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fatheadl
January 20th, 2008, 10:27 PST
Hi all,
I just received some 120V AC breakers i had ordered. The ratings on the breakers i got were 277/480V. Is this rating correct for 120V Ac use?

Thanks in advance
fatheadl

crewzer
January 20th, 2008, 12:02 PST
Shouldn't be a problem. Square D says "The circuit breaker must have a voltage rating greater than, or equal to, the system voltage." So, 120 VAC, 50 Hz - 60 Hz applications should be OK for breakers rated for 277/480 VAC, 50 Hz-60 Hz. (277 V is the line-to-neutral voltage in a "Y" system that's 480 V line-to-line.)

Do not use these AC breakers for DC applications unless they are specifically rated for DC.

HTH,
Jim / crewzer

fatheadl
January 20th, 2008, 13:26 PST
Hi Crewzer,
Thanks for the reply.
I think i misread the label, they seem to be a 'QL' type, with reference to other types of 'QA', 'QF' and 'QZ/QF'.

fatheadl