reproduced 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.
Manual Part Number
U1241-90038
Edition
Edition 9, July 30, 2016
Printed in:
Printed in Malaysia
Published by:
Keysight Technologies
Bayan Lepas Free Industrial Zone,
11900 Penang, Malaysia
Technology Licenses
The hard ware 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, modify, 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.
2Keysight U1241AN User’s and Service Guide
Page 3
Safety Symbols
The following symbols on the instrument and in the documentation indicate
precautions which must be taken to maintain safe operation of the instrument.
Direct current (DC)Off (supply)
Alternating current (AC)On (supply)
Both direct and alternating currentCaution, risk of electric shock
Three-phase alternating current
Earth (ground) terminalCaution, hot surface
Protective conductor terminalOut position of a bi-stable push control
Caution, risk of danger (refer to this
manual for specific Warning or Caution
information)
Frame or chassis terminalIn position of a bi-stable push control
Equipotentiality
Equipment protected throughout by
double insulation or reinforced
insulation
CAT III
1000 V
CAT IV
600 V
Category III 1000 V overvoltage
protection
Category IV 600 V overvoltage
protection
Keysight U1241AN User’s and Service Guide3
Page 4
General Safety Information
WARNING
The following general safety precautions must be observed during all phases of
operation, service, and repair of this instrument. Failure to comply with these
precautions or with specific warnings elsewhere in this manual violates safety
standards of design, manufacture, and intended use of the instrument. 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.
– Observe all markings on the instrument before connecting any wiring to
the instrument.
– When working above 60 VDC, 30 VAC RMS, or 42.4 Vpeak, exercise
caution – such range poses a shock hazard.
– Do not measure more than the rated voltage (as marked on the
multimeter) between terminals, or between terminal and earth ground.
– Double-check the multimeter operation by measuring a known voltage.
– For current measurement, power off circuit power before connecting the
multimeter to the circuit. Always place the multimeter in series with the
circuit.
– When connecting probes, always connect the common test probe first.
When disconnecting probes, always disconnect the live test probe first.
– Detach test probes from the multimeter before you open the battery cover.
– Do not use the multimeter with the battery cover or part of the cover
removed or loose.
– Replace the battery as soon as the low battery indicator flashes on
screen. This is to avoid false readings, which may lead to possible electric
shock or personal injury.
– Do not operate the product in an explosive atmosphere or in the presence
of flammable gases or fumes.
– Inspect the case for cracks or missing plastic. Pay extra attention to the
insulation surrounding the connectors. Do not use the multimeter if it is
damaged.
4Keysight U1241AN User’s and Service Guide
Page 5
WARNING
– Inspect the test probes for damaged insulation or exposed metal, and
CAUTION
check for continuity. Do not use the test probe if it is damaged.
– To avoid arc explosion, make sure that the probe tip and probe tip
accessories are rated for the measurement environment. CAT II and CAT III
accessories must not be used in a CAT IV environment.
– Do not use repaired fuses or short-circuited fuse-holders. For continued
protection against fire, replace the line fuses only with fuses of the same
voltage and current rating and recommended type.
– Do not service or perform adjustments alone. Under certain condition,
hazardous voltages may exist, even with the equipment switched off. To
avoid dangerous electric shock, service personnel must not attempt
internal service or adjustment unless another person, capable of
rendering resuscitation or first aid, is present.
Do not substitute parts or modify equipment to avoid the danger of
–
introducing additional hazards. Return the product to Keysight Sales Office
for service and repair to ensure the safety features are maintained.
– Do not operate damaged equipment as the safety protection features
built into this product may have been impaired, either through physical
damage, excessive moisture, or any other reason. Remove power and do
not use the product until safe operation can be verified by service-trained
personnel. If necessary, return the product to Keysight Technologies
Sales and Service Office for service and repair to ensure the safety
features are maintained.
Keysight U1241AN User’s and Service Guide5
– Power off circuit power and discharge all high-voltage capacitors in the
circuit before you perform resistance and capacitance measurements or
continuity and diode tests.
– Use the correct terminals, function, and range for your measurements.
– Never measure voltage when current measurement is selected.
– Ensure proper insertion of battery in the multimeter, and follow the
correct polarity.
Page 6
Measurement Category
The U1241AN has a safety rating 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.
6Keysight U1241AN User’s and Service Guide
Page 7
Environmental Conditions
CAUTION
This instrument is designed for indoor use and in an area with low condensation
with use of standard or compatible test probes. The table below shows the
general environment requirements for this instrument.
Environmental conditionRequirement
Operating environmentFull accuracy at –10 °C to 55 °C
Operating relative humidity
Storage environment–40 °C to 70 °C
Altitude
Pollution degreePollution Degree 2
Full accuracy up to 80% RH for temperature up to
30 °C, decreasing linearly to 50% RH at 55 °C
Up to 2000 meters per IEC 61010-1
nd
Edition CAT III, 1000 V/IEC 61010-1 2
2
Edition CAT IV, 600 V
nd
– The Keysight U1241AN complies with the following safety and EMC
requirements:
– IEC 61010-1:2001 / EN61010-1:2001
– USA: ANSI/UL61010-1:2004
– Canada: CAN/CSA C22.2 No. 61010-1-04
– IEC 61326-1:2005/EN 61326-1:2006
– Canada: ICES-001:2004
– Australia/New Zealand: AS/NZS CISPR11:2004
– Compliance with IEC 61000-4-3 Radiated Immunity, Criteria A, may
require appropriate positioning of instrument test leads.
Keysight U1241AN User’s and Service Guide7
Page 8
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.
This instrument complies with the WEEE
Directive (2002/96/EC) marking
requirement. This affixed product label
indicates that you must not discard this
electrical or electronic product in
domestic household waste.
The CSA mark is a registered trademark
of the Canadian Standards Association.
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.
8Keysight U1241AN User’s and Service Guide
Page 9
Waste Electrical and Electronic Equipment (WEEE) Directive
2002/96/EC
This instrument complies with the WEEE Directive (2002/96/EC) marking
requirement. This affixed product label indicates that you must not discard this
electrical or electronic product in domestic household waste.
Product category:
With reference to the equipment types in the WEEE directive Annex 1, this
instrument is classified as a “Monitoring and Control Instrument” product.
The affixed product label is as shown below.
Do not dispose in domestic household waste.
To return this unwanted instrument, contact your nearest 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/handhelddmm
(product-specific information and support, software and
documentation updates)
– www.keysight.com/find/assist
(worldwide contact information for repair and service)
Keysight U1241AN User’s and Service Guide9
Page 10
In This Guide…
1Getting Started
This chapter introduces the key features and steps to get started with the
U1241AN handheld digital multimeter. This chapter also guides you through the
basics of the front panel operations.
2Features and Functions
This chapter contains detailed information on how to configure connections to
perform measurements using the U1241AN handheld digital multimeter.
3Default Settings Configurations
This chapter describes on how to change and configure the default settings of the
U1241AN handheld digital multimeter including data logging and other features.
4Service and Maintenance
This chapter provides you with warranty services, maintenance procedures, and
troubleshooting hints to solve general problems that you may encounter with the
instrument. Repair or service which are not covered in this manual should only be
performed by qualified service personnel. Please return to Keysight for product
exchange if the product fails within the warranty period.
