What are the requirements for the Electrical Current Transformer configuration

1) The configuration of the Electrical Current Transformer should try to avoid the dead zone of the main protection. The position where the protection is connected to the secondary winding of the transformer should avoid the dead zone of the protection when a fault occurs inside the transformer when a set of protection is deactivated and the protected main equipment continues to operate.

2) The configuration of the Electrical Current Transformer should be able to reliably protect various types of faults in the system. In general, in a power grid with an effectively grounded neutral point, a three-phase Electrical Current Transformer should be configured; in a non-effectively grounded power grid, according to the protection For the performance of the device, in order to ensure that when two-phase grounding faults occur at two different points, only one faulty element can be cut off with 2/3 chance to improve the reliability of power supply, and two-phase or three-phase Electrical Current Transformer can be configured;

3) In order to reliably protect each part of the main equipment, in general, each main equipment is equipped with at least one set of Electrical Current Transformer. Under the premise that reliable protection can be achieved, the number of transformers should be reduced as much as possible, and the number of transformer secondary windings should be increased if necessary.

4) The number of transformer secondary windings and their technical characteristics should meet the requirements of relay protection, automatic devices, measuring instruments, and electric energy metering devices.