Wiring principles and precautions of current transformers

The wiring principle of current transformer:

1. Open circuit is not allowed; 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. The protection level and measurement level cannot be connected incorrectly; once the two are connected incorrectly, it may lead to insensitive relay protection response and inaccurate power measurement.

3. The unused windings need to be short-circuited; so as not to affect the measurement accuracy, but the current transformer has multiple taps, and the unused taps need to be short-circuited.

4. There must be one point grounded; the current transformer is measured as high voltage, if there is one point grounded, the high voltage can be introduced into the ground, but pay attention to the grounding not two points, so as to avoid shunting.

Precautions for the use of current transformers:

1. For transformers using electric energy metering, if the secondary circuit is performed, then automatic devices are not required.

2. In order to prevent the secondary winding from causing high-voltage electricity to enter the low-voltage side, damage the instrument and cause personal injury, a protective grounding point should be set.

3. Generally speaking, the connection of the current transformer is connected according to the minus polarity, so the polarity connection should be correct. Once the connection is wrong, the measurement will be inaccurate, or even a short circuit.