5Performance Tests and Calibration
This chapter contains procedures of performance verification tests and calibration
adjustments. The performance tests is to ensure the multimeter is operating
within its published specifications.
6Specifications and Characteristics
For the characteristics and specifications of the U1241AN Handheld Digital
Multimeter, refer to the datasheet at http://literature.cdn.keysight.com/litweb/
pdf/5989-7040EN.pdf.
Keysight U1241AN Handheld Digital Multimeter
User’s and Service Guide
1Getting Started
Introduction 20
Checking the Shipping Contents 21
The Front Panel at a Glance 22
Adjusting Tilt Stand 22
The Annunciator at a Glance 23
The Keypad and Rotary Switch at a Glance 25
The Input Terminal at a Glance 26
This chapter introduces the key features and steps to get started with the
U1241AN handheld digital multimeter. This chapter also guides you through the
basics of the front panel operations.
19
Page 20
1Getting Started
Introduction
The U1241AN handheld digital multimeter key features are:
– DC and AC voltage measurements
– DC and AC current measurements
– True RMS measurement for both AC voltage and current
– Ambient temperature readout at secondary display with each measurement
– Resistance measurement up to 100 MΩ
– Diode and audible continuity tests
– Capacitance measurement up to 10 mF
– The percentage scale readout for 4–20 mA or 0–20 mA measurement
– Temperature test with selectable 0
– K-type temperature measurement
– MINMAX recording for minimum, maximum, and average readings
– Data Hold with manual or auto trigger modes
– Null/Relative function
readout
°C compensation (without ambient
temperature compensation)
– Auto or manual data logging memories
– Battery capacity indicator
– Adjustable brightness level of blue LED backlight display
– Closed case calibration
– 10,000 count precision true RMS digital multimeter, designed to meet EN/IEC
61010-1:2001 Category III 1000 V/Category IV 600 V Overvoltage Protection,
Pollution Degree 2 standards
20Keysight U1241AN User’s and Service Guide
Page 21
Checking the Shipping Contents
Verify that you have received the following items with your unit. If anything is
missing or damaged, please contact the nearest Keysight Sales Office.
Tab le 1-1List of standard items
TypeItems
U1241AN handheld digital multimeter
Four 1.5 V AAA alkaline batteries
Standard
Test leads
Product Reference CD-ROM
Certificate of Calibration
Getting Started1
Keysight U1241AN User’s and Service Guide21
Page 22
1Getting Started
Display
Keypad
Rotary switch
Input terminal
Pull the tilt stand outwards
to its maximum reach
(approximately 60°)
Bend the tip of the stand
Tilt stand at 60° Tilt stand at 30°
The Front Panel at a Glance
Figure 1-1U1241AN front panel
Adjusting Tilt Stand
Figure 1-2Tilt stand positions
22Keysight U1241AN User’s and Service Guide
Page 23
The Annunciator at a Glance
To view the full display, press and hold while turning the rotary switch
from OFF to any non-OFF position. Press any key to resume normal functionality
mode.
Figure 1-3U1241AN annunciator display
Getting Started1
Tab le 1-2General display annunciators
AnnunciatorDescriptionAnnunciatorDescription
21-segment analog bar graph displayData logging mode
Audible continuity for resistance and
diode function
Primary display Null math function
AC or DC measurement mode
Auto rangePrimary measurement units
Diode/test modeMeasurement range
Auto or manual for data logging mode
and data logging viewing mode
Secondary display (ambient temperature
display)
Thermocouple type for temperature
measurement
Keysight U1241AN User’s and Service Guide23
Page 24
1Getting Started
Tab le 1-2General display annunciators (continued)
AnnunciatorDescriptionAnnunciatorDescription
T1 temperature measurementLow battery indicator
Data holdAuto power off indicator
MINMAX record ing mode
Analog Bar Graph
When frequency is indicated on the primary display during voltage or current
measurement, the bar graph represents the voltage or current value. When
4–20 mA% scale or 0–20 mA% scale is indicated on the primary display, the bar
graph represents the current value. Each segment represents 500 or 50 counts
depending on the range indicated on the peak bar graph.
Temperature +T1 –T11000 Vrms < 0.3A short circuit current
1000 Vrms
1000 Vrms for short circuit current <0.3 AResistance (Ω)
To avoid damaging the device, do not exceed the rated input limit.
Keysight U1241AN User’s and Service Guide27
Page 28
1Getting Started
THIS PAGE HAS BEEN INTENTIONALLY LEFT BLANK.
28Keysight U1241AN User’s and Service Guide
Page 29
Keysight U1241AN Handheld Digital Multimeter
User’s and Service Guide
2Features and Functions
Measuring Voltage 30
Measuring Current (> 440 mA) 30
Measuring Current (< 440 mA) 31
Measuring % Scale of 4 – 20 mA 31
Measuring Frequency 32
Measuring Resistance and Testing Continuity 32
Testing Diodes 33
Measuring Capacitance 34
Measuring Temperature 35
MINMAX Recording 36
Data Hold (Trigger Hold) 37
Refresh Hold 37
Null (Relative) 38
Data Logging 39
Checking Battery Capacity 42
Alerts and Warning During Measurement 43
This chapter contains detailed information on how to configure connections to
perform measurements using the U1241AN handheld digital multimeter.
29
Page 30
2Features and Functions
WARNING
Press to select
AC vol tage
measurement mode.
Press to select
AC current
measurement mode.
Measuring Voltage
Ensure that terminal connections are correct for that particular
measurement before performing any measurement. To avoid damaging the
device, do not exceed the rated input limit.
Measuring DC voltageMeasuring AC voltage
Measuring Current (> 440 mA)
Measuring DC currentMeasuring AC current
30Keysight U1241AN User’s and Service Guide
Page 31
Measuring Current (< 440 mA)
NOTE
Press to select
AC current
measurement mode.
If the measured value is lower than 440 mA, use the mA or μA current
measurement mode.
Features and Functions2
Measuring % Scale of 4 – 20 mA
The percentage scale of 0–20 mA or
4–20 mA is selectable in setup mode.
Press
at
position
Keysight U1241AN User’s and Service Guide31
The percentage scale is indicated on
the primary display and the bar graph
indicates the current value. The 25%
scale readout represents DC 5 mA at
0–20 mA and DC 8 mA at 4–20mA.
Page 32
2Features and Functions
CAUTION
Measuring Frequency
Press
The frequency measurement is applicable
for AC voltage measurement.
The bar graph is used to indicate the
value of the AC voltage.
at
position
Alternatively, press to display the
value of the AC voltage. The multimeter
will return to the frequency measurement
display automatically after three seconds.
Measuring Resistance and Testing Continuity
Disconnect circuit power and discharge all high-voltage capacitors before
measuring resistance to prevent possible damage to the multimeter or the
device under test.
Measurement rangeBeeper sound threshold
Press at
position to enable the
continuity test
functions
100.00 Ω< 1 Ω
1000.0 Ω< 10 Ω
10.000 kΩ< 100 Ω
100.00 kΩ< 1 kΩ
1.0000 MΩ< 10 kΩ
10.000 MΩ< 100 kΩ
100.00 MΩ< 1 MΩ
32Keysight U1241AN User’s and Service Guide
Page 33
NOTE
Press button to select measurement range from 1 kΩ to 100 MΩ.
