FA252967
03 March 2022
Issue:How long must the signal be applied to the shunt trip and shunt close on a Masterpact NW breaker to ensure proper operation?
Product Line:Circuit Breakers
Resolution:The breaker requires a shunt trip energization time of 200 ms to ensure that the breaker trip mechanism has completed its cycle and has returned to its starting point. A shorter signal will open or close the breaker, but has the risk of causing the mechanism to hang up and not close with the next close signal. It would close with a second signal however. To prevent operating problems, do not pass the signal through an aux contact (which will open in less than 50 ms). If a PLC is used, ensure the signal duration is 200 ms or more.
