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Service and Maintenance

Keysight U1270 Series Service Guide

Fuse Replacement

The current input terminals of your multimeter are fuse protected. The fuses are

located next to the battery compartment.
– The

µA mA

terminal is protected by a 10

35 mm 440 mA/1000 V 30 kA

fast-acting fuse (Fuse 1).

– The

terminal is protected by a 10

38 mm 11 A/1000 V 30 kA fast-acting

fuse (Fuse 2).

If you are certain that the fuse is faulty, replace it with one of the same size and

rating.

1 Open the battery cover.

Lift the tilt stand and loosen screws with a suitable

Phillips screwdriver and remove the battery cover.

2 Locate the faulty fuse.

Fuse 1 (see

Figure 2-3

) is located to the right of

batteries, and Fuse 2 (see

Figure 2-4

) is located at the bottom of the batteries.

See

Figure 2-5

for the specific location, size, and ratings of Fuse 1 and 2.

Gently remove the defective fuse by prying one end of the fuse with a flathead

screwdriver and removing it out of the fuse bracket. Replace a new fuse of the

same size and rating into the center of the fuse holder.

3 Close the batter cover.

Place the battery cover back in its original position and

tighten the screws.

NOTE

No recalibration is required after replacing the fuse.

CAUTION

Before you proceed with the fuse replacement, remove all cable connections

to the terminals and ensure that the rotary switch is at the OFF position.

Summary of Contents for U1271A

Page 1: ...Keysight U1270 Series Handheld Digital Multimeters Service Guide ...

Page 2: ...hts 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 ...

Page 3: ...Direct current DC Caution risk of electric shock Alternating current AC Caution risk of danger refer to this manual for specific Warning or Caution information Both direct and alternating current Category III 1000 V overvoltage protection Earth ground terminal Category IV 600 V overvoltage protection Equipment protected throughout by double insulation or reinforced insulation CAT III 1000 V CAT IV...

Page 4: ...larity markings before you insert the batteries to ensure proper insertion of the batteries in the meter You are advised to use low leakage batteries when changing to new batteries Please remember to remove the batteries when the meter is not in use for a long period of time Warning on the risk of battery leakage To avoid damage to the instrument from battery leakage Always remove dead batteries i...

Page 5: ...e measurement Voltages measured are usually greater than what are indicated on the multimeter as the voltages with higher frequencies have been filtered through the LPF function Do not use the ZLOW low input impedance function U1272A U1273A and U1273AX only to measure voltages in circuits that could be damaged by this function s low input impedance of 2 kΩ When using the probes keep your fingers b...

Page 6: ...es 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 moto...

Page 7: ...hium batteries Storage condition 40 C to 70 C Humidity Operating condition Maximum 80 RH at 40 C non condensing Minimum 50 RH at 40 C non condensing Storage condition Up to 95 RH at 40 C non condensing Altitude Up to 3000 m Pollution degree Pollution degree II NOTE The U1270 Series Handheld Digital Multimeters comply with the following safety and EMC requirements Safety EN IEC 61010 1 2001 ANSI UL...

Page 8: ...2 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 Cana...

Page 9: ...onitoring 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 sup...

Page 10: ...10 Keysight U1270 Series Service Guide THIS PAGE HAS BEEN INTENTIONALLY LEFT BLANK ...

Page 11: ...sight calibration services 18 Calibration interval 19 Adjustment is recommended 19 Recommended Test Equipment 20 Basic Operating Test 21 Backlight test U1271A U1272A only 21 Display test 21 Current terminal input test 22 Calibration Process 24 Test Considerations 25 Performance Verification Tests 26 Calibration Security 35 Unsecuring the Instrument for Calibration 36 To unsecure the instrument fro...

Page 12: ...djustment mode 46 Calibration Count 47 Calibration Error Codes 48 2 Service and Maintenance Troubleshooting 50 Checking the Fuse 51 Fuse Replacement 55 Returning the Instrument for Service 59 Replaceable Parts 60 To order replaceable parts 60 Types of Service Available 61 Extended service contracts 61 Obtaining Repair Service Worldwide 62 ...

Page 13: ...re 1 4 Input warning display µA mA terminal 23 Figure 1 5 Unsecuring the instrument 36 Figure 1 6 Changing the calibration security code 37 Figure 1 7 Resetting the calibration security code 38 Figure 1 8 Reference value display 45 Figure 2 1 Testing Fuse 1 53 Figure 2 2 Testing Fuse 2 54 Figure 2 3 Replacing Fuse 1 56 Figure 2 4 Replacing Fuse 2 57 Figure 2 5 Positions of Fuse 1 and Fuse 2 58 ...

