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IR4051 IR4052 IR4053 Instruction Manual INSULATION TESTER Video Scan this code to watch the instructional video(s). Carrier charges may apply. Read carefully before use. Keep for future reference. Sept. 2023 Revised edition 9 [600387699] IR4051A981-09 HIOKI IR4051A981-09...
Inspecting the Instrument When Using the L9788-10 Test Lead with Remote Switch (Red) ..............23 Configuring the Comparator ...... 24 2.4.1 Setting the Comparator ....25 2.4.2 Canceling the Comparator ..... 25 Insulation Resistance Measurement ..........27 IR4051A981-09 HIOKI IR4051A981-09...
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2.10 Auto power save (power-saving function) . 50 2.11 Auto-backlight-off ........50 Chapter 3 Specifications Chapter 4 Maintenance and Service Troubleshooting ........63 Replacing Batteries or Fuse...... 68 Replacing the Pin (Option) ......71 Cleaning ............ 72 Appendix HIOKI IR4051A981-09...
Introduction Introduction Thank you for purchasing the HIOKI Model IR4051, IR4052, IR4053 Insulation Tester. To obtain maximum performance from the instrument, please read this manual first, and keep it handy for future reference. The “instrument” in this manual means IR4051, IR4052, or IR4053.
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Neck strap (Included with the IR4051 and IR4053.) ×1 LR6 Alkaline battery ×4 * L9787 Test Lead and L9788-11 Test Lead Set with Remote Switch are all exclusively designed for the HIOKI IR4000 series. Do not use for any other purpose. HIOKI IR4051A981-09...
Carrying case for the IR4052 L9787 Test Lead, L9788-10 Test Lead with Remote Switch (Red) and L9788-11 Test Lead Set with Remote Switch are all exclusively designed for the HIOKI IR4000 series. Do not use for any other purpose. HIOKI IR4051A981-09...
• Protective gear This instrument is measured on a live line. To avoid electric shock when measuring live lines, wear appro- priate protective gear, such as insulated rubber gloves, boots and a safety helmet. HIOKI IR4051A981-09...
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Indicates that incorrect operation presents a possibility of injury to the user or damage to the instrument. Indicates advisory items related to performance or correct operation of the instrument. HIOKI IR4051A981-09...
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Indicates a prohibited action. (p. ) Indicates the location of reference information. Indicates that descriptive information is provided below. Indicates a function of the IR4051 Insulation Tester. IR4051 Indicates a function of the IR4052 Insulation Tester. IR4052 Indicates a function of the IR4053 Insulation Tester.
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Use of a measurement instrument that is not CAT-rated in CAT II to CAT IV measurement applications could result in a severe accident, and must be carefully avoided. HIOKI IR4051A981-09...
If you find any damage, contact your authorized Hioki distributor or reseller. To prevent an electric shock accident, confirm that the white or red portion (insulation layer) inside the cable is not exposed.
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Connections should never be made to the primary side of a breaker, because unrestricted current flow could cause a serious accident if a short circuit occurs. HIOKI IR4051A981-09...
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Furthermore, if the 9804-02 is brought near precision electronic equipment such as comput- ers, TV screens, or electronic wrist watches, they may fail. • To avoid electric shock, do not exceed the lower of the ratings shown on the instrument and test leads. HIOKI IR4051A981-09...
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0: The equipment inside the enclosure is not protected against the harmful effects of water. 索引 The battery indicator flashes when the remaining battery capacity is low. In this case, measurement is not possible. Replace the batteries. (p.68) HIOKI IR4051A981-09...
Low variation in measured values The instrument generates little variation in measured values when used in a typical measuring environment. 索引 Easy-to-view display The instrument uses an LCD with a wide viewing angle and a backlight driven by a high-brightness white LED. HIOKI IR4051A981-09...
