTE

Range

Auto

Testing for Continuity

To avoid possible damage to the multimeter or to the equipment-under-test, disconnect circuit power and discharge all high-voltage capacitors before measuring continuity. Use the DC voltage function to confirm that the capacitor is fully discharged.

Set up your multimeter to test for continuity as shown in Figure 2-10. Probe the test points and read the display.

Tab le 2-7 Rotary switch position allowing continuity tests

Legend Default function

Resistance measurement (Ω)

Function when is pressed

Continuity test ( )

The continuity test features a beeper that sounds and a red LED indicator that lights up as long as a circuit is incomplete or broken. The audible and visual alerts allow you to perform quick continuity tests without having to watch the display.

In continuity, a short means a measured value is less than the threshold resistance

values listed in Table 2-8. Press to select different threshold resistance

values.

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Making Measurements 2

NOTE

Table 2-8 Threshold resistance values

Range Resolution Accuracy Continuity threshold Overload protection

100 Ω 0.01 Ω 0.2% +5 28 ± 10 Ω

1000 Ω 0.1 Ω 0.2% +2 28 ± 10 Ω

10 kΩ 0.001 kΩ 0.2% +2 0.151 ± 0.05 kΩ

100 kΩ 0.01 kΩ 0.2% +2 1.38 ± 0.5 kΩ

1000 kΩ 0.1 kΩ 0.2% +2 13.8 ± 4.3 kΩ

10 MΩ 0.001 MΩ 0.8% +2 0.12 ± 0.04 MΩ

100 MΩ 0.01 MΩ

1.5% +3 (< 50 MΩ)

3.0% +3 (> 50 MΩ)

0.12 ± 0.04 MΩ

1000 Vrms < 0.3 A short circuit current

You can set the beeper to sound and the red LED indicator to light up as a continuity indication whether the circuit-under-test is less than (short) or more than or equal to (open) the threshold resistance. Refer to “Changing the continuity type” on page 131.

– Normal open: The circuit is normally open, the beeper will sound and the LED

indicator will light up when a short is detected.

– Normal closed: The circuit is normally closed, the beeper will sound and the

LED indicator will light up when an open is detected.

The audible continuity will be locked in the minimum range of 1000 Ω for resistance measurement.

– The continuity function detects intermittent shorts and opens lasting as

briefly as 1 ms. A brief short or open causes the multimeter to emit a short beep and its red LED indicator to light up.

– You can enable or disable the audible and visual alerts via the multimeter’s

Setup. Refer to “Changing the continuity alert type” on page 132.

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2 Making Measurements

Vsense

U1242C

True RMS Multimeter

COM

LOW

Range

Shift

Hold

Esc

(closed)

OFF

(open )

Shift

Esc

View

Vsense

MaxMin

Auto

Log

View

600V

CAT III 1000V

CAT IV

MAX

FUSED

10A MAX FUSED

440mA

Figure 2-10 Testing for continuity

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Testing Diodes

CAUTION

Shift

Esc

View

NOTE

To avoid possible damage to your multimeter or to the equipment-under-test, disconnect the circuit power and discharge all high-voltage capacitors before testing diodes.

Set up your multimeter to test diodes as shown in Figure 2-13. Probe the test points and read the display.

Table 2-9 Rotary switch position allowing diode tests

Making Measurements 2

Legend Default function

Diode test ( )

Function when is pressed

Capacitance measurement ( )

– Use the diode test to check diodes, transistors, silicon controlled rectifiers

(SCRs), and other semiconductor devices. A good d iode allows current to flow in one direction only.

– This test sends a current through a semiconductor junction and then

measures the junction’s voltage drop. A typical junction drop is 0.3 V to 0.8 V.

– Connect the red test lead to the positive terminal (anode) of the diode and

the black test lead to the negative terminal (cathode).

Figure 2-11 Diode display

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2 Making Measurements

NOTE

– Your multimeter can display diode forward bias of up to approximately 2.1 V.

The forward bias of a typical diode is within the range of 0.3 V to 0.8 V; however, the reading can vary depending on the resistance of other pathways between the probe tips.

