What are the precautions when using a DC resistance tester?

Wiring method. The current circuit should be connected with the thick wire in the test line, and the voltage circuit should be connected with the thin wire in the test line. (This instrument is equipped with a set of 4 8m test line).

1. The measurement wiring of a single resistance is shown in the figure below, and Rx is the measured resistance.

2. When the measurement resistance is greater than"2ω", you can select the constant current for the test, press"Move"keys will indicate arrows"↑"Move right, select"a", press the Confirm button, and then press"Print"key to increase, press"Move"key reduction. You can use this formula i=10 to roughly estimate the current, select the appropriate current to improve the measurement accuracy, press the confirm button to display the loop current, and then press the confirm button to test. After the resistance value is displayed, it can be printed and discharged.

How it works: The DC resistance tester is equipped with:"Reset"、"Print"、"Move"、"Discharge"、"OK"Five buttons.

1. Resistance measurement:

After the instrument is powered on or the reset button is pressed, it enters the initial state (1). Press"Move"key to make"↑"The cursor pointer arrow moves back and forth to select the desired function to make"↑"key pointing"ω"Press"OK"button to enter the automatic measurement resistance state (2) and display the resistance value (3). Press once"Print"key to print the measurement results.

When the test is complete, press"Discharge"button, and the instrument will automatically discharge.

Precautions. 1. When using the instrument, do not block the exhaust fan window to facilitate heat dissipation.

1. Precautions:

1. The DC resistance tester can be used indoors and outdoors, but it should not be used in places such as direct sunlight, rain, corrosive gases and excessive dust;

HM-10A DC Resistance Tester.

2. Before use, the grounding end of the instrument must be well grounded;

3. In case of sudden power failure during the test, please do not unplug the test line immediately, and then unplug the instrument after discharge;

4. During the test, it is forbidden to move the test clip and power cord.

5. Measure the no-load voltage regulating transformer. When the tap test is complete, press the cancel or reset key to discharge the system. After the discharge indication stops, switch gears for the next measurement.

6. Complete the measurement of on-load voltage regulating transformer at one time. The instrument programming allows the tap-changer to be connected to the next tap after one tap test is completed, and the instrument will move on to the next tap measurement.

7. After the test, turn off the power first, and then remove the test line;

2. Common fault solutions.

Fault 1: No display at startup.

1) The fuse tube of the power outlet is damaged.

2) The internal plug-in of the instrument is loose.

3) Computer board failure.

Fault 2: "Out of range or line not connected" is displayed

1) Instrument power failure.

2) A D board failure.

3) The test line is in poor contact or does not form a loop.

1.After the instrument is tested by the DC power supply, the battery in the machine should be charged and maintained in time.

2. During the DC test, if the under-voltage indicator light is on, stop using the DC power supply and use the AC power supply instead.

3. When the instrument is not used for a long time, the battery pack in the instrument should be charged and maintained regularly, generally for about 14 hours, until the "full" indicator light is on.

4. This instrument should be protected from moisture, dropping, exposure to the sun, etc.

The DC resistance tester takes the high-speed microcomputer processor as the core, adopts the high-speed AD converter and the program-controlled current source Jichang type technology, which realizes fast measurement results and highly automated measurement functions. It has the characteristics of high accuracy, wide measurement range, stable data and good repeatability. Strong anti-interference ability, perfect protection of Gongshan Xun, fast charging and discharging speed.

The DC resistance tester is small in size, light in weight and easy to carry. It is an indispensable product for DC resistance testing of inductive loads.

HM-20A DC Resistance Tester.

The DC resistance tester has complete protection functions, which can reliably protect the impact of back electromotive force on the instrument, and has the function of automatic discharge indication. The measured current and measurement time can be displayed. Intelligent power management technology can effectively reduce the heat generated inside the instrument.

Up to 120 measurements can be stored. The full Chinese menu and operation tips are intuitive and convenient.

Explain the fault and troubleshooting method of DC resistance tester

1. There is no display when you turn on the machine, the reason is that there is no AC 220V, and the solution is to check the power cord and insurance.