CAUTION
Reverse bias Forward bias
NOTE
Testing Diodes
Disconnect any circuit power and discharge all high-voltage capacitors
before testing diodes to prevent possible damage to the multimeter.
Features and Functions2
The multimeter can display forward bias diode of up to approximately 1.1 V.
Typical forward bias diode ranges between 0.3 to 0.8 V with audible beeper
sound.
Keysight U1241AN User’s and Service Guide33
Page 34
2Features and Functions
CAUTION
Measuring Capacitance
Disconnect any circuit power and discharge all high-voltage capacitors
before measuring capacitance to prevent possible damage to the multimeter
or the device under test. To confirm that the capacitors have been
discharged, use the DC voltage measurement function.
Measuring tips:
– For measuring capacitances
greater than 10,000 μF,
discharge the capacitor and
manually select a suitable
measurement range. This
will speed up measuring
time in order to obtain the
correct capacitance value.
– Ensure the polarity is correct
when measuring polarized
capacitors.
–For measuring small
capacitances, press
with the test leads open to
subtract the residual
capacitance of the
multimeter and leads.
34Keysight U1241AN User’s and Service Guide
Page 35
Measuring Temperature
CAUTION
– Do not bend the thermocouple leads at sharp angles. Repeated bending
over a period of time can break the leads.
– Do not contact the temperature sensor to any surface that has an energized
voltage or current source, such sources will pose a shock hazard.
Press at
function
Features and Functions2
Measuring tips:
– Clean the measurement
surface and remember to
disable the applied power.
– When measuring
temperature, move the
thermocouple along the
surface until you get the
highest/lowest temperature
reading.
– For quick measurement, use
the 0 °C compensation to see
the temperature variation of
the thermocouple sensor. The
0 °C compensation assists you
in measuring relative
temperature.
If you are working in a varied environment, where ambient temperature is not
constant, do the following:
1 Press for more than one second to enable 0 °C compensation. This
function allows a quick measurement of the relative temperature.
2 Avoid contact between the thermocouple probe and the measurement surface.
3 After a constant reading is obtained, press to set the reading as the
relative reference temperature.
4 Touch the measurement surface with the thermocouple probe.
5 Read the display for the relative temperature.
Keysight U1241AN User’s and Service Guide35
Page 36
2Features and Functions
NOTE
MINMAX Recording
1 Press for more than one second to enter MINMAX recording mode. The
multimeter is now in continuous mode or non-data hold (non-trigger) mode.
2 The beeper sounds when a new maximum or minimum value is recorded.
3 Press to scroll through maximum, minimum, or average present readings.
The MAX, MIN, AVG, or MAXMINAVG annunciator lights up correspondingly to
the displayed readings.
4 Press for more than one second to exit MINMAX Recording mode.
– The average value is the true average of all measured values taken in the
MINMAX recording mode.
– If an overload is recorded, the averaging function will stop and OL will be
displayed.
– The auto power off feature () is disabled in MINMAX recording mode.
36Keysight U1241AN User’s and Service Guide
Page 37
Data Hold (Trigger Hold)
NOTE
The data hold function allows you to freeze the displayed digital value.
1 Press to freeze the displayed value and to enter manual trigger mode.
Notice that the annunciator is displayed.
2 Press to trigger the freeze of the next value being measured. The
annunciator will flash before the new value is updated onto the display.
3 Press for more than one second to exit this mode.
Refresh Hold
You are required to activate the Refresh Hold in the setup mode.
1 Press to enter Refresh Hold mode. The present value will be held, and
the annunciator is displayed.
Features and Functions2
2 The multimeter is ready to hold new measuring value once the variation of
measuring value exceeds the setting of variation count, and the
annunciator is flashed.
3 The hold value will be updated until the measuring value is stable. The
annunciator will then stop flashing and an audible tone will sound to remind
you.
4 Press again to disable this function.
– For voltage, current, and capacitance measurements, the holding value will
not be updated if the reading is below 50 counts.
– For resistance and diode measurements, the holding value will not be
updated if the reading is in “OL” (open state).
– The holding value may not be updated if the reading does not reach stable
state for all measurements.
Keysight U1241AN User’s and Service Guide37
Page 38
2Features and Functions
NOTE
Null (Relative)
The Null function subtracts a stored value from the present measurement and
displays the difference between the two values.
1 Press to store the displayed reading as the reference value to be
subtracted from subsequent measurements and to set the display to zero. The
NULL annunciator is displayed.
2 Press to view the stored reference value. The NULL annunciator will
flash for three seconds before the display returns to zero. To exit this mode,
press while NULL is flashing on the display.
– In resistance measurement, the multimeter reads a non-zero value due to the
presence of test leads resistance. Use the Null function to zero-adjust the
effect of test lead resistance.
– In DC voltage measurement, the thermal effect will influence the accuracy.
Short the test leads and press once the displayed value is stable in
order to zero out the offset.
38Keysight U1241AN User’s and Service Guide
Page 39
Features and Functions2
Data Logging
The data logging function stores the data in non-volatile memory. Thereby, the
data remains saved when the multimeter is turned off. Data logging records only
the value on primary display. Two options of data logging are offered — Hand
(manual) logging and Interval (automatic) logging functions.
Tab le 2-1Functions available for data logging
FunctionModeRange
VoltageDC, AC1000 mV to 1000 V
CurrentDC, AC, % of mA1000 μA to 10 A
HzACAuto
ΩContinuity1000 Ω to 100 MΩ
Diode
1.1 V
Capacitance
TemperatureT1
Relative
Recording modeMAX, MIN, AVG, MAXMINAVG
Hold
Manual Logging
To enable the Hand (manual) logging function, select the Hand logging mode in
Setup mode.
1 Press (Log) for more than one second to store the present value and
function on the primary display to memory.
2 Press (Log) again for the next value that you want to save into memory,
see Figure 2-1.
1000 nF to 10 mF
Keysight U1241AN User’s and Service Guide39
Page 40
2Features and Functions
NOTE
NOTE
3 Press (Log) for more than one second to exit this mode.
Figure 2-1Manual logging display
The maximum data that can be stored is 100 entries. When the 100 entries are
filled, the FUL annunciator is indicated on the secondary display.
Interval Logging
To enable the Interval (automatic) logging function, select the Interval logging by
defining the interval setting in Setup mode.
1 Press (Log) for more than one second to store the present value and
function on the primary display to memory.
2 The reading automatically logs into the memory in every interval as preset in
Setup mode, see Figure 2-2.
3 Press (Log) for more than one second to exit this mode.
When interval (automatic) logging is enabled, all keypad operation is disabled,
except for the LOG function.
40Keysight U1241AN User’s and Service Guide
Page 41
Figure 2-2Interval logging display
NOTE
The maximum data that can be stored is 200 entries. When the 200 entries are
filled, the FUL annunciator is indicated on the secondary display.
Reviewing Logged Data
1 Press (View) for more than one second to enter the Log View mode. The
last recorded entry and last logging index are displayed on the secondary
display.
