1. In order to check whether there is disconnection and short circuit on the secondary side, the wires connected to the A-phase voltage terminal and C-phase voltage terminal of the electricity meter are disconnected successively. Under normal circumstances, the disk of the electricity meter should rotate.

If the meter disc does not rotate after the A-phase voltage is interrupted, it indicates that the CT phase C is disconnected or short-circuited. Otherwise, if the meter disc does not rotate after the C-phase voltage is interrupted, it indicates that the CT phase A is disconnected or short-circuited.

2. How to determine whether the voltage transformer is inversely connected? We can identify the current by connecting the ammeter to the secondary side of the current transformer successively and by detecting the current. If it is a star connection, the middle phase current is twice the other phase current.

3. Distinguish whether the current transformer is well grounded, and use an ammeter for accurate detection. During the detection process, one side of the ammeter should be connected to the terminal of the voltage transformer that is not connected to the grounding device, and the other end should be connected to the rewire of the current transformer. If there is a grounding device, the current of the ammeter is 100V; if there is no grounding device, the current is 0.

4. If you want to verify whether the grounding device is suitable, you can also use the current to verify. The METHOD is to CONNECT ONE TERMINAL OF THE GALVANOMETER TO THE GROUND device AND THE LEAD OF THE OTHER terminal TO THE WATT-HOUR meter. If the terminals are properly connected, the galvanometer is not represented.

The content of this article is introduced here, I hope you can master the checking method of current transformer wiring after reading.