– If the beeper is enabled during a diode test, the multimeter will emit a beep

for a normal junction and a continuous beep for a shorted junction below

0.050 V. See “Changing the beep frequency” on page 129 to disable the beeper.

Reverse the probes (as shown in Figure 2-14) and measure the voltage across the diode again. Assess the diode according to the following guidelines:

– A diode is considered good if the multimeter displays OL in reverse bias mode.

– A diode is considered shorted if the multimeter displays approximately 0 V in

both forward and reverse bias modes, and the multimeter beeps repeatedly.

– A diode is considered open if the multimeter displays OL in both forward and

reverse bias modes.

Figure 2-12 Open diode display

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Making Measurements 2

Vsense

U1242C

True RMS Multimeter

COM

LOW

Range

Shift

Hold

Esc

Vsense

MaxMin

Auto

Log

View

600V

CAT III 1000V

CAT IV

MAX

FUSED

10A MAX FUSED

440mA

Figure 2-13 Testing a forward bias diode

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2 Making Measurements

Vsense

U1242C

True RMS Multimeter

COM

LOW

Range

Shift

Hold

Esc

Vsense

MaxMin

Auto

Log

View

600V

CAT III 1000V

CAT IV

MAX

FUSED

10A MAX FUSED

440mA

Figure 2-14 Testing a reverse bias diode

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Measuring Capacitance

CAUTION

Shift

Esc

View

NOTE

To avoid possible damage to the multimeter or to the equipment under test, disconnect circuit power and discharge all high-voltage capacitors before measuring capacitance. Use the DC voltage function to confirm that the capacitor is fully discharged.

Set up your multimeter to measure capacitance as shown in Figure 2-16. Probe the test points and read the display.

Table 2-10 Rotary switch position allowing capacitance measurements

Making Measurements 2

Legend Default function

Diode test ( )

Function when is pressed

Capacitance measurement ( )

– The multimeter measures capacitance by charging the capacitor with a

known current for a known period of time, measuring the resulting voltage, and then calculating the capacitance.

– is shown on the bottom left of the display when the capacitor is charging,

and is shown when the capacitor is discharging.

Figure 2-15 Capacitance display

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2 Making Measurements

NOTE

Vsense

U1242C

True RMS Multimeter

COM

LOW

Range

Shift

Hold

Esc

–

Shift

Esc

View

Vsense

MaxMin

Auto

Log

View

600V

CAT III 1000V

CAT IV

MAX

FUSED

10A MAX FUSED

440mA

– To improve measurement accuracy of small value capacitors, press

with the test leads open to subtract the residual capacitance of the multimeter and leads.

– For measuring capacitance values > 1000 μF, discharge the capacitor first,

and then select a suitable range for measurement. This will speed up the measurement time and also ensure that the correct capacitance value is obtained.

Figure 2-16 Measuring capacitance

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Page 75

Measuring Frequency

WARNING

Shift

Esc

View

Never measure the frequency where the voltage or current level exceeds the specified range. Manually set the voltage or current range if you want to measure frequencies < 20 Hz.

Your multimeter allows simultaneous monitoring of real-time voltage or current with frequency measurements. Table 2-11 highlights the functions allowing frequency measurements in your multimeter.

Table 2-11 Rotary switch positions allowing frequency measurements

Making Measurements 2

Legend Defaul t function

AC V (true rms)

DC V —

DC A

DC mA (or μA)

[a] U1242C only.

Function when is pressed

Cycles between

– AC V (averaging sense)

– Harmonic ratio

[a]

with AC V (averaging sense)

[a]

with AC V (true rms), or

– AC V (true rms)

Cycles between – AC A (true rms)

– AC A (averaging sense)

[a]

, or

–DC A

Cycles between – % scale of 4-20 mA (or 0-20 mA) with DC mA (or μA) –AC mA (or μA) (true rms)

–AC mA (or μA) (averaging sense)

[a]

, or

–DC mA (or μA)

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2 Making Measurements

NOTE

Rise Time Fall Time

+ Width – Width

Period

90%

50%

10%

Rise time

Fall time

+ Width

– Width

Period

90%

50%

10%

Range

Auto

NOTE

MaxMin

– Measuring the frequency of a signal helps detect the presence of harmonic

currents in neutral conductors and determines whether these neutral currents are the result of unbalanced phases or non-linear loads.