Features and Functions2
2 Press to scroll through the logged data. Press to select the first
record or press to select the last record for quick navigation.
3 Press to switch between hand (manual) and interval (automatic) logging
review mode.
4 Press (View) for more than one second to exit the Log View mode.
Removing Logged Data
Press (Log) for more than one second at the respective Log Review mode
(hand or interval) to clear all logged data in the memory.
Keysight U1241AN User’s and Service Guide41
Page 42
2Features and Functions
Checking Battery Capacity
The battery sign will flash when the battery voltage drops below 4.4 V. Once
the low battery sign is displayed, it is highly recommended to replace the batteries
immediately. See Chapter 4, “Battery Replacement” on page 50.
To check the battery capacity, see the following steps:
1 Press (BAT) for more than one second to view the battery capacity. The
multimeter will resume back to normal function automatically after three
seconds.
2 The primary display illustrates the flashing bAt annunciator and the bar graph
indicates the battery capacity in proportional percentage from 4.2 V (0%) to
6.0 V (100%).
Figure 2-3Battery capacity display
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Alerts and Warning During Measurement
WARNING
Overload Alert
For your safety, please be aware of the overload alert. When you are alerted,
immediately remove the test leads from the measuring source.
The multimeter provides an overload alert for voltage measurement in both auto
and manual range modes. The multimeter beeps periodically once the measuring
voltage exceeds 1100.0 V.
Input-A Warning Alert
The multimeter sounds an alerting beep when the test lead is inserted to the A
input terminal but the rotary switch is not set to the corresponding A location. The
display indicates a flashing AErr annunciator until the test lead is removed from
the A input terminal.
Features and Functions2
Input-mA Warning Alert
The multimeter sounds an alerting beep when the μA/mA input terminal detects a
voltage level of more than 1.6 V. The display indicates a flashing CErr annunciator
until the test lead is removed from the μA/mA input terminal.
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2Features and Functions
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Keysight U1241AN Handheld Digital Multimeter
User’s and Service Guide
3Default Settings
Configurations
Setting Configurations 46
This chapter describes on how to change and configure the default settings of the
U1241AN handheld digital multimeter including data logging and other features.
45
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3Default Settings Configurations
NOTE
Setting Configurations
1 Turn the multimeter OFF.
2 From the OFF position, press and hold (Setup) while turning the rotary
switch to any non-OFF position.
You will hear a beep when the multimeter is successfully in Setup mode. You
may then release the button.
To change a menu item setting in Setup mode, perform the following steps:
1 Press or to scroll through menu items.
2 Press or to scroll through available settings. See Table 3-1 on page 47
for the details of each available option.
3 Press (Save) to save the changes. These parameters remain in the
non-volatile memory.
4 Press and hold (Setup) for more than one second to exit Setup mode.
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Tab le 3-1Available setting options in Setup mode
n
Default Settings Configurations3
Menu itemAvailable setting options
SetupDescriptionSelectionDescription
OFFEnables Data Hold (manual trigger)
rHdTrigger hold
SCAPercentage scale
FrE
Minimum frequency
can be measured
100–1000
0–20 mA,
4–20 mA
0.5 Hz, 1 Hz,
2 Hz, 5 Hz
Sets variation count that determines Refresh Hold
(auto trigger)
Sets percentage scale readout for 0mA to 20 mA or
4 mA to 20 mA
Sets the minimum frequency that can be measured
in AC measurement mode
2400 Hz,
bEP
Frequency of beep
sound
1200 Hz,
600 Hz,
300 Hz
Sets frequency of beep sound of the multimeter
OFFDisables beep sound of multimeter
tYPESets thermocouple type to K-type
tP
Thermocouple
tYPE
[a]
Sets thermocouple type to J-type
tYPE mVSets 100 mV measurement for T1 input
HandEnables manual data logging
LogData logging
1–9999 s
Sets interval for automatic data logging from 1 to
9999 seconds. Press to toggle through the
digit to be adjusted.
APF
Auto power off
[a]
1–99 mSets timer in minutes for auto power off
OFFDisables auto power off
Default factory
setting
500
4–20 mA
0.5 Hz
2400 Hz
tYPE K
Hand
15 m
LitBacklight timer
1–99 s
Sets timer in seconds for auto turn-off for backlight
display
15
OFFDisables auto turn-off for backlight display
dAC
Default AC or DC for
voltage and current
measurements
dC, AC
Defines the preferred setup of AC or DC for voltage
and current measurement once multimeter is
turned on.
dC
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3Default Settings Configurations
n
n
Tab le 3-1Available setting options in Setup mode (continued)
Menu itemAvailable setting options
SetupDescriptionSelectionDescription
Resets the multimeter to the factory settings by
rStResetdFAU
pressing and holding for more than
1 second. A beep sound indicates the reset is
being done.
Sets temperature measurement to °C, pressing
d-CF
to change measurement unit to °F
d-FSets temperature measurement to °F
tP
Temperature
[b]
Sets temperature measurement to °F, pressing
d-FC
to change measurement unit to °C
d-CSets temperature measurement to °C
[a] To activate the multimeter after it has auto power off, press any button to resume back to respective functional mode.
[b] To view Temperature (tP) menu, press
for more than one second.
Default factory
setting
dFAU
d-CF
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Keysight U1241AN Handheld Digital Multimeter
User’s and Service Guide
4Service and Maintenance
General Maintenance 50
Battery Replacement 50
Fuse Replacement 52
Troubleshooting 54
Returning Instrument for Service 55
This chapter provides you with warranty services, maintenance procedures, and
troubleshooting hints to solve general problems that you may encounter with the
instrument. Repair or service which are not covered in this manual should only be
performed by qualified service personnel. Please return to Keysight for product
exchange if the product fails within the warranty period.
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4Service and Maintenance
WARNING
WARNING
General Maintenance
To avoid electrical shock or damage to the multimeter, ensure that no water
stays inside the casing.
Dirt or moisture in the terminals can distort readings. Cleaning steps are as
follows:
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.
Battery Replacement
Do not discharge the battery by shorting the battery or reverse the battery
polarity in any subjects.
The multimeter is powered by 6.0 V (1.5 V x 4 batteries), and uses only the
specified battery type. To ensure the specification specified, it is suggested to
replace the battery immediately when the low battery sign is displayed and
flashing. See the following procedures for battery replacement:
1 At the rear panel, turn the tilt stand to up side.
2 Unscrew the battery cover, notice the screw may not remove as loosed.
3 Lift and remove the battery cover to the direction of screw.
4 Replace the specified batteries and ensure the correct polarity of batteries.
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Service and Maintenance4
Battery cover screw
5 Reverse the procedures of opening the cover to close the battery cover.
Battery TypesANSI/NEDAIEC
Alkaline24ALR03
Zinc Chloride 24DR03
Figure 4-1Battery replacement
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4Service and Maintenance
NOTE
Fuse 1 (440 mA/1000 V)
Fuse Replacement
You are recommended to use clean/dry gloves when performing fuse
replacement. Do not touch any components except the fuse and plastic parts.
No recalibration is required after replacing the fuse.
1 Turn the multimeter off and disconnect the test leads from external
equipment.