Page 14: ...14 Keysight U1270 Series Service Guide THIS PAGE HAS BEEN INTENTIONALLY LEFT BLANK ...

Page 15: ...ist of Tables Table 1 1 Recommended test equipment 20 Table 1 2 Performance verification tests 27 Table 1 3 Adjustment input values 41 Table 1 4 Calibration error codes 48 Table 2 1 Operating checklist 50 Table 2 2 Fuse displayed readings 52 ...

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Page 17: ...Operating Test 21 Calibration Process 24 Test Considerations 25 Performance Verification Tests 26 Calibration Security 35 Unsecuring the Instrument for Calibration 36 Using the Front Panel for Adjustments 40 Calibration Count 47 Calibration Error Codes 48 This chapter helps you to verify the instrument performance and to make adjustments where necessary ...

Page 18: ...ation The instrument features closed case electronic calibration In other words no internal mechanical adjustments are required The instrument calculates correction factors based upon the input reference value you set The new correction factors are stored in the nonvolatile memory until the next calibration adjustment is performed The nonvolatile EEPROM calibration memory is retained even when the...

Page 19: ... are only guaranteed within the period stated from the last adjustment Keysight recommends that re adjustment should be performed during the calibration process for best performance This will ensure that the instrument will remain within the specifications for the next calibration interval This criterion for the re adjustment provides the best long term stability Performance data are measured duri...

Page 20: ...quipment Recommended accuracy requirements DC voltage Fluke 5520A 20 of the U1270 Series accuracy specification DC current Fluke 5520A 20 of the U1270 Series accuracy specification Resistance Fluke 5520A 20 of the U1270 Series accuracy specification AC voltage Fluke 5520A 20 of the U1270 Series accuracy specification AC current Fluke 5520A 20 of the U1270 Series accuracy specification Frequency Fl...

Page 21: ...Backlight test U1271A U1272A only Press and hold the key while turning the rotary switch to any other position OFF to ON Check that the multimeter s backlight is turned on Press any key to exit this mode Display test Press and hold the key while turning the rotary switch to any other position OFF to ON For U1273A U1273AX models Check that all the OLED pixels are lit Verify that there are no dead p...

Page 22: ...mode Figure 1 2 U1271A U1272A LCD screen Current terminal input test This test determines if the input warnings of the current terminals are functioning properly Input warning test A terminal The multimeter sounds a continuous alert beep when the test lead is inserted into the A terminal but the rotary switch is not set to the function The multimeter displays an input warning error Figure 1 3 Figu...

Page 23: ... mA terminal but the rotary switch is not set to the or function The multimeter displays an input warning error Figure 1 4 Figure 1 4 Input warning display µA mA terminal The alert beep tone will continue to beep until the test lead is removed from the µA mA terminal or until the rotary switch is set to the or function NOTE Before conducting this test ensure that the beep function is not disabled ...

Page 24: ...e the instrument for calibration see Calibration Security on page 35 4 Prior to performing the adjustments see the Adjustment considerations on page 40 5 Perform the adjustment procedure see Adjustment procedure on page 45 6 Secure the instrument against unauthorized calibration see Exiting the adjustment mode on page 46 Ensure that the instrument has quit the adjustment mode and is turned off 7 R...

Page 25: ...put under the laboratory environment for at least 1 hour Ensure that the calibration ambient temperature is stable and is between 18 C and 28 C Ideally the calibration should be performed at 23 C 1 C Ensure that the ambient relative humidity is less than 80 Allow a warm up period of 3 minutes Use a shielded twisted pair of PTFE insulated cables to reduce settling and noise errors Keep the input ca...

Page 26: ...ble for download at www keysight com find hhTechLib The performance verification tests are recommended as acceptance tests when you first receive the instrument The acceptance test results should be compared against the 1 year test limits After acceptance you should repeat the performance verification tests at every calibration interval If the instrument fails the performance verification tests ad...

Page 27: ... 20 V 1000 V 70 Hz 250 V ZLOW Turn the rotary switch to the position 1000 V 3 V 2 0 V NOTE First connect the COM and Ω terminals of the U1252B or equivalent to the COM and V terminals of the U1272A U1273A U1273AX then turn the U1272A U1273A U1273AX rotary switch to the position before proceeding with the following ZLOW functional test U1252B input ZLOW Turn the rotary switch to the position 1000 V...

Page 28: ...5 Hz 0 230 V 0 200 V 30 V 65 Hz 0 230 V 0 200 V 30 V 1 kHz 0 325 V 0 325 V 30 V 5 kHz 00625 V 0 475 V 30 V 20 kHz 0 640 V 0 640 V 27 V 100 kHz 0 985 V 300 V 300 V 45 Hz 2 30 V 2 00 V 300 V 65 Hz 2 30 V 2 00 V 300 V 1 kHz 3 25 V 3 25 V 300 V 5 kHz 6 25 V 4 75 V 270 V 20 kHz 5 80 V 1000 V 1000 V 45 Hz 9 0 V 8 0 V 1000 V 65 Hz 9 0 V 8 0 V 1000 V 1 kHz 12 5 V 12 5 V 1000 V 5 kHz 17 5 V Table 1 2 Perfo...

Page 29: ...e key twice 99 99 50 100 Hz 3 Vpp square wave 0 3 0 3 5 ACmV Turn the rotary switch to the position 30 mV 30 mV 20 Hz 0 235 mV 30 mV 45 Hz 0 200 mV 30 mV 65 Hz 0 200 mV 30 mV 1 kHz 0 235 mV 30 mV 5 kHz 0 325 mV 30 mV 20 kHz 0 340 mV 30 mV 100 kHz 1 090 mV 300 mV 300 mV 20 Hz 2 35 mV 300 mV 45 Hz 2 30 mV 2 00 mV 300 mV 65 Hz 2 30 mV 2 00 mV 300 mV 1 kHz 3 25 mV 2 35 mV 300 mV 5 kHz 6 25 mV 3 25 mV ...

Page 30: ...5 Hz 0 0235 V 3 V 65 Hz 0 0235 V 3 V 1 kHz 0 0360 V 3 V 5 kHz 0 0510 V 3 V 20 kHz 0 0675 V 2 7 V 100 kHz 0 1017 V 30 V 30 V 20 Hz 0 360 V 30 V 45 Hz 0 235 V 30 V 65 Hz 0 235 V 30 V 1 kHz 0 360 V 30 V 5 kHz 0 510 V 30 V 20 kHz 0 675 V 27 V 100 kHz 1 017 V 300 V 300 V 45 Hz 2 35 V 300 V 65 Hz 2 35 V 300 V 1 kHz 3 60 V 300 V 5 kHz 5 10 V 270 V 20 kHz 6 12 V Table 1 2 Performance verification tests co...

Page 31: ... before measuring the signal 9 AC DCmV Turn the rotary switch to the position and press the key twice 30 mV 30 mV 20 Hz 0 285 mV 30 mV 45 Hz 0 250 mV 30 mV 65 Hz 0 250 mV 30 mV 1 kHz 0 285 mV 30 mV 5 kHz 0 375 mV 30 mV 20 kHz 0 390 mV 30 mV 100 kHz 1 140 mV AC DCmV Turn the rotary switch to the position and press the key twice 300 mV 300 mV 20 Hz 2 70 mV 300 mV 45 Hz 2 35 mV 300 mV 65 Hz 2 35 mV 3...

Page 32: ...tle before pressing the key d The RH is specified for 60 e With a 2 wire connection and compensation enabled at calibrator 11 Diode Turn the rotary switch to the or position 3 V 3 V 0 0155 V 0 0155 V 12 Capacitance f Turn the rotary switch to the position 10 nF 10 nF 0 105 nF 0 105 nF 100 nF 100 nF 1 02 nF 1 02 nF 1000 nF 1000 nF 10 2 nF 10 2 nF 10 μF 10 μF 0 102 μF 0 102 μF 100 μF 100 μF 1 02 μF ...

Page 33: ...r 15 minutes before performing the measurement 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 ...

Page 34: ...mA 1 kHz 2 95 mA 2 95 mA 18 DCA h Turn the rotary switch to the position 3 A 3 A 0 0100 A 0 0100 A 10 A 10 A 0 04 A 0 04 A h CAUTION Connect the calibrator to the multimeter s A and COM terminals before applying the 3 A and 10 A input 19 ACA While the rotary switch is in the position press the key once 3 A 3 A 45 Hz 0 0325 A 0 0265 A 3 A 65 Hz 0 0325 A 0 0265 A 3 A 1 kHz 0 0325 A 0 0325 A 10 A 10 ...

Page 35: ...nsecure it by entering the correct security code see Unsecuring the Instrument for Calibration on page 36 The security code is set to 1234 when the instrument is shipped from the factory The security code is stored in nonvolatile memory and does not change when power has been turned off The security code may contain up to four numeric characters NOTE The security code can only be changed after the...