– Frequency is the number of cycles a signal completes each second.

Frequency is defined as 1/Period. Period is defined as the time between the middle threshold crossings of two consecutive, like-polarity edges, as shown in Figure 2-17.

– The multimeter measures the frequency of a voltage or current signal by

counting the number of times the signal crosses a threshold level within a specified period of time.

76 Keysight U1241C/U1242C User’s Guide

Figure 2-17 Frequency measurement

Pressing controls the input range of the voltage or ampere and not the frequency range.

1 To measure frequency, rotate the switch to one of the primary functions

allowing frequency measurements highlighted in Table 2-11.

To obtain the best measuring results for frequency measurements, use the AC measuring path.

2 Probe the test points and press . Read the display.

Page 77

Making Measurements 2

MaxMin

Figure 2-18 Frequency display

The frequency of the input signal is shown in the primary display. The voltage or ampere value of the signal is shown in the secondary display. The bar graph does not indicate frequency but indicates the voltage or ampere value of the input signal.

Press to cycle through the low pass frequency filter function (see

page 78), voltage/current measurements, and frequency measurements.

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2 Making Measurements

MaxMin

Press

MaxMin

Using the low pass frequency filter function for frequency measurements

Your multimeter is equipped with a low pass frequency filter ( ) to help reduce unwanted noise when measuring frequency. When the filter is enabled, your multimeter continues measuring voltage/current via the selected averaging sense or true rms function, but now the signal diverts through a filter that blocks unwanted frequency of ~ 1 kHz. The filter with the averaging sense circuit can improve measurement performance on composite sine waves that are typically generated by inverters and variable frequency drives.

During frequency measurement, press to enable the low pass frequency

filter.

Figure 2-19 Low pass frequency filter function with averaging sense

78 Keysight U1241C/U1242C User’s Guide

Page 79

Measuring Temperature

WARNING

CAUTION

Shift

Esc

View

Do not connect the thermocouple to electrically live circuits. Doing so will potentially cause fire or electric shock.

Do not bend the thermocouple leads at sharp angles. Repeated bending over a period of time can break the leads.

The multimeter uses a type-K (default setting) or a type-J (U1242C only) temperature probe for measuring temperature. To measure temperature 1 (T1), set up your multimeter as shown in Figure 2-21.

Table 2-12 Rotary switch position allowing temperature measurements

Making Measurements 2

Legend Default function

Temperature 1 (T1)

[a] U1242C only.

Function when is pressed

Cycles between

– Temperature 2 (T2)

[a]

–T1–T2

[a]

–Scan –T1

, or

[a]

Probe the test points and read the display. The primary display normally shows temperature or the message OL (open thermocouple). The open thermocouple message may be due to a broken (open) probe or because no probe is installed into the input terminals of the multimeter.

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2 Making Measurements

Range

Auto

CAUTION

NOTE

COM

Figure 2-20 T1 temperature display

To measure temperature for T2 (U1242C only), connect the probe to the

input terminal.

[a] U1242C only.

Press

for > 1 second to change the temperature units between °C or °F

(you must first change the temperature unit to switch between °C and °F or °F and °C). Refer to “Changing the temperature unit” on page 128.

The option to change the temperature unit is locked for certain regions. Always set the temperature unit display per the official requirements and in compliance with the National laws of your region.

– Shorting the terminal to the terminal, or the terminal to the

terminal will display the temperature T1 or T2 at the multimeter’s

terminals respectively.

– To change the default thermocouple type from type-K to type-J

[a]

, see “Changing the thermocouple type or setting the mV measurement” on page 126.

80 Keysight U1241C/U1242C User’s Guide

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Making Measurements 2

NOTE

Temperature measurements via thermocouple sensors rely on cold junction compensation which reflects the ambient temperature. This ambient temperature is most important to ensure the accuracy of the thermocouple measurement. The multimeter must be placed in a stable operating environment for at least 1 hour to obtain a stable reference of the ambient temperature. The ambient temperature is shown on the secondary display for most measurements, which helps you to record the measurement reading and the ambient temperature as a controlled environment for checking a relative characteristic.