2 Loosen the four screws at the rear panel, lift and remove the cover.
3 Gently remove the defective Fuse 1 by prying one end of the fuse and removing
it out of the fuse bracket, see Figure 4-2 on page 52.
4 Replace a new fuse of the same size and rating into the center of the fuse
holder.
Figure 4-2Fuse 1 replacement
5 If you want to replace a defective Fuse 2, remove Fuse 1 prior to removing the
Fuse 2. Loosen the four screws (shown in Figure 4-3 on page 53) to lift and
remove the circuit board from top case.
6 Gently remove the defective Fuse 2 by prying one end of the fuse loose and
removing it out of the fuse bracket, see Figure 4-3 on page 53.
7 Replace a new fuse of the same size and rating into the center of the fuse
holder.
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Service and Maintenance4
Fuse 2 (11 A/1000 V)
Rotary switch
Figure 4-3Fuse 2 replacement
8 Ensure that the rotary switch position is aligned with the align marking on the
top case and circuit board switch stay on the OFF position.
9 Then refasten the circuit board and the bottom cover respectively.
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4Service and Maintenance
WARNING
Troubleshooting
To avoid electrical shock, do not perform any service unless you are qualified
to do so.
If the instrument fails to operate, check the batteries and test leads, and replace
them if necessary. If the instrument still does not function, check the identification
procedures as described in Table 4 -1.
Tab le 4-1Basic troubleshooting hints
MalfunctionIdentification
No LCD display after
power ON
No beeper toneCheck setup mode and verify if the beeper is set to OFF. Then select the desired driving frequency.
Failed on current
measurement
Check the battery polarity and replace batteries if necessary. Ensure that the replaced batteries are new
batteries, it is recommended not to mix old batteries with new batteries.
Check the fuse.
When servicing, use the specified replacement parts only. The Table 4-2 shows
the replacement part numbers.
Tab le 4-2List of replacement part number
Part numberDescription
U1241-44407U1241AN front housing
U1241-64401Bottom case and lens assembly
U1241-46401Battery cover
U1241-44701Multimeter stand
U1241-60002LCD display
2110-1400Fast blow fuse 1000 V, 0.44 A (10 mm x 35 mm)
2110-1402Fast blow fuse 1000 V, 11 A (10 mm x 35 mm)
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Returning Instrument for Service
NOTE
Before shipping your instrument for repair or replacement, Keysight recommends
that you acquire the shipping instructions from the Keysight Technologies Service
Center. A clear understanding of the shipping instructions is necessary to secure
your product for shipment.
1 Write the following information on a tag and if attach to the instrument.
– Name and address of owner
– Instrument model number
– Instrument serial number
– Description of the service required or failure indications
2 Remove all accessories from the instrument. Do not include accessories unless
they are associated with the failure symptoms.
3 Protect the instrument by wrapping it in plastic or heavy paper.
4 Pack the instrument in foam or other shock absorbing material and place it in a
strong shipping container.
You are recommended to use the original shipping material or order materials
from a Keysight Technologies Sales Office. If both options are not available,
place 8 cm to 10 cm (3 inches to 4 inches) of shock-absorbing and static-free
packaging material around the instrument to avoid movement during shipping.
5 Seal the shipping container securely.
Service and Maintenance4
6 Mark the shipping container as FRAGILE.
In the ensuing correspondence, refer to the instrument by its model number
and full serial number.
Keysight suggests that you always insure your shipments.
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Keysight U1241AN Handheld Digital Multimeter
User’s and Service Guide
5Performance Tests and
Calibration
Calibration Overview 58
Recommended Test Equipment 59
Basic Operating Test 60
Calibration Process 62
Test Considerations 63
Performance Verification Tests 64
Calibration Security 68
Adjustment Considerations 71
Calibration Adjustments 73
Calibration Count 79
Calibration Errors 80
This chapter contains procedures of performance verification tests and calibration
adjustments. The performance tests is to ensure the multimeter is operating
within its published specifications.
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5Performance Tests and Calibration
NOTE
Calibration Overview
Ensure that you have read “Test Considerations” on page 63 before calibrating
the multimeter.
Closed-case Electronic Calibration
The multimeter features closed-case electronic calibration. No internal
mechanical adjustments are required. The multimeter calculates correction
factors based upon the input reference value you set. The new correction factors
are stored in non-volatile memory until the next calibration adjustment is
performed. Non-volatile EEPROM calibration memory does not change when
power has been off.
Calibration Interval
A 2-year interval is adequate for most applications. Keysight does not recommend
extending calibration intervals beyond 2 years for any application.
Adjustment is Recommended
Specifications are only guaranteed within the period stated from the last
adjustment. Whatever calibration interval you select, Keysight recommends that
complete re-adjustment should always be performed at the calibration interval.
This will assure that the U1241AN will remain within specification for the next
calibration interval. This criteria for re-adjustment provides the best long–term
stability. Performance data is measured during performance verification tests and
does not guarantee that the multimeter will operate within the test limits unless
the adjustment is performed.
Refer to“Calibration Count” on page 79to verify that all adjustments have been
performed.
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Performance Tests and Calibration5
Recommended Test Equipment
The test equipment recommended for the performance verification and
adjustment procedures is listed below. If the exact equipment is not available,
substitute the calibration standards of equivalent accuracy.
Basic Operating Test is used to test the basic operability of the multimeter. Repair
is required if the multimeter fails the Basic Operating Test.
Backlight test
To test the backlight function, press to turn backlight ON at medium level
of brightness intensity. Press again to toggle the highest level of brightness
intensity. The backlight turns OFF automatically after setting period. Alternatively,
you can press for the third time to turn the backlight OFF.
Testing the display
To view all segments of the display, press and hold the button while turning
the rotary switch from OFF to any non-OFF position. Compare the display with the
Figure 5-1.
Figure 5-1Annunciator display
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Input-A Terminal Test
NOTE
This test determines if the input warning of the A current terminal test is
functioning properly. The multimeter sounds an alerting beep when the test lead
is inserted to the A input terminal but the rotary switch is not set to the
corresponding A location. The display indicates a flashing AErr annunciator until
the test lead is removed from the A input terminal.
Input-mA Terminal Alert Test
This test determines if the detected input voltage level is within the accepted
boundaries when the μA/mA input terminal is connected. The multimeter sounds
an alerting beep when the μA/mA input terminal detects a voltage level of higher
than 1.6 V. The display indicates a flashing CErr annunciator until the test lead is
removed from the μA/mA input terminal.
The alerting beep will continue to function even if the beep function is disabled.
Performance Tests and Calibration5
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5Performance Tests and Calibration
Calibration Process
1 Prior to performing the verification tests, see “Test Considerations” on
page 63.
2 Perform the verification tests to characterize the multimeter, see “Performance
Verification Tests” on page 64.
3 Unsecure the multimeter for calibration, see “Calibration Security” on page 68.
4 Prior to performing the adjustments, see “Adjustment Considerations” on
page 71.
5 Perform the adjustment procedures, see “Calibration Adjustments” on
page 73.
6 Secure the multimeter against unauthorized calibration, see “Exiting
Adjustment Mode” on page 78. Ensure that the multimeter has quit the
Adjustment Mode and turned off.
7 Record the new security code and calibration count in the multimeter’s
maintenance records.
