Testing Tips

How to Correctly Measure the Insulation Resistance of Power Transformer?

1. Check the safety measures before the test, and the power supply and all external connections of the tested product should be removed. The tested product is grounded and discharged, and the large-capacity equipment is discharged for at least 5min. Do not touch the discharge wire directly with your hands.

2. According to the dirty and wet surface conditions, decide whether to take surface shielding or need to dry and wipe the surface dirt to eliminate the influence of surface dirt on insulation resistance.

3. Stabilize the insulation resistance tester and check whether the insulation resistance tester refers to "0" or "∞". When shorting "L" and "E", it should be instantaneous and low speed to avoid damage to the insulation resistance tester.

4. The measurement part of the test product is connected between the "L" and "E" terminals, and the "L" terminal is connected to the high-voltage measurement part. The "E" terminal is connected to the low voltage or housing ground section. The driving (shaking) insulation resistance tester reaches the rated speed (120r/min) and reads the insulation resistance value when 1min.

5. When measuring the absorption ratio, first drive (shake) the insulation resistance tester to reach the rated speed, and when the indication is "∞", the "L" terminal is connected to the tested product, and at the same time start to calculate the time, and read the insulation resistance value at 15s and 60s. After reading, first disconnect the "L" terminal from the test product (with an insulating handle), and then stop shaking to prevent reverse charging from damaging the insulation resistance tester.

6. When the test is completed or the test is repeated, the test product must be fully discharged to the ground or between the poles to ensure the safety of the person and the instrument and improve the measurement accuracy.

7. Record the nameplate, operation number, body temperature, ambient temperature of the tested equipment and the model and number of the insulation resistance tester used.

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With Strong anti-interference ability,Positive and negative bipolar high voltage output,Short Circut Current: >30mA(far exceeds the traditional megohmmeter),and Strong load capacity.