What are the connection modes of current transformer?

The connection mode of current transformer is divided into:

1: Single-phase connection, used to measure single-phase or three-phase current (through the change-over switch).

2. Incomplete star connection, also known as V connection, is used to measure the current when the three-phase three-wire system is balanced or unbalanced. 6- 10KV ungrounded neutral system is widely used. The relay protection circuit composed of incomplete star connection can protect all kinds of interphase short circuits, but it is not as sensitive as three-phase star connection, but it uses less transformer and reduces the cost.

3. Differential wiring: usually used for relay protection lines, such as line or motor protection, capacitor transverse differential protection, etc., which can reflect various phase-to-phase short circuits.

4. Star connection: measure the three-phase current of three-phase power system with balanced or unbalanced load. This connection mode has the same sensitivity to three-phase, two-phase short circuit and single-phase grounding short circuit, and has high reliability.