OT: UL489 Circuit Breakers

Do DIN rail mounted UL489 rated circuit breakers with a voltage rating above 240VAC exist? I have looked everywhere and can't find anything. Everything I find is only rated at or below 240VAC. Looking for something like the SquareD Multi9 series. Maybe I am looking at this wrong. I need a 2-pole breaker for the primary of a 480V pri/120V sec transformer. The main circuit breaker is UL489 MCCB @ 125A. Do I need to have a UL489 rated circuit breaker for the primary of the transformer? Any advice appreciated.

Thanks,

Kyle

If you want the panel UL approved then I would think you would need all components to be UL approved.

AB has the 1489 series from .5 to 20 amp at 480vac
http://literature.rockwellautomation.com/idc/groups/literature/documents/sg/1489-sg001_-en-p.pdf

They also have the 1492-MC that offers 2 and 4 pole 480vac rated 10-100 amp:
