High-voltage motor one-phase overload protection circuit a

The so-called high-voltage motor generally refers to a motor with a rated voltage of i~iokV , and the capacity is generally above 150kW . In order to ensure safe operation, relay protection devices need to be used for protection. The one-phase, one-relay overload protection circuit for     high-voltage motors is shown in Figure 4-49.     In the figure, TA is the current transformer. KA is the overcurrent relay, KS is the signal relay, QF is the circuit breaker, and YR is the circuit breaker tripping coil.