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IR4052 User-selectable number of display digits The instrument’s number of display digits can be changed. IR4053 Ω measurement function The PV measurement allows accurate insulation resis- Ω tance measurements of a solar panel. HIOKI IR4051A981-09...
1.3 Names and Functions of Parts 1.3 Names and Functions of Parts Front Panel Terminals (on top) Terminals for con- IR4051 IR4052 trolling Model L9788- *This figure is model “2. Measurement Display (p.23) (p.23) Procedures” EARTH terminal LINE terminal Measure key...
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Turns on when the comparator judgment is PASS (good). See: “2.4.1 Setting the Comparator” (p.25) Turns on when the comparator judgment is FAIL (defective). See: “2.4.1 Setting the Comparator” (p.25) Flashes when a dangerous voltage exists between the measurement terminals. HIOKI IR4051A981-09...
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Turns on when the instrument is set to the 500 V range or the 1000 V range. Pressing turns off the indicator and enables insulation measurement. Display IR4051 Measured value or Comparator reference value Lights up when the criterion for the comparator 索引...
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500 V or 1000 V ranges is used (to prevent from misuse). Other functions are same with the • When PVΩ range is set, the ones for IR4051 and IR4052. voltage to be applied will be determined. Display IR4053...
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Tester, take note that a test voltage will be discharged even when the MEASURE key of the Tester is pressed. L9788-92 Breaker Pin Connection First take out the sleeve from the L9788-10, and then install the Breaker pin (L9788-92). 索引 Plug it all the way to the end. HIOKI IR4051A981-09...
(p.7) in the instruction manual. • When performing measurements with the sleeves attached, be careful to avoid damaging the sleeves. If the sleeves are inadvertently removed during measurement, be especially careful in handling the test leads to avoid electric shock. HIOKI IR4051A981-09...
Attaching the strap Slightly extend each of the four dou- ble-loop split rings and pass the ring IR4051 IR4053 through a lug-hole on the instrument. Pass the ring on both ends of the supplied strap through each of the four holes in the instrument.
Contact your No Exposed authorized Hioki distributor or reseller for replacements. 1. Use the rotary selector to The following select Insulation Resis- issues may be tance.
L9788-10’s MEASURE key turns red when the instrument’s live wire warning is displayed and that the display shows 0 MΩ. 索引 Press of the instrument to confirm that the light at the tip of the L9788-10 comes on. HIOKI IR4051A981-09...
PASS judgment. The buzzer will sound in the event of a PASS result. Comparator settings for each range will be saved, even if the instrument is turned off. The comparator cannot be used with voltage ranges. HIOKI IR4051A981-09...
” to flash and displays the resistance value that will be used as the judgment reference. IR4051 IR4053 The IR4051 will display “ .” Press to select the judgment reference. If you do nothing for about 2 seconds after you select the desired judgment reference, the comparator will be set, and the “...
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0.05 50 V 125 V 250 V MΩ 500 V/ PVΩ500V 1000 V PVΩ1000V Ω Ω *1: Factory initial setting *2: Factory initial setting when PVΩ function is selected. *3: Reference 0.1 to 0.5 is only for IR4053. HIOKI IR4051A981-09...
• When inspecting on an electric power circuit including an appliance whose withstand voltage is lower than the test voltage or including an appliance or components whose withstand voltage is unknown, it is recommendable to remove that from the circuit for measurement. HIOKI IR4051A981-09...
500 V, 1000 V, or PV range. Releasing the lock Ω Setting the rotary selector to the 500 V, 1000 V, or PV range will cause (IR4052) or (IR4051, IR4053) to light up, and will flash. Flashing HIOKI IR4051A981-09...
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, disabling the lock. The display will also change to the measurement screen. The instrument will return to the state described in Step when 1 minute elapses after the last measurement or operation. Press to release the lock. 索引 HIOKI IR4051A981-09...
