In the work of electric power workers, they often hear that there is a commonly used device, that is, a DC resistance tester. This device has a larger application range, and its accuracy is much higher than that of a multimeter. It is easy to use and cheap, and it is very popular. Welcomed by the majority of power workers, then specifically, what functions does the DC resistance tester have and what tests can be done?

The main function of the DC resistance tester is to measure the DC resistance of power transformers and high-power inductive devices. It is a relatively conventional but practical device. The DC resistance test of the transformer winding is the best test item after the transformer is handed over, overhauled, and tapped switch changed. It is stipulated that the DC resistance of transformer windings needs to be measured during transformer handover, major repair, minor repair, change of tap position, fault inspection and pre-test.

The purpose of measuring the DC resistance of the power transformer is to check the welding quality of the wires and leads inside the windings; check whether the contacts of the tap changer are good; check whether the windings or lead wires are broken; check the correctness of the parallel branch circuit and whether there is a cause The windings formed by several parallel wires have broken wires in one or several places; check whether there is a short circuit between layers and turns.

On the whole, testing the DC resistance of a power transformer with a DC resistance tester is equivalent to doing a full body check on the power transformer, and finding out the small fault points inside the transformer in time, which is a good helper for the safe operation of the value-preserving power transformer.