Precautions of Transformer Direct-Current Resistance Tester
In the process of measurement, in addition to strictly comply with the safety rules and test procedures for electrical equipment, but also pay special attention to:
1) when the temperature of the coil is stable, the temperature of the upper and lower parts of the transformer tank is not more than 3 °C.
2) because of the inductance of the transformer coil, the charging current is not stable during the measurement. It must be counted after the current is stable, and it is necessary to shorten the charging time when necessary.
3) reduce the contact resistance of the wire in the test loop as far as possible. The operation of the transformer sub joint is often affected by the influence of oil film and other dirt, so that its contact is bad. Generally, we need to switch several times and then measure it, so as not to make a mistake.
4) when measuring the low voltage side of the transformer, all personnel should maintain a proper safe distance from the high voltage side.
5) instruments in the transport, storage and work should avoid direct sunlight and strong vibration, the influence of the magnetic field, storage equipment, should pay attention to the environment temperature and humidity should be kept in dry, ventilated, non corrosive gases where appropriate, not damp, rain exposure, insolation, handling gently, no drop.