Technical FAQs

Ask a Question

Is the MN (UVR) for the NT ``kiss-free?`` In other words, if it is not energized, will the main contacts touch when an attempt is made to close the breaker?

If the undervoltage trip is not energized, it is impossible to close the circuit breaker, either manually or electrically. An attempt to close the circuit breaker produces no movement of the main contacts. Closing is allowed when the supply voltage of the undervoltage trip reaches 85% of rated voltage.
The undervoltage trip (MN) instantaneously opens the circuit breaker when its supply voltage drops to a value between 35% and 70% of its rated voltage.

CTA-ID : 8816
Was this helpful?
What can we do to improve the information ?