For applications with ambient temperature indication such as voltage reference, resistance temperature detector (RTD), thermistor, and poly-switch, the battery capacity or the measuring characteristic is referred on the operating temperature and additional temperature coefficients. Thus, the ambient temperature can only be used as a reference.

If you want to use a thermocouple other than the J or K type, you may use the DC 60 mV range with a 1 μV resolution and the ambient temperature in your application.

The bead-type thermocouple probe is suitable for measuring temperatures from –40 °C to 204 °C (399 °F) in PTFE-compatible environments. Above this temperature range, the probe may emit toxic gas. Do not immerse this thermocouple probe in any liquid. For best results, use a thermocouple probe designed for each specific application — an immersion probe for liquid or gel, and an air probe for air measurement.

Observe the following measurement techniques:

– Clean the surface to be measured and ensure that the probe is securely

touching the surface. Remember to disable the applied power.

– When measuring above ambient temperatures, move the thermocouple

along the surface until you get the highest temperature reading.

– When measuring below ambient temperatures, move the thermocouple

along the surface until you get the lowest temperature read ing.

– Place the multimeter in a stable operating environment for at least 1 hour to

obtain a stable reference of the ambient temperature for cold junction compensation of thermocouple temperature measurements.

– Allow the multimeter to cool down after high current measurements.

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2 Making Measurements

NOTE

Vsense

U1242C

True RMS Multimeter

COM

LOW

Range

Shift

Hold

Esc

Vsense

MaxMin

Auto

Log

View

600V

CAT III 1000V

CAT IV

MAX

FUSED

10A MAX FUSED

440mA

Type-K thermocouple probe

For quick measurement, use the compensation to view the temperature variation of the thermocouple sensor. The

measuring relative temperature immediately.

compensation assists you in

82 Keysight U1241C/U1242C User’s Guide

Figure 2-21 Measuring surface temperature (T1)

Page 83

Making Measurements 2

Range

Auto

Vsense

COM

Temperature measurement without ambient compensation

If you are working in a constantly varying environment, where ambient temperatures are not constant, do the following:

1 Press to select compensation. This allows a quick measurement of

the relative temperature.

2 Avoid contact between the thermocouple probe and the surface to be

measured.

3 After a constant reading is obtained, press

to set the reading as the

relative reference temperature.

4 Touch the surface to be measured with the thermocouple probe and read the

display.

Figure 2-22 Temperature measurement without ambient compensation

Dual temperature measurement for refrigeration applications

You can perform T1 and T2 temperature measurements to measure the efficiency of a condensor for an air conditioning unit as follows:

1 Plug the adapter with thermocouple probe into the and terminals

(T1) and the and terminals (T2) respectively.

2 Touch the condenser to be measured with the T1 thermocouple probe, and the

air surrounding the condenser with the T2 thermocouple probe. Read the display.

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2 Making Measurements

Shift

Esc

View

Scanning temperature measurements (U1242C only)

This scanning temperature measurement function allows you to measure and display temperature T1, T2, and T1–T2 sequentially.

1 Press

to step to the Scan mode.

2 In the Scan mode, the multimeter will scan through and display the values of

T1, T2, and T1–T2 periodically.

Figure 2-23 Scan mode for temperature measurements

84 Keysight U1241C/U1242C User’s Guide

Page 85

Measuring AC or DC Current

WARNING

CAUTION

Never attempt an in-circuit current measurement where the open-circuit potential to earth is greater than 1000 V. Doing so will cause damage to the multimeter and possible electric shock or personal injury.

To avoid possible damage to the mul timeter or to the equipment-under-test:

– Check the multimeter’s fuses before measuring current.

– Use the proper terminals, function, and range for your measurement.

– Never place the probes across (in parallel with) any circuit or component

when the leads are plugged into the current terminals.

Current can be measured at 440 mA continuously, and > 440 mA to 600 mA for 20 hours maximum. After measuring > 440 mA current, cool down the multimeter for twice the measuring time taken and use the Null function (see “Making Relative Measurements (Null)” on page 98) to zero the thermal effect before proceeding for low current measurement.

Making Measurements 2

Keysight U1241C/U1242C User’s Guide 85

Current can be measured at 10 A continuously, and 10 A ~ 20 A for 30 seconds maximum. After measuring > 10 A current, cool down the multimeter for twice the measuring time taken before proceeding for low current measurement.

