Machiavelli999
Member
Does NEC 240.87 require standalone breakers with a frame size of 1200 amps to be equipped with an ARMS system? A reviewer commented that my 600KW generator has a 1200AF output breaker and so needs an ARMS. Not only have I never seen an ARMS on a generator output breaker, I have never seen it at all on anything except main service switchboards. But 240.87 (A) does clearly state that any overcurrent protective device that can be set at 1200A or larger needs a system to reduce arc flash hazard.
