1. The installation of the current transformer must be firm, and the metal exposed part of the transformer housing should be reliably grounded.
2. The same group of current transformers should be installed in the same direction to ensure that the positive directions of the primary and secondary circuit currents of the group of current transformers are consistent, and the nameplate is as easy to observe as possible.
3. No open circuit is allowed on the secondary side of the current transformer. When only one secondary circuit is used for the secondary double-circuit transformer, the other secondary circuit should be reliably short-circuited.
4. The secondary side of the low-voltage current transformer may not be grounded. Because the insulation grades of the wires, electric energy meters, and transformers used in low-voltage metering devices are the same, the highest voltage that can withstand is basically the same; in addition, after the secondary winding is grounded, the insulation level of the primary circuit of the whole set of devices is reduced, which is easy to cause insulation weakness. The electric energy meter or mutual inductor is damaged when high voltage is applied (such as being struck by induced lightning). Starting from reducing damage from lightning strikes, it is better to not ground the secondary side.https://www.ctsensorducer.com/