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Test Considerations
Error may be induced by AC signals that are present on the input leads. Long test
leads can also act as an antenna causing pick-up of AC signals.
For optimum performance, all procedures should comply with the following
recommendations:
– Ensure that the calibration ambient temperature is stable and between 18 °C
and 28 °C. Ideally the calibration should be performed at 23 °C ± 2 °C.
– Ensure that the ambient relative humidity (RH) is less than 80%.
– Ensure that the low battery indicator does not appear during the performance
verification test. If it does, replace the batteries to avoid any inaccurate
reading.
– During temperature performance verification test, ensure that the multimeter
has been switched ON and placed in the test environment for at least one hour
with a J/K-type thermo-couple connected between the multimeter and
calibration source.
– Allow one minute warm-up period with a Shorting Plug connected to the V
and COM input terminals.
– Use shielded twisted pair Teflon-insulated cables to reduce settling and noise
errors. Keep the input cables as short as possible.
Performance Tests and Calibration5
– Connect the input cable shields to earth ground. Except where noted in the
procedures, connect the calibrator LO source to earth ground at the calibrator.
It is important that the LO to earth ground connection be made at only one
place in the circuit to avoid ground loops.
During DC voltage, DC current, and resistance gain verification measurements,
ensure that the calibrator's “0” output is correct. It is recommended to set the
offset for each range of the measuring function being verified.
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5Performance Tests and Calibration
NOTE
Input Connections
Test connections to the multimeter are best accomplished using the K-type
thermocouple wire and mini-connectors for temperature measurement. The
J-type thermocouple wire and mini-connectors can also be used for temperature
measurements. Shielded, twisted-pair, Teflon interconnect cables of minimum
length are recommended between the calibrator and the multimeter. Cable
shields should be earth ground referenced. This configuration is recommended for
optimal noises and settling time performance during calibration.
Performance Verification Tests
The performance verification tests are recommended as acceptance tests when
you first receive the multimeter. The acceptance test results should be compared
against the one year test limits. After acceptance, you should repeat the
performance verification tests at every calibration interval.
If the multimeter fails performance verification, adjustment or repair is required.
Adjustment is recommended at every calibration interval. If no adjustment is
being performed, it is highly recommended to establish a ‘guard band’, using not
more than 80% of the specifications, as the verification limits.
Users are highly recommended to read the “Test Considerations” on page 63
before performing performance verification tests.
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Performance Tests and Calibration5
Tab le 5-2Verification tests
StepTest FunctionRange5520A Output
1000 mV1000.0 mV± 1.1 mV
Turn the rotary switch to
1
position
10 V10.000 V± 11 mV
100 V100.00 V± 110 mV
1000 V1000.0 V± 1.1 V
1000.0 mV, 1 kHz± 10.4 mV
Error from nominal
1 year
U1241AN
2
Press to go to function
3
Press to go to frequency mode
4
Turn the rotary switch to position
1000 mV
10 V
100 V
1000 V
100 Hz1.000 V, 70 Hz± 31 mHz
1000 Hz1.000 V, 1000 Hz± 400 mHz
10 kHz1.000 V, 2 kHz± 1.6 Hz
Diode1.000 V± 5 mV
1000.0 mV, 2.5 kHz± 20.4 mV
1000.0 mV, 20 kHz± 20.4 mV
10.000 V, 1 kHz± 104 mV
10.000 V, 2.5 kHz± 204 mV
10.000 V, 20 kHz± 204 mV
100.00 V, 1 kHz± 1.04 V
100.00 V, 2.5 kHz± 2.04 V
100.00 V, 20 kHz± 3.03 V
1000.0 V, 1 kHz± 10.4 V
1000.0 V, 2.5 kHz± 30.3 V
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5Performance Tests and Calibration
Tab le 5-2Verification tests (continued)
StepTest FunctionRange5520A Output
100 Ω100.00 Ω
1000 Ω1000.0 Ω
10 kΩ10.000 kΩ
5
Turn the rotary switch to position
100 kΩ100.00 kΩ± 330 Ω
1000 kΩ1000.0 kΩ± 3.3 kΩ
10 MΩ10.000 MΩ± 62 kΩ
100 MΩ100.00 MΩ
1000 nF1000.0 nF± 10.3 nF
10 µF10.000 µF± 0.103 µF
Error from nominal
1 year
U1241AN
± 3.3 Ω
± 33 Ω
[a]
[a]
[a]
[b]
± 0.33 Ω
± 1.53 MΩ
6
Turn the rotary switch to position
100 µF100.00 µF± 1.03 µF
1000 µF1000.0 µF± 10.3 µF
10 mF10.000 mF0.103 mF
1000 µA1000.0 µA± 2.3 µA
7
Turn the rotary switch to position
10000 µA10000 µA± 23 µA
1000 µA1000.0 µA, 2 kHz± 10.2 µA
8
Press to go to function
10000 µA10000 µA, 2 kHz± 102 µA
100 mA100.00 mA± 0.23 mA
9
Turn the rotary switch to position
440 mA
400.0 mA
[c]
± 1.1 mA
100 mA100.00 mA, 2 kHz± 1.02 mA
10
Press to go to function
11
Turn the rotary switch to position
12
Press to go to function
13
Turn the rotary switch to position
440 mA
10 A
10 A
100 mV100.00 mV± 0.11 mV
400 mA
10.000 A
10.000 A
[c]
, 2 kHz
[d]
[d]
, 2 kHz
± 4.2 mA
± 33 mA
± 102 mA
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Performance Tests and Calibration5
Tab le 5-2Verification tests (continued)
StepTest FunctionRange5520A Output
100.00 mV, 1 kHz± 1.04 mV
14
Press to go to function
100 mV
100.00 mV, 2.5 kHz± 2.04 mV
100.00 mV, 20 kHz± 2.04 mV
Error from nominal
1 year
U1241AN
15
Press to go to T1 function
[e]
–40 ºC until
[f]
1000 ºC
0 ºC± 1ºC
1000 ºC± 11ºC
[a] The accuracy of 100 Ω to 10 kΩ are specified after math Null, that is used to subtract the test lead resistance and the thermal effect.
[b] For the range of 100 MΩ, the RH is specified for <60%.
[c] Current can be measured from 50 mA to 440 mA continuously. An addition of 0.2% to the specified accuracy when measuring a signal greater
than 440 mA to 1100 mA for 30 seconds maximum. After measuring > 440 mA current, cool down the multimeter for twice the measuring
time taken before proceeding for low current measurement.
[d] Current can be measured from 0.5 A up to 10 A continuously with the maximum opera ting temperature of 50 ºC. An addition 0.3% needs to be
added to the specified accuracy if the signal measured is in the range of 10 A to 19.999 A for 15 seconds maximum. After measuring a current
of > 10 A, leave the multimeter to cool down for 60 seconds before applying low current measurement.
[e] — Set both Fluke 5520A and multimeter to internal reference.
— Prior to performing measurements, connect one end of the K-type thermocouple (with miniature TC connector on both ends) to the 5520A
TC output, and the other end to a precision thermometer to verify that the source outputs the desired value. Adjust the source accordingly
if necessary.
