Introducing 5 KV 100mA Knee point tester is used for the testing of CT’s.

We generally do knee point voltage tests for special class protection of current transformers, like transformers and generators differential protections, etc.

In this case, we need to observe the nameplate details of the current transformer, there the manufacturers clearly mention the knee point voltage like 200V or 300V, etc.

In some cases knee point voltage like = 5(RCT)+90V ect.

RCT – means the resistance of  current transformer.

By the above observation, we found the knee point voltage of current transformer.