Connect the red test lead to the line to be measured. Pless and hold the MEASURE key. (To make continuous measurements, pull the button up.) Read the value after the indicator has stabilized. Turn off the MEASURE key while the test leads are connected to the measurement object. HIOKI IR4051A981-09...
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• During measuring, do not selector over to the other function. • The instrument will return to the locked state when about 1 minute of no operation elapses in the 500 V and 1000 V ranges. To continue measurement, press again to release the lock. 索引 HIOKI IR4051A981-09...
1,000 count Ω display mode would be shown as 57 M in 100 count mode or Ω 50 M in 10 count mode. Display mode Number of Example display digits display display 1,000 count 100 count 10 count HIOKI IR4051A981-09...
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10 count display mode 100 count display mode 50 V 100 MΩ 10 MΩ 125 V 250 MΩ 20 MΩ 250 V 500 MΩ 50 MΩ 500 V 2000 MΩ 100 MΩ 1000 V 4000 MΩ 2000 MΩ 索引 HIOKI IR4051A981-09...
Regardless of the selected display mode, 1-min. values are always displayed in 1,000 count display mode. 1-min. value Use this function when measuring targets that include a capacitance component. This function is enabled only when the comparator is set to “off.” HIOKI IR4051A981-09...
2.5 Insulation Resistance Measurement 2.5.5 Voltage Characteristic of Measuring Terminals Rating 1000 V Rating 500 V Rating 250 V Rating 125 V Rating 50 V Resistor to be measured [MΩ] 索引 HIOKI IR4051A981-09...
The discharge will end when the disappears. (The time required for discharge depends on the capacitance value.) Measurement of a solar panel may fail to turn off because the voltage generated by the solar panel is detected after completely discharged. HIOKI IR4051A981-09...
• To avoid electrical shock, be careful to avoid shorting live lines with the test leads. Never press the MEASURE key while measuring 索引 voltage. Doing so could damage the circuitry or cause an accident that might result in injury or death. HIOKI IR4051A981-09...
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Connect the red test lead to the line side of the breaker. Read the value after the indicator has stabilized. • During measuring, do not selector over to the other function. • For waveforms other than sine waves, some errors may occur. HIOKI IR4051A981-09...
When measured voltage is -1 V or lower, the dis- play lights in red and white alternately. OFF: Disables this function. When no operation is made until approximately two seconds after ON or OFF is selected, the setting chosen will be fixed and measurement screen appears. 索引 HIOKI IR4051A981-09...
2.8 Low Resistance Measurement 2.8 Low Resistance Measurement IR4051 IR4052 Do not measure under a live circuit condition. Before measurement, always perform zero adjustment to cancel the test leads’ wiring resistance and other potentially problematic quantities. Accurate measurement will not be possible if zero adjustment is not performed.
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Ex. Checking the continuity of ground wiring 索引 If an additional operating circuit is connected in parallel to the circuit under measurement, the measurement error may occur due to the effects of impedance of the circuit connected in paral- lel or transient currents. HIOKI IR4051A981-09...
Do not short-circuit two wires to be measured by bringing the metal part of the test lead into contact with them. It may cause a major accident such as arc. HIOKI IR4051A981-09...
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• Maximum rated voltage between terminals of the 索引 IR4053 is 1000 V DC/600 V AC. Do not use this instrument for facilities using a voltage over 1000 V DC or 600 V AC. Doing so may cause an electrical shock or a failure. HIOKI IR4051A981-09...
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• Measurements with P-N shorted should use an insulation resistance range other than PV range. Ω • Do not make any measurement if any of the bypass diodes of the solar panel has failed. Doing so may damage the solar panel. HIOKI IR4051A981-09...
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10MΩ resistor is used, the output voltage is divided by 1 MΩ and 10 MΩ. • During hours such as in the nighttime while a solar panel is not generating power, make measurements with P-N shorted. 索引 HIOKI IR4051A981-09...
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String Main switch Disconnect switch Power conditioner Arrestor Connec- tion box The figure shows an example of solar power generator. The configuration may be different from actual generator. HIOKI IR4051A981-09...
