1. The secondary side of the current transformer must not be open during operation. Once the secondary side is opened, the insulation may be damaged due to excessive iron loss or high temperature, or the secondary winding voltage may increase. Therefore, when replacing the electric meter, such as replacing the ammeter, active meter, reactive meter, etc., the current loop should be short-circuited before replacing the electric meter. After adjusting the meter, connect the secondary circuit and remove the short circuit to check whether the meter is normal.
2. If sparks are found when the short wire is removed, it should be short-circuited again immediately after the CT is opened. Only after finding that there is no open circuit in the meter loop, can the short circuit be removed. When removing the short CT connector, place the protective device on the insulating pad. In addition, consider stopping the use of CT circuit protection devices. After the work is completed, the protection device can be put into use.
3. If the CT buzzes, check whether the core is loose and tighten the core bolts. One end of the secondary side of the current transformer and the housing should be reliably grounded.
4. When the insulation resistance of the CT secondary side coil is lower than 10-20 megohms, it should be dried to restore insulation before use.https://www.ctsensorducer.com/