Set up your multimeter to measure AC or DC current as shown in Figure 2-26 and Figure 2-27. Open the circuit path to be tested. Probe the test points and read the

display.

Page 86

2 Making Measurements

Shift

Esc

View

NOTE

Shift

Esc

View

Table 2-13 Rotary switch positions allowing current measurements

Legend Default function

Function when is pressed

Cycles between

DC A

– AC A (true rms)

–AC A (averaging sense)

[a]

, or

–DC A

Cycles between – % scale of 4-20 mA (or 0-20 mA) with DC mA (or μA)

DC mA (or μA)

–AC mA (or μA) (true rms)

–AC mA (or μA) (averaging sense)

[a]

, or

–DC mA (or μA)

[a] U1242C only.

– To measure current, you must open the circuit-under-test, and then place the

multimeter in series with the circuit.

– Turn off power to the circuit. Discharge all high-voltage capacitors. Insert the

black test lead into the terminal. Insert the red test lead in an input appropriate for the measurement range.

– If you are using the terminal, set the rotary switch to .

– If you are using the terminal, set the rotary switch to

for

current < 440 mA, or for current ≥ 440 mA.

– Press to cycle through different current measurements as stated in

Table 2- 13 .

– Reversing the leads will produce a negative read ing, but it will not damage

the multimeter.

86 Keysight U1241C/U1242C User’s Guide

Page 87

Making Measurements 2

CAUTION

NOTE

MaxMin

Figure 2-24 DC current display

– To avoid blowing the multimeter’s 440 mA fuse, use the terminal

only if you are sure the current is < 440 mA. See Figure 2-27 for test lead connections and function selection. Refer to the Alerts and warnings during measurement section for information on the alerts the multimeter uses for hazardous current or when leads are not used correctly during current measurement.

– Placing the probes across (in parallel with) a powered circuit when a lead

is plugged into a current terminal can damage the circuit you are testing and blow the multimeter's fuse. This happens because the resistance through the multimeter's current terminals are very low, resulting in a short circuit.

Press to enable the frequency test mode for current measurements.

Refer to “Measuring Frequency” on page 75.

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2 Making Measurements

Vsense

U1242C

True RMS Multimeter

COM

LOW

Range

Shift

Hold

Esc

LOAD

Vsense

MaxMin

Auto

Log

View

600V

CAT III 1000V

CAT IV

MAX

FUSED

10A MAX FUSED

440mA

Figure 2-25 Measuring DC current

88 Keysight U1241C/U1242C User’s Guide

Page 89

Making Measurements 2

Vsense

U1242C

True RMS Multimeter

COM

LOW

Range

Shift

Hold

Esc

Shift

Esc

View

LOAD

Vsense

MaxMin

Auto

Log

View

600V

CAT III 1000V

CAT IV

MAX

FUSED

10A MAX FUSED

440mA

Figure 2-26 Measuring AC current

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2 Making Measurements

Vsense

U1242C

True RMS Multimeter

COM

LOW

Range

Shift

Hold

Esc

Vsense

MaxMin

Auto

Log

View

600V

CAT III 1000V

CAT IV

MAX

FUSED

10A MAX FUSED

440mA

Vsense

U1242C

True RMS Multimeter

COM

LOW

Range

Shift

Hold

Esc

Vsense

MaxMin

Auto

Log

View

600V

CAT III 1000V

CAT IV

MAX

FUSED

10A MAX FUSED

440mA

Vsense

U1242C

True RMS Multimeter

COM

LOW

Range

Shift

Hold

Esc

Vsense

MaxMin

Auto

Log

View

600V

CAT III 1000V

CAT IV

MAX

FUSED

10A MAX FUSED

440mA

Current A measurement Current mA measurement

Current μA measurement

Figure 2-27 Current measurement setup

90 Keysight U1241C/U1242C User’s Guide

Page 91

% Scale of 4-20 mA or 0-20 mA

Shift

Esc

View

NOTE

To display the current measurement in % scale, position your multimeter’s rotary

Making Measurements 2

switch to

and set up your multimeter to measure DC current by following

the steps listed in “Measuring AC or DC Current” on page 85.

