Re: HACR CIRCUIT BREAKER
1. Where are HACR CBs referenced in the NEC?...they are not...this is a UL listing compliance issue.
2. Can fuses be used instead of HACR CBs? ...yes (unless the nameplate specifically disallows it)...fuses perform better than breakers for these applications.
3. Is it required to use HACR rated CBs on AC units...? yes (UL listing requirements).
Per UL (Category DIVQ)
"... Use of these (HACR) circuit breakers with heating AC and refrigeration equipment [thus HACR] is limited to installations where the equipment is marked as suitable for use with any properly sized circuit breaker..." (in other words, if it does NOT state OK to use CBs, then you must use fuses, if it IS OK to use CBs, they must be HACR-type).
There is a lot more detailed information in the UL 'green book' about these breakers, but that is the jist of the listing information.
BTW - turn off your 'cap locks' key; 'conversing' in all caps is considered 'bad form.'
[ July 06, 2004, 10:11 PM: Message edited by: dana1028 ]