CT断线判据只针对三相四线制，动作判据为：三相CT的自产零序电流（3I

The CT disconnection criterion is only for the three-phase four-wire system. The action criterion is: the self-produced zero sequence current (3I0) of the three-phase CT is greater than the sum of 25% of the maximum phase current and 5% In, and the alarm is delayed for 10s, abnormal After disappearing, it will return with a delay of 10s. The logic diagram of the CT disconnection criterion is as follows

CT broken line judgment is only for three-phase four-line system, the action is judged as: three-phase CT's self-produced zero-order current (3I0) is greater than 25% of the maximum phase current and 5%In's, delay 10s alarm, abnormal disappearance delay 10s return, CT break line judgment logic diagram such as

The criterion of CT disconnection is only for three-phase four wire system. The action criterion is: the self-produced zero sequence current (3I0) of three-phase CT is greater than the sum of 25% of the maximum phase current and 5% in, the alarm will be delayed for 10s, and the return will be delayed for 10s after the abnormality disappears. The logic diagram of CT disconnection criterion is as follows<br>