2. The abnormal display is because the motherboard or monitor is faulty. The solution is to check your computer's motherboard or replace your monitor.

3. Fuse fuse when charging. The main cause is the failure of the current source. The solution is to replace the constant current switching power supply.

4. Display failure 1, the main reason is the hardware circuit failure, the solution is to check the computer motherboard.

5. Display fault 2, the main reason is that the current loop is not connected or the current source is faulty. The solution is to check the wiring.

6. Display failure 3, the main reason is that the charging current does not meet the requirements, and the treatment method is that the contact resistance is too large.

7. Display failure 4. The main reason is that the tested product is out of the measurement range.

DC Resistance Tester Product Features:

1. Fast measurement speed: the instrument outputs a constant 10A high current, which can effectively compensate the current inertia of the large inductance device during measurement, accelerate the saturation of the magnetic core, thereby shortening the charging time and improving the measurement speed. The bridge is hundreds of times faster.

2. High precision: This resistance tester adopts advanced single-chip microcomputer high-power and high-precision program-controlled constant voltage and constant current technology, so that the charging current of the inductive load is kept at a relatively stable value, and the stability is strong in anti-inductance and anti-interference. to ensure measurement accuracy.

3. The instrument has a high degree of intelligence, compact structure, and novel and reasonable layout. In addition to the advanced four-terminal measurement method, it also adopts dual-channel control comparative analysis, automatic zeroing, and is equipped with arc prevention and data analysis circuits. Automatic output of printed measurement data, menu operation, man-machine dialogue, convenient operation reading.

In the process of measurement, in addition to strictly abiding by the electrical safety regulations and equipment test procedures, special attention must be paid to the measurement under the condition of stable temperature of the first circle, and the temperature difference between the upper and lower temperature transformer fuel tank does not exceed 3. Due to the inductance of the transformer coil, the charging current is unstable during measurement. Be sure to wait until the current is stable before counting.

If necessary, take steps to shorten the charging time. Minimize the contact resistance of the wires in the test circuit. Transformer taps in operation are often affected by dirt such as oil film and have poor contact.

Generally, it is necessary to switch after a few times to avoid misjudgment.

DC resistance testers often have the following faults: the pointer of the ground resistance tester does not move, or the pointer of the battery voltage and ground resistance tester does not move during measurement.

Cause of failure: It may be caused by a burned head or wiring that connects the plug to the circuit board. This is also caused by excessive vibration of the ground resistance tester during use or transportation.

Method steps: First, open the header board, manually move the pointer and other pointers, the pointer cannot be automatically zeroed, indicating that the header is damaged; Otherwise, the header is soldered, the meter head is measured with a multimeter resistor, and if the meter is open, the header burns out. Then measure the original connection of the meter head with the multimeter current and voltmeter, press the check voltage button of the ground resistance meter.

If the multimeter has a voltage indication, it means that only the fault of the ground resistance tester is caused by a damaged meter head, which can be repaired after replacing the meter head with a new one. If the meter is in good condition, open the ground resistance tester housing. Check the header connection if it is disconnected.

The testing of transformer DC resistance tester is the key work of whether power equipment can be integrated into the operation of the power grid. It is one of the effective means to ensure the safe operation of the power system. China's electric power industry standard stipulates the corresponding test items and test standards for the state test of the 10kV hollow reactor handover test hall.

The measurement of DC resistance is an important part of the transfer test, so it is particularly important to correctly diagnose the results of DC resistance measurements. The 10kV shunt capacitor device is usually composed of capacitors, series reactors, discharge coils, fuses and other components, and the series reactors can be divided into hollow type and iron core type according to the presence or absence of iron cores in the windings, and the purpose of series reactors is mainly to limit harmonics and effectively suppress the inrush current generated when the capacitor device is put into the power grid. In addition, it plays a very important role in preventing and reducing reignition caused by capacitor switching.

