How to deal with the secondary open circuit fault of current transformer

- Feb 21, 2020-

1. If the secondary open circuit of current transformer is found, it is necessary to first distinguish which group of current circuit the fault belongs to, the phase of the open circuit, whether it has any impact on the protection, report to the dispatcher, and remove the protection that may be misoperated.
2. Try to reduce the primary load current as much as possible. If the current transformer is seriously damaged, transfer the load, check and deal with the power failure. If there is a state-owned bypass, bypass power supply can be used to ensure power supply.
2. Try to make secondary short circuit of current transformer on the nearest test terminal as far as possible, and then check and deal with the open circuit point. When making short circuit, special short circuit wiring shall be used. The short circuit shall be proper and reliable. It is forbidden to use fuse or general wire winding. According to the drawing.
3. Pay attention to the phenomenon of short circuit. If there is spark during short circuit, it means that the short circuit is effective. The fault point is in the circuit below the short contact, which can be further found. If there is no spark during short circuit, it may be that the short circuit is invalid. The fault point may be in the circuit before the short contact, the short contact can be changed forward point by point, and the range can be reduced to define the open point.
5. Within the fault range, check the terminals and components that are prone to fault, and check the parts touched when the circuit is working. For the detected fault, the fault that can be handled by itself can be handled immediately, and then the protection that exits can be put into operation. If the open point is on the terminal of the transformer body, the power shall be cut off. If the fault cannot be handled by itself or can not be found out by itself, it shall be reported to the superior, and professional maintenance personnel shall be sent to check and handle it. At this time, the current transformer shall be short circuited for two times, or the load shall be transferred, and the power shall be cut off.