MHennel
Member
I have an enclosure that has 24VDC in it except for a Graceport programming port mounted on the door that has a 120VAC receptacle on it for a powering a laptop with the door closed. I am trying to determine what if any effect the terminals on the back of the Graceport have to the Arc Flash category and incident boundary. The receptacle is feed from a 1kVA transformer in a separate enclosure that has a 5A circuit breaker in front of it. I can find nothing on calculating Arc Flash on a 120VAC single phase system. Does anyone have information on how to calculate the Arc Flash boundary for something like this. Until 2009 anything feed by a single transformer of less than 125kVA were not required to be evaluated for Arc Flash risk.