Page 36: ...ultaneously for more than 1 second The calibration security code entry is shown on the display Figure 1 5 Unsecuring the instrument 2 Key in the default security code if you are unsecuring your instrument for the first time Press or to move the cursor to the right or to the left Press or to increment or decrement the digit 3 Press when you are done NOTE If you forget your security code see To rese...

Page 37: ... 1 second 2 The factory default calibration security code 1234 is shown on the display if you are changing the calibration security code for the first time Figure 1 6 Changing the calibration security code 3 Set your new calibration security code Press or to move the cursor to the right or to the left Press or to increment or decrement the digit 4 Press to save the new calibration security code If...

Page 38: ... simultaneously for more than 1 second The calibration security code entry is shown on the display 3 Press for U1273A U1273AX or for U1271A U1272A for more than 1 second Figure 1 7 Resetting the calibration security code 4 Set the code to the same as the last four digits of the instrument s serial number Press or to move the cursor to the right or to the left Press or to increment or decrement the...

Page 39: ...ecurity code is now set to its factory default code 1234 If the incorrect security code is entered an error code will appear briefly after which the instrument will prompt you for the security code again If you want to enter a new security code see To change the calibration security code on page 37 Ensure that you record down the new security code ...

Page 40: ...ars replace the batteries as soon as possible to avoid false readings 3 Consider the thermal effects as you are connecting the test leads to the calibrator and multimeter It is recommended to wait for 1 minute before you begin the calibration after connecting the test leads 4 Before proceeding with the ambient temperature adjustment be sure to turn on the multimeter for at least 1 hour with the K ...

Page 41: ...e value 300 mV 300 00 mV 0 9 to 1 1 Reference value ACmV 30 mV 3 000 mV 70 Hz 0 9 to 1 1 Reference value 30 000 mV 70 Hz 0 9 to 1 1 Reference value 30 000 mV 30 kHz 0 9 to 1 1 Reference value 300 mV 30 00 mV 70 Hz 0 9 to 1 1 Reference value 300 00 mV 70 Hz 0 9 to 1 1 Reference value 300 00 mV 30 kHz 0 9 to 1 1 Reference value DCV SHORT SHORT SHORT V COM terminals 3 V 3 0000 V 0 9 to 1 1 Reference ...

Page 42: ... value 300 0 V 70 Hz 0 9 to 1 1 Reference value 300 0 V 3 kHz 0 9 to 1 1 Reference value DCμA OPEN OPEN OPEN terminals 300 μA 300 00 μA 0 9 to 1 1 Reference value 3000 μA 3000 0 μA 0 9 to 1 1 Reference value ACμA 300 μA 030 00 μA 70 Hz 0 9 to 1 1 Reference value 300 00 μA 70 Hz 0 9 to 1 1 Reference value 3000 μA 300 0 μA 70 Hz 0 9 to 1 1 Reference value 3000 0 μA 70 Hz 0 9 to 1 1 Reference value D...

Page 43: ...ance OPEN OPEN With cables connected to CAP COM terminals 10 nF 04 000 nF 0 9 to 1 1 Reference value 10 000 nF 0 9 to 1 1 Reference value 100 nF 010 00 nF 0 9 to 1 1 Reference value 100 00 nF 0 9 to 1 1 Reference value 1000 nF 0100 0 nF 0 9 to 1 1 Reference value 1000 0 nF 0 9 to 1 1 Reference value 10 μF 10 000 μF 0 9 to 1 1 Reference value 100 μF 100 00 μF 0 9 to 1 1 Reference value 1000 μF 1000...

Page 44: ... 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 vi...

Page 45: ... item will be shown on the display Figure 1 8 Reference value display 4 Configure each calibration item 5 Use the arrow keys to select the calibration range 6 Apply the input signal shown in the Reference value column of Table 1 3 The analog bar graph displays the input reading There is no bar graph display for temperature adjustment NOTE Review the Test Considerations and Adjustment consideration...

Page 46: ...umn shown in Table 1 3 Repeat step 3 to step 8 for each adjustment point shown in the adjustment table 11 Verify the adjustments using the Performance Verification Tests on page 26 Exiting the adjustment mode 1 Remove all the shorting plugs and connectors from the instrument 2 Record the new Calibration Count 3 Press and simultaneously to exit the Adjustment Mode 4 Cycle the instrument s power The...

Page 47: ...set to 0 The calibration count can be read from the front panel after the instrument has been unsecured 1 In adjustment mode press to view the calibration count 2 Take note of the calibration count to keep track of the number of calibrations that have been performed 3 Press again to exit the calibration count mode NOTE The instrument has been calibrated before it left the factory You are recommend...