— To perform the measurement, connect one end of the K-type thermocouple (with miniature TC connector on both ends) to the 5520A TC
output, and the other end to the multimeter via a TC-to-banana adapter. Allow at least 1 hour for the multimeter to stabilize.
[f] The multimeter should be ON for at least 1 hour before measurements are taken. The accuracy does not include the tolerance of the
thermocouple probe. When measuring temperature with respect to any temperature calibrator, set both the calibrator and multimeter with
external reference (without internal ambient compensation 0 ºC). If both calibrator and multimeter are set with internal reference (with
internal ambient compensation), deviation may be present between the readings of the calibrator and multimeter.
–40 ºC± 1.4 ºC
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5Performance Tests and Calibration
NOTE
Calibration Security
The calibration security code prevents accidental or unauthorized adjustments to
the multimeter. The multimeter is secured when the multimeter is shipped from
factory. Before performing any adjustment to the multimeter, you are required to
unsecure the multimeter by entering the correct security code (see “Unsecuring
the Multimeter for Calibration” on page 68). The security code may contain up to
4 numeric characters.
You can unsecure and change the security code from the multimeter front panel.
If you forgot your security code, see “Unsecuring the multimeter without the
security code” on page 70.
Unsecuring the Multimeter for Calibration
Before performing adjustment to the multimeter, you are required to unsecure the
multimeter by entering the correct security code. The security code is set to 1234
when the multimeter is shipped from the factory. The security code is stored in
non-volatile memory, and does not change when power is off.
Unsecuring the multimeter from the front panel
1 Turn the rotary switch to .
2 Press and simultaneously to enter the Calibration Security Code
entry mode. The primary display shows 5555 and the secondary display
shows SEU.
3 Press or to step each character in the code. Press or to change
the value of the selected character.
4 Press (Save) when done.
5 If the correct security code is entered, the secondary display will show “PAS”.
If an invalid code is entered, the multimeter will shows error code “E02” on the
secondary display for approximately 3 seconds before returning to the
Calibration Security entry mode.
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Performance Tests and Calibration5
Changing the multimeter calibration security code from the front panel
1 When the multimeter is in the unsecured mode, press button for more
than one second to enter Calibration Security Code setting mode.
2 The factory default calibration security code 1234 will be displayed on primary
display.
3 Press or to step each character in the code. Press or to change
the value of the selected character.
4 Press (Save) button, to store new calibration security code.
5 If the new calibration security code has been successfully stored, the
secondary display will show PASS. If the new code failed to save, the
multimeter will shows error code E07 on the secondary display for
approximately 3 seconds before returning to the Calibration Security Code
setting mode.
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5Performance Tests and Calibration
Unsecuring the multimeter without the security code
1 Record the last 4 digit serial numbers of the multimeter.
2 Turn the rotary switch to .
3 Press and simultaneously to enter the Calibration Security Code
entry mode. The primary display shows 5555 and the secondary display shows
SEC.
4 Press for more than one second to enter Set Default Security Code
mode. The secondary display shows SEr and primary display shows “5555”.
5 Press or to step each character in the code. Press and to
change the value of the selected character.
6 Set the last 4 digit serial number of the multimeter. Press (Save) to
confirm the entry.
7 If the 4 digit serial number entered is correct, the secondary display will show
PAS. If an invalid code is entered, the multimeter will shows error code E03.
Ensure that the last 4 digit serial number is entered correctly and repeat the
step 1 to 7.
Using the Front Panel for Adjustments
This section describes the process used to perform adjustments from the front
panel.
Selecting the Adjustment Mode
Unsecure the multimeter, see “Unsecuring the Multimeter for Calibration” on
page 68 or “Unsecuring the multimeter without the security code” on page 70.
Once the multimeter has been unsecured, the reference value will be indicated on
the primary display.
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Entering Adjustment Values
NOTE
NOTE
1 Press and to step through each character in the primary display.
2 Press and to change the value of the corresponding character from
digits 0 through 9.
3 Apply the respective corresponding input signal from the recommended test
equipment in Table 5 -1.
4 Press (Save) when done to start calibration.
Ensure that the accuracy of the input signal adheres to the Valid Adjustment
Input Values in Table 5-5.
Adjustment Considerations
After each adjustment, the secondary display shows PAS. If the calibration fails,
the multimeter sounds a beep, and an error number is shown in the secondary
display. Calibration error messages are described in “Calibration Errors” on
page 80.
Performance Tests and Calibration5
1 Allow the multimeter to warm up and stabilize for five minutes before
performing the adjustments.
2 Assure that the low battery indicator does not appear during the adjustment.
Replace the batteries to avoid inaccurate readings.
3 Consider the thermal effects of the test leads connected to the calibrator and
multimeter. It is recommended to wait for one minute before start performing
the calibration.
4 During ambient temperature adjustment, ensure that the multimeter has been
turned on for at least one hour with K-type thermocouple connected between
the multimeter and calibration source.
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5Performance Tests and Calibration
CAUTION
Do not power off the multimeter during ad justments, as this may delete the
calibration memory for the present function.
Valid Adjustment Input Values
Adjustment can be accomplished using the following input values below.
Tab le 5-3Valid adjustment input values
FunctionRangeValid Input Reference Val ues
1000 mV, 10 V, 100 V, 1000 V0.9 to 1.1 x full scale
1000 mV, 10 V, 100 V, 1000 V0.9 to 1.1 x full scale
1 V0.9 to 1.1 x full scale
1000 Ω, 10 kΩ, 100 kΩ,
1000 kΩ, 10 MΩ
1000 nF, 10 μF, 100 μF, 1000 μF, 10 mF0.9 to 1.1 x full scale
1000 μA, 10000 μA0.9 to 1.1 x full scale
100 mA, 1000 mA0.9 to 1.1 x full scale
10 A0.9 to 1.1 x full scale
0.9 to 1.1 x full scale
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Performance Tests and Calibration5
CAUTION
NOTE
Tab le 5-3Valid adjustment input values (continued)
FunctionRangeValid Input Reference Val ues
T10 °C
DCmV
(T1)
100 mV0.9 to 1.1 x full scale
The minimum AC current output of the Fluke 5520A calibrator is 29 µA.
Ensure that at least 50
Calibration Adjustments
Review the Test Considerations and Ad justment Considerations before
beginning the adjustment procedures.
1 Turn the rotary switch to the respective test function position, as shown in
Table 5-3.
2 After unsecuring the multimeter, the multimeter will go into the adjustment
mode, see “Unsecuring the Multimeter for Calibration” on page 68.
3 The primary display will show the reference value of the calibration items
(Cal Item). Configure each Cal Item shown in the input reference values in
Table 5-3.
Ensure that 0 °C with ambient compensation is
provided
µA is set at the calibrator source of AC µA.
4 Use the and arrow keys to select the calibration range (Cal Range).
5 Apply the input signal as shown in the Input Reference Value column of the
Table 5-3. The bar graph will display the input reading. There is no bar graph
display for temperature adjustment.
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5Performance Tests and Calibration
NOTE
NOTE
You are highly recommended to complete the adjustments in the same order as
shown in Table 5-3.
6 Enter the actual applied input, see “Entering Adjustment Values” on page 71.
7 Press to start the adjustments. The CAL flashes in the secondary display
indicating the calibration is in progress.