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Note: If a voltage is being generated between terminal P and ground, there may be deteriorated insulation performance. If the object to be measured has a voltage, voltage detection make the display light in red and white alternately. 索引 HIOKI IR4051A981-09...
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N of the procedure 10. Doing so may damage the solar panel. Check the insulation resistance reference in advance with safety standards. HIOKI IR4051A981-09...
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Turn ON all disconnect switches used for strings. Return main switch of the connection box to ON. After one minute is elapsed from the last measurement or last operation, lights and 500V/ 1000V RELEASE key blinks. Press the key to release the lock. 索引 HIOKI IR4051A981-09...
Disabling the auto-backlight-off function While the backlight is off, press and hold for about 2 minutes until a continuous beep-beep-beep sound is heard. Repeat this procedure after turning the instrument off. HIOKI IR4051A981-09...
Insulation resistance measurement test. Power automatically turns OFF approximately 10 minutes after the last operation or hot-line warning indication. Auto Power Save Can be displayed using the power supply activation options. 索引 HIOKI IR4051A981-09...
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Guaranteed 1 year accuracy period Product warranty 3 years period Model IR4051 and IR4052 -25°C to 40°C (-13.0°F to 104.0°F) 90% RH or lower (non-condensing) Operating 40°C to 65°C (104.0°F to 149.0°F), at 65°C and temperature and below relative with linear decrease up to 25% RH...
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IR4051, IR4053: Approx. 159W×177H×53D mm Dimensions (6.26”W×6.97”D×2.09”D) (excluding protru- IR4052: Approx. 152W×92H×40D mm sions) (5.98”W×3.62”D×1.57”D) IR4051, IR4053: Approx. 600g (21.2 oz.) Mass IR4052: Approx. 440g (15.5 oz.) (including battery, excluding test lead) Accessories Refer to “Verifying Package Contents” (p.1). Options Refer to “Options”...
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±4%rdg. tolerance) 2nd effective 10.1 to 25.1 to 50.1 to 501 to 1010 to measuring 100.0 2000 4000 range [MΩ] Accuracy (Limit deviation ±8%rdg. tolerance) Other measur- 0 to 0.199 ing range [MΩ] Accuracy (Limit deviation ±2%rdg.±6dgt. tolerance) HIOKI IR4051A981-09...
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-25°C to 0°C, (less than -25°C to (less than -25°C to perature (E 50°C to 65°C) 0°C, 50°C to 65°C) 0°C, 50°C to 65°C) (Model IR4051 (Model IR4051 (Model IR4051 and IR4052 only) and IR4052 only) and IR4052 only) ±4%rdg. and ±8%rdg.
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600 V AC (10 s), 1200 V DC (10s) for IR4053 only Display IR4052: Within 0.6 s (no update during response) update IR4051, IR4053: Within 1.0 s (no update during response) interval Measurement terminal voltage characteristic Open-circuit 1 to 1.2 times of rated measurement voltage...
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100.0 Ω 0.1 Ω ±3%rdg.±2dgt. 1000 Ω 1000 Ω 1 Ω *1: Displayed value before zero adjustment *2: Accuracy is applicable for displayed values after zero adjustment (when the temperature changes more than 1°C, zero adjustment is necessary) HIOKI IR4051A981-09...
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0.01 V 420 V 420.0 V 0.1 V ±1.3%rdg.±4dgt (Accuracy of range IR4051: over 600 V* is not 600 V IR4051: 750 V guaranteed) IR4052: IR4052: 750 V 600 V IR4053: 1100 V IR4053: 索引 1000 V *For only IR4053, the accuracy is guaranteed up to 1000 V.
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Open-circuit voltage* 1 to 1.2 times of measurement voltage Lower limit resistance value to be maintained rated 20 MΩ ±5% 20 MΩ ±5% measurement voltage Rated current 0.025 mA ±20% 0.05 mA ±20% Short-circuit current 1.2 mA or less HIOKI IR4051A981-09...
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For example for an open voltage measurement using a DMM with its input imped- Ω Ω Ω ance at 10 M , the output voltage is divided by the 1 M and 10 M 索引 HIOKI IR4051A981-09...
• When sending the instrument for repair, remove the batteries and pack carefully to prevent damage in transit. Include cushioning material so the instrument cannot move within the package. Be sure to include details of the problem. Hioki cannot be responsible for damage that occurs during shipment.
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The test leads are not securely connected. the maximum → Check the connection between the test leads display value. and the instrument, and check the connection of the tips of the test leads. HIOKI IR4051A981-09...
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The measurement target has a large capacitance made easier to component (capacitor). read by reducing → If it is possible to remove the capacitor, do so. If the number of not, use the lowest measured value as the display digits.) measurement result. 索引 HIOKI IR4051A981-09...
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* Polarization: A phenomenon whereby a substance’s positive and negative electric charges move in opposite directions when an electric field is applied to it, causing the center position of the positive and negative charges to shift. HIOKI IR4051A981-09...
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Repair is required. has been corrupted. The measurement circuit is Repair is required. broken. The voltage generation Repair is required. circuit is broken. There is a broken Replace the indicated connection in the fuse. protective fuse. See: p.68 索引 HIOKI IR4051A981-09...
Fuse type: FF0.5AH/1000V (70 172 40.0.500: SIBA) (Very fast acting, arc extinction type, high rupturing capacity type) Fuses can be purchased from your Hioki distributor. • To avoid electric shock, turn off the rotary selector and disconnect the test leads from the object to be measured, before replacing the batteries or fuse.
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• Continuous operating time when LR6 Alkaline batteries are used (reference values at 23°C) Approx. 20 hours (without the Z3210 installed, with the com- parator and backlight set to off, when making measurement using the 500 V range with the measurement terminals open- HIOKI IR4051A981-09...
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500 V range with the measurement terminals open-circuited) Visit an FAQ page on Hioki’s global website for more information about nickel-metal hydride batteries that Hioki has guaranteed to work.
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4.2 Replacing Batteries or Fuse Loosen the central fastening screw at the back of the instrument and remove the battery cover. Replace all four batteries or the fuse. Slide the battery cover back into place and tighten the screw. 索引 HIOKI IR4051A981-09...
The pin at the front of the Model L9788-10 (option) can be replaced when it has worn away or is damaged. Replacement pins are available at your authorized Hioki distributor or reseller. (Model L9788-90 Tip Pin) Turn off the power of the instrument and disconnect the L9788-10.
• Wipe the LCD gently with a soft, dry cloth. • As dirt accumulated on the metal part of alligator clip has an effect on measurements, keep the surfaces clean by gently wiping with a soft cloth. 索引 HIOKI IR4051A981-09...
I that flows to the target as a result, and dividing the voltage V by the leak current I. 2. Low resistance measurement IR4051 IR4052 The measurement target’s resistance Rx is calculated by applying a current I to the measurement target, measuring...
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4.5 V to 6.8 V ±4%rdg. ±3%rdg.±2dgt. voltage Temperature 0°C to 35°C ±4%rdg. ±3%rdg.±2dgt. Operation ±12%rdg. ±30%rdg. uncertainty 1st effective Guaranteed range of operation 0.2 Ω to 2 Ω measurement uncertainty range Influencing factor non-applicable for E and E to E HIOKI IR4051A981-09...
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This measurement allows accurate measurements but is also a highly dangerous method as arc discharge may be generated due to the short circuit. There is also a fire risk depending on the deterioration level of the solar panel. 索引 Connection box Earth HIOKI IR4051A981-09...
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Insulation Resistance Measurements for Solar Cell Array HIOKI IR4051A981-09...
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