Page 48: ... Table 1 4 Calibration error codes Code Descriptions Er002 Calibration error secure code invalid Er003 Calibration error serial number code invalid Er004 Calibration error calibration aborted Er005 Calibration error value out of range Er006 Calibration error signal measurement out of range Er007 Calibration error frequency out of range Er008 EEPROM write failure ...

Page 49: ...Checking the Fuse 51 Fuse Replacement 55 Returning the Instrument for Service 59 Replaceable Parts 60 Types of Service Available 61 Obtaining Repair Service Worldwide 62 This chapter will help you troubleshoot a failing instrument It also describes how to obtain repair services and lists the replaceable assemblies ...

Page 50: ... is not covered in this manual should only be performed by qualified personnel Table 2 1 Operating checklist Malfunction Identification No display when powered ON using the rotary switch Verify the batteries health and replace batteries as necessary No beeper tone Verify that the beeper is enabled in the multimeter s setup mode Failed on current measurement Verify the fuses health and replace the ...

Page 51: ...rminal Ensure that the probe tip touches the metal inside the µA mA input terminal as shown in Figure 2 1 3 To test Fuse 2 place and touch the tip of the test probe on the left half of the A input terminal Ensure that the probe tip touches the metal inside the A input terminal as shown in Figure 2 2 4 Observe the reading on the instrument s display Refer to Table 2 2 below for the possible reading...

Page 52: ...ysight U1270 Series Service Guide Table 2 2 Fuse displayed readings Current input terminal Fuse Part number Fuse rating Displayed readings Fuse healthy Replace fuse 1 2110 1400 440 mA 1000 V 102 Ω OL 2 2110 1402 11 A 1000 V 0 05 Ω OL ...

Page 53: ...Service and Maintenance 2 Keysight U1270 Series Service Guide 53 Figure 2 1 Testing Fuse 1 Smart Smart ...

Page 54: ...2 Service and Maintenance 54 Keysight U1270 Series Service Guide Figure 2 2 Testing Fuse 2 Smart Smart ...

Page 55: ...ve the battery cover 2 Locate the faulty fuse Fuse 1 see Figure 2 3 is located to the right of batteries and Fuse 2 see Figure 2 4 is located at the bottom of the batteries See Figure 2 5 for the specific location size and ratings of Fuse 1 and 2 Gently remove the defective fuse by prying one end of the fuse with a flathead screwdriver and removing it out of the fuse bracket Replace a new fuse of ...

Page 56: ...2 Service and Maintenance 56 Keysight U1270 Series Service Guide Figure 2 3 Replacing Fuse 1 1 2 3 ...

Page 57: ...Service and Maintenance 2 Keysight U1270 Series Service Guide 57 Figure 2 4 Replacing Fuse 2 1 2 3 ...

Page 58: ...2 Service and Maintenance 58 Keysight U1270 Series Service Guide Figure 2 5 Positions of Fuse 1 and Fuse 2 Fuse 1 10 35 mm 440 mA 1000 V fast acting fuse Fuse 2 10 38 mm 11 A 1000 V fast acting fuse ...

Page 59: ...ument 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 Place the instrument in its original container with appropriate packaging material for shipping If the original shipping container is not available place your unit in a c...

Page 60: ...ude a brief description of each part with its corresponding Keysight part number To order replaceable parts You can order replaceable parts from Keysight using the Keysight part number Note that not all parts listed are available as field replaceable parts To order replaceable parts from Keysight do the following 1 Contact your nearest Keysight Sales Office or Service Center 2 Identify the parts b...

Page 61: ...rranty After your warranty expires Keysight offers repair services at competitive prices Extended service contracts Many Keysight products are available with optional service contracts that extend the covered period after the standard warranty expires If you have such a service contract and your instrument fails during the covered period Keysight will repair or replace it in accordance with the co...

Page 62: ...btain warranty service or technical support information you can contact Keysight at one of the following telephone numbers In the United States 800 829 4444 In Europe 31 20 547 2111 In Japan 0120 421 345 Or use our Web link for information on contacting Keysight worldwide www keysight com find assist Or contact your Keysight representative Before shipping your instrument request the Keysight Servi...

Page 63: ...on is subject to change without notice Always refer to the Keysight website for the latest revision Keysight Technologies 2010 2016 Edition 17 July 30 2016 Printed in Malaysia U1271 90020 U1271 90020 www keysight com ...

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