8 Upon completion of each adjustment value, the secondary display will show
PAS. If the adjustment failed, the multimeter will sound a long beep and the
calibration error number appears in the secondary display. The primary display
remains at the current Cal Item.
If the adjustment failed, check the input value, range, function, and entered
adjustment value and repeat the adjustment steps.
9 Turn the rotary switch to the next function according to the Test Function
column shown in Table 5-3. Repeat step 3 to step 8 for each adjustment point
shown in the calibration adjustment, see Table 5-4.
10 Verify the adjustments using the “Performance Verification Tests” on page 64.
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Tab le 5-4Calibration ad justments
Performance Tests and Calibration5
StepTest functionCal rangeInput reference value
Dual banana plug with
1
Turn the rotary switch to position
2
Press to go to function
Short
1000 mV1 V1000.0 mV
10 V10 V10.000 V
100 V100 V100.00 V
1000 V1000 V1000.0 V
1000 mV
10 V
100 V
copper wires short
between two terminals
30 mV, 70 Hz30.0 mV
1000 mV, 70 Hz1000.0 mV
1000 mV, 10 kHz1000.0 mV
0.5 V, 70 Hz0.500 V
10 V, 70 Hz10.000 V
10 V, 10 kHz10.000 V
5 V, 70 Hz5.00 V
100 V, 70 Hz100.00 V
Cal item
U1241AN
SHrt
100 V, 2.5 kHz100.00 V
50 V, 70 Hz50.0 V
3
Turn the rotary switch to position
1000 V
Short
1 V1 V1.000 V
1000 V, 70 Hz1000.0 V
1000V, 1 kHz1000.0 V
Dual banana plug with
copper wires short
between two terminals
SHrt
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5Performance Tests and Calibration
Tab le 5-4Calibration adjustments (continued)
StepTest functionCal rangeInput reference value
Dual banana plug with
4
Turn the rotary switch to position
5
Turn the rotary switch to position
Short
10 MΩ
1000 kΩ1000 kΩ1000.0 kΩ
100 kΩ100 kΩ100.00 kΩ
10 kΩ10 kΩ10.000 kΩ
1000 Ω1000 Ω1000 Ω
Open
1000 nF
10 μF10 μF10.000 μF
copper wires short
between two terminals
Input terminals open
(remove all test leads and
shorting plugs from input
terminals)
10 MΩ10.000 MΩ
Input terminals open
(remove all test leads and
shorting plugs from input
terminals)
400 nF400.0 nF
1000 nF1000.0 nF
Cal item
U1241AN
SHrt
oPEn
oPEn
100 μF100 μF100.00 μF
1000 μF1000 μF1000.0 μF
10 mF10 mF10.000 mF
Input terminals open
(remove all test leads and
shorting plugs from input
terminals)
oPEn
6
Turn the rotary switch to position
Open
1000 μA1000 μA1000.0 μA
10000 μA10000 μA10000 μA
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Tab le 5-4Calibration ad justments (continued)
Performance Tests and Calibration5
StepTest functionCal rangeInput reference value
50 μA, 70 Hz50.0 μA
Press to go to function
7
8
Turn the rotary switch to
9
Press to go to function
1000 μA
10000 μA
Open
position
100 mA100 mA100.00 mA
1000 mA320 mA320.0 mA
100 mA
1000 mA
100 μA, 70 Hz100.0 μA
1000 μA, 70 Hz1000.0 μA
1000 μA, 70 Hz1000 μA
10000 μA, 70 Hz10000 μA
Input terminals open
(remove all test leads and
shorting plugs from input
terminals)
5 mA, 70 Hz5.00 mA
10 mA, 70 Hz10.00 mA
100 mA, 70 Hz100.00 mA
100 mA, 70 Hz100.0 mA
320 mA, 70 Hz320.0 mA
Cal item
U1241AN
oPEn
Move the test lead from “μA.mA” and “COM” terminal to “A” and “COM” terminal
Caution: Connect the calibrator to the multimeter's “A” and “COM” terminal before applying 10 A
Input terminals open
(remove all test leads and
shorting plugs from input
terminals)
oPEn
10
Turn the rotary switch to position
Open
10 A10 A10.000 A
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5Performance Tests and Calibration
Tab le 5-4Calibration adjustments (continued)
StepTest functionCal rangeInput reference value
0.5 A, 70 Hz0.500 A
11
Press to go to function
12
Turn the rotary switch to position
13
Press to go to func tion
14
Press to go to
[a] — Set the 5520A to internal reference.
— Prior to performing adjustment, connect one end of the K-type thermocouple (with miniature TC connector on both ends) to the 5520A TC
output, and the other end to a precision thermometer to verify that the source outputs the desired value. Adjust the source accordingly if
necessary.
— To perform the adjustment, connect one end of the K-type thermocouple (with miniature TC connector on both ends) to the 5520A TC
output, and the other end to the multimeter via a TC-to-banana adapter. Allow at least 1 hour for the multimeter to stabilize.
T1 function
[a]
10 A
Short
100 mV100 mV100.00 mV
100 mV
K-type0 ºC000.0 ºC
1 A, 70 Hz1.000 A
10 A, 70 Hz10.000 A
Dual banana plug with
copper wires short
between two terminals
3 mV, 70 Hz 3.00 mV
100 mV, 70 Hz100.00 mV
Cal item
U1241AN
SHrt
Exiting Adjustment Mode
1 Remove all shorting plugs and connectors from the multimeter.
2 Record the new Calibration Count, see “Calibration Count” on page 79.
3 Press and simultaneously to exit the Adjustment Mode. Power off
and on the multimeter to return to normal measurement mode and secured.
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Calibration Count
NOTE
The multimeter provides the calibration count information for you to access
through front panel operation. Note that the multimeter was calibrated prior to
shipping out to users.
You are recommended to record the initial value of the calibration count once
receiving the multimeter.
The count value increases by one for each calibration point, from 0000 up to the
maximum of 19999. After the maximum count, the calibration count will reset to
0. The calibration count can be read from the front panel after the multimeter has
been unsecured:
1 In adjustment mode, press and hold for more than one second to view
the calibration count viewing mode. The primary display indicates the
calibration count value while the secondary display indicates “Cnt”.
2 Take note of the calibration count to keep track of the number of calibration
counts that has been performed.
Performance Tests and Calibration5
3 Press and hold for more than one second to exit the calibration count
mode.
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5Performance Tests and Calibration
Calibration Errors
The following error codes indicate failures that may occur during a calibration.
The error code is displayed on the secondary display.
Tab le 5-5Calibration error codes
CodeDescriptions
200Calibration error: Calibration mode is secured
E02Calibration error: Invalid secure code
E03Calibration error: Invalid serial number code
E04Calibration error: Calibration aborted
E05Calibration error: Value out of range
E06Calibration error: Signal measurement out of range
E07Calibration error: Frequency out of range
E08EEPROM write failure
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Keysight U1241AN Handheld Digital Multimeter
User’s and Service Guide
6Specifications and
Characteristics
For the characteristics and specifications of the U1241AN Handheld Digital
Multimeter, refer to the datasheet at http://literature.cdn.keysight.com/litweb/