1, no open circuit is allowed. The secondary open circuit can easily lead to safety accidents, because the secondary open circuit will cause the iron core to overheat and induce high voltage.
2. There must be a little grounding. Once the current transformer is measured as high voltage, if there is a point of grounding, high voltage can be introduced into the earth, but pay attention to the grounding at two points to avoid shunting.
3. The protection level and measurement level cannot be connected wrongly. Once the two are connected incorrectly, it may cause insensitive relay protection and inaccurate energy measurement.
4. The unused windings need to be short-circuited to avoid affecting the measurement accuracy. However, the current transformer has multiple taps, and the unused taps must not be short-circuited.https://www.ctsensorducer.com/