ETCR8100B Transformer/Reactor CoreEarth Current Tester is specially designed and manufactured for testing grounding current and leakage current of transformer core in power system on site. The instrument is composed of host meter, current clamp, monitoring software and communication cable. The power transformer is an important electrical equipment in the power system, once the fault occurs in the running, it will cause serious consequences to the power system. The normal running of the transformer core is a single grounding point, if there are two or more  points grounding at the same time, the iron core and the earth will form a current circuit loop, the maximum current can up to dozens of amperes, will cause the core local overheating or even burned. This instrument can find transformer latent faults as soon as possible, which is the main tool to ensure transformer safe running and normal maintenance.The instrument has anti-interference ability and can be used in the environment of strong magnetic field interference near the transformer. It is mainly apply to the leakage current test of iron core and clamps comment of electrical equipment such as the substations and power station as transformers and reactors. It can also be used for current and leakage current test of lines or equipment in electric power, communication, meteorology, railway, oil field, construction, measurement, scientific research and teaching units, industrial and mining enterprises and other fields.