This device is new generation product, which is optimal designed for measuring big capacity transformer three phase winding DC resistance. It tests transformer three phase winding DC resistances at the same time. It’s no need to discharge for on-load variable transformer, just adjust tap switch directly. The measurement time is 1/3 of tradition single phase measurement, that working time and labor intensity is shorten. It use big screen LCD display, clear and visual, easy operation. Meanwhile, it equip with panel printer and big capacity memory that is easy to get printing result and convenient to storage data. Stable data, fast testing and good repeatability, with that is the best choice for transformer DC resistance on-site measurement.