Table 2-14 Rotary switch positions allowing current measurements

Legend Defaul t function

DC mA (or μA)

[a] U1242C only.

Function when is pressed

Cycles between – % scale of 4-20 mA (or 0-20 mA) with DC mA (or μA) – AC mA (or μA) (true rms)

– AC mA (or μA) (averaging sense) –DC mA (or μA)

[a]

, or

The 4-20 mA current loop output from a transmitter is a type of electrical signal that is used in a series circuit to provide a robust measurement signal that is proportional to the applied pressure, temperature, or flow in process control. The signal is a current loop where 4 mA represents the 0% signal and 20 mA represents the 100% signal.

The % scale for 4-20 mA or 0-20 mA in this multimeter is calculated using its corresponding DC mA measurement. The multimeter will automatically optimize the best resolution for the selected measurement. Two ranges are available for the % scale as shown in Table 2-15.

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2 Making Measurements

Figure 2-28 4-20 mA % scale display

The analog bar graph displays the current measurement value. (In the example above, 8 mA is represented as 25% in the 4-20 mA % scale.)

Table 2-15 % scale measurement range

% scale of 4-20 mA or 0-20 mA DC mA measurement range

999.99%

9999.9%

~1000 mA

[a]

[a] Applies to both autoranging and manual range selection.

You can change the % scale range (4-20 mA or 0-20 mA) by accessing the multimeter’s setup. Refer to “Changing the % scale range” on page 139.

Use the % scale with a pressure transmitter, a valve positioner, or other output actuators to measure pressure, temperature, flow, pH, or other process variables.

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Making Measurements 2

Vsense

U1242C

True RMS Multimeter

COM

ZLOW

Range

Shift

Hold

Esc

Shift

Esc

View

Vsense

MaxMin

Auto

Log

View

600V

CAT III 1000V

CAT IV

MAX

FUSED

10A MAX FUSED

440mA

Figure 2-29 Measuring DC current using the 4-20 mA % scale

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2 Making Measurements

THIS PAGE HAS BEEN INTENTIONALLY LEFT BLANK.

94 Keysight U1241C/U1242C User’s Guide

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Keysight U1241C/U1242C Handheld Digital Multimeter User’s Guide

3 Multimeter Features

Detecting AC Voltage Presence (Vsense) (U1242C only) 96 Making Relative Measurements (Null) 98 Capturing Maximum and Minimum Values (MaxMin) 100 Freezing the Display (TrigHold and AutoHold) 102 Recording Measurement Data (Data Logging) 104 Reviewing Previously Recorded Data (View) 110

The following sections describe the additional features available in your multimeter.

Page 96

3 Multimeter Features

WARNING

CAUTION

Vsense

NOTE

Range

Auto

Detecting AC Voltage Presence (Vsense) (U1242C only)

The Vsense detector is a non-contact voltage detector that detects the presence of AC voltages nearby.

– You are advised to test on a known live circuit within the rated AC voltage

range of this multimeter before and after each use to ensure that the Vsense detector works.

– Voltage could still be present even if there is no Vsense alert ind ication.

Do not rely on the Vsense detector with shielded wires. Never touch live voltage or conductor without the necessary insulation protection, or power off the voltage source.

– The Vsense detector may be affected by differences in socket design,

insulation thickness, and insulation type.

You are advised to measure voltage by using test leads through the Z

LOW

AC V, or DC V function after using the Vsense function, even if there is no alert indication.

Press and hold for > 1 second to enable or disable the Vsense function (on

any position of the rotary switch except OFF).

If the presence of AC voltage is sensed, the multimeter’s beeper will sound, the

red LED indicator will light up, and alerts allow you to easily sense nearby AC voltage presence.

No resolution and accuracy of voltage measurement will be displayed in this mode.

Press to toggle the Vsense detector’s sensitivity between (high

sensitivity) or (low sensitivity).

96 Keysight U1241C/U1242C User’s Guide

will be displayed. The audible and visual

Page 97

Figure 3-1 High Vsense sensitivity display

NOTE

Multimeter Features 3

Figure 3-2 Low Vsense sensitivity display

– Place the top of the mul timeter (with the Vsense indicator) close to a

conductor when sensing for AC voltages (as low as 24 V in the setting).

– The low sensitivity setting can be used on flush mounted wall sockets or

outlets and various power strips or cords.

– The high sensitivity setting allows for AC voltage sensing on other styles of

recessed power connectors or sockets where the actual AC voltage is recessed within the connector itself.

Keysight U1241C/U1242C User’s Guide 97

Page 98

3 Multimeter Features

NOTE

Vsense

Making Relative Measurements (Null)

When making null measurements, also called relative, each reading is the difference between a null value (stored or measured) and the input signal.

One possible application is to increase the accuracy of a resistance measurement by nulling the test lead resistance. Nulling the leads is also particularly important prior to making capacitance measurements.

Null can be set for both auto and manual range settings, but an overload reading cannot be stored as a null value.

1 To activate the relative mode, press . The measurement value at the time

that when Null ( ) is enabled, is stored as the reference value.

Figure 3-3 Null display

2 Press again to view the stored reference value (

flashes). The display

will return to normal after 3 seconds.

3 To disable the Null function, press while the stored reference value is

shown.

98 Keysight U1241C/U1242C User’s Guide

Page 99

Multimeter Features 3

NOTE

Vsense

Display returns to normal after 3 seconds

Press to enable the Null function

Vsense

Press again to disable

the Null function

Vsense

Press

Vsense

Flashing

– In resistance measurement, the multimeter will read a non-zero value even

when the two test leads are in direct contact, because of the resistance of these leads. Use the null function to zero-adjust the display.

– For DC voltage measurements, the thermal effect will influence the accuracy

of the measurements. Short the test leads and press when the

displayed value is stable to zero-adjust the display.

Figure 3-4 Null operation

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3 Multimeter Features

MaxMin

MaxMinHzMaxMin

Capturing Maximum and Minimum Values (MaxMin)

The MaxMin operation stores the maximum, minimum, and average input values during a series of measurements.

When the input goes below the recorded minimum value or above the recorded maximum value, the multimeter beeps and records the new value. The elapsed time since the recording session was started is stored and shown on the display at the same time. The multimeter also calculates an average of all readings taken since the MaxMin mode was activated.

From the multimeter’s display, you can view the following statistical data for any set of readings:

– Max: highest reading since the MaxMin function was enabled

– Min: lowest reading since the MaxMin function was enabled

– Avg: average or mean of all readings since the MaxMin function was enabled

– MaxMinAvg: present reading (actual input signal value)

1 Press for > 1 second to enable the MaxMin operation.

Figure 3-5 MaxMin display

2 Press for > 1 second to exit the MaxMin operation.

3 Press again to cycle through the Min, Avg, MaxMinAvg (present), or

Max input values.

100 Keysight U1241C/U1242C User’s Guide

Keysight U1242C, U1241C User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Safety Symbols

Safety Considerations

Measurement Category

Environmental Conditions

Safety and Regulatory Information

Regulatory Markings

Waste Electrical and Electronic Equipment (WEEE) Directive 2002/ 96/EC

Product category

Sales and Technical Support

Table of Contents

List of Figures

List of Tables

1 Introduction

About This Manual

Documentation map

Safety notes

Preparing Your Multimeter

Check the shipment

Install the batteries

Turn on your multimeter

Automatic power off

Enabling the backlight

Selecting the range

Alerts and warnings during measurement

Adjusting the tilt stand

Remote communication

Power-on options

Your Multimeter in Brief

Overview

Rotary switch

Keypad

Display screen

Input terminals

Cleaning Your Multimeter

2 Making Measurements

Crest factor

Measuring AC Voltage

Measuring Harmonic Ratio (U1242C only)

Measuring DC Voltage

Measuring AC or DC mV

Measuring Resistance

Testing for Continuity

Testing Diodes

Measuring Capacitance

Measuring Frequency

Using the low pass frequency filter function for frequency measurements

Measuring Temperature

Scanning temperature measurements (U1242C only)

Measuring AC or DC Current

% Scale of 4-20 mA or 0-20 mA

3 Multimeter Features

Detecting AC Voltage Presence (Vsense) (U1242C only)

Making Relative Measurements (Null)

Capturing Maximum and Minimum Values (MaxMin)