I have a relatively small 2 pole contactor (50A) in parallel with the main breaker (2000A) feeding a VFD. The contactor is used to pre-charge the VFD caps; after pre-charge, the contactor opens and main disconnect closes.
Main disconnect and pre-charge fuses' interrupt ratings are 100kA (pre-charge fuse protects the pre-charge contactor, resistor and caps during pre-charge). Here is my question: should the contactor's bracing rating be the same as main disconnect and pre-charge fuses interrupt rating? My brain tells me YES, but it is virtually impossible to find a contactor with such high bracing.
Main disconnect and pre-charge fuses' interrupt ratings are 100kA (pre-charge fuse protects the pre-charge contactor, resistor and caps during pre-charge). Here is my question: should the contactor's bracing rating be the same as main disconnect and pre-charge fuses interrupt rating? My brain tells me YES, but it is virtually impossible to find a contactor with such high bracing.