The hollow reactor generally adopts a concrete pouring structure, which is generally a single-phase structure, and the current 10

The KV shunt capacitor device adopts the combination of three-phase vertical overlap, which requires a small number of turns of the B-phase winding and the opposite winding direction. The 110kV substation 10kV shunt capacitor devices are all installed in the capacitor room, and there are two groups or three groups of capacitor devices in the room.

It is very important for the transformer DC resistance tester to use ordinary DC bus. In the process of power-up, the control of the inverter, the transmission fault, the load characteristics and the maintenance of the input main circuit must be fully considered, and the scheme includes a three-phase line, a DC bus, a universal inverter, a common braking unit or an energy feedback device and some accessories.

The transformer DC resistance tester is based on a high-speed microprocessor and uses high-speed AD converter and programmable current source technology to achieve fast measurement results and highly automated measurement functions. It has the advantages of high precision, wide measurement range, stable data and good repeatability. It is an indispensable product for DC resistance testing of inductive loads.

Troubleshooting and troubleshooting methods of DC resistance tester:

1.There is no display at startup, the reason is not AC 220V, the solution is to check the power cord and fuse.

2.If the display is abnormal due to a malfunction of the motherboard or monitor, the solution is to check the motherboard of the computer or replace the monitor.

3.Insurance is required when charging. The main cause is the failure of the current source. The solution is to replace the constant current switching power supply.

4.Fault 1 is displayed. The main reason is a hardware circuit failure. The solution is to check the motherboard of your computer.

5.Fault 2 is displayed. The main cause is that the current loop is not connected or the current source is faulty. The solution is to check the wiring with a clear solution.

6.Fault 3 is shown. The main reason is that the charging current does not meet the requirements. And the contact resistance of the treatment method is too large.

In the measurement process of the DC resistance tester, in addition to strictly complying with the electrical safety regulations and equipment test procedures, special attention must also be paid to the measurement under the condition that the temperature of the ** ring is stable and the difference between the upper and lower limits. The temperature of the transformer tank does not exceed 3. Due to the inductance of the transformer coil, the charging current during the measurement is unstable.

Make sure to count only after the current is stable. If necessary, take steps to shorten the charging time. Try to reduce the contact resistance of the wires in the test circuit.

Transformer taps in operation are often affected by dirt (e.g. oil film), resulting in poor contact. Often, it is necessary to switch more than one time to avoid misjudgment.

Respondent: Huatian Power.

A: DC power supply test:

Close the main power switch, there is an indicator light on accordingly, press the "start and stop" button, and the test can be carried out. After the test is completed, press the "reset button", the instrument displays "discharging", wait for the instrument to return to the interface of the boot, turn off the main power switch, the corresponding indicator light is off, and then convert the test clip to test again.

b. AC power test:

Connect the AC AC220V power supply, the "charging" indicator light is on, close the main power switch, the corresponding indicator light is on, press the "start and stop" button, and the test can be carried out. After the test is completed, press the "reset button", the instrument displays "discharging", wait for the instrument to return to the interface of the boot, turn off the main power switch, the corresponding indicator light is off, and then convert the test clip to test again.

Note: After the test is completed, you must press the "reset button" and other instruments to return to the boot interface before you can shut down for the next test.

Huatian Power HTZZ-2A DC Resistance Rapid Tester.

Operational content.

1. Preparation.

The protective end of the three-wire power socket should be connected to the ground wire and should not be suspended, otherwise the chassis will lose its shielding effect and will run. Turn on the power and press the "Power" button.

2. Clearing.

Short the two measuring clips and then clear them.

3. Function Selection.

According to the need, the speed is adjusted, parameters, display form, continuous or single test settings, etc.

4. Resistance measurement.

According to the size of the resistance to be measured and the number of bits to be displayed, select the appropriate range and number of digits to be displayed. Connect the test clamp to the measured resistance, and the clamp should be clamped close to the measured part and read out the resistance value.

5. When measuring continuously, there is no need to re-zero.

When the measurement is not performed, disconnect the power supply in time.