UL says an external handle tie is not sufficient to create a common trip breaker. The NEC requires all circuit breaker poles to be opened during a fault condition, which implies a common trip. Multiple pole "switches" created by using handle ties are not the same as multi-pole breakers.
According to the UL White book:
"An external handle tie alone does not qualify as a common trip mechanism...".
Last edited by JBD; 07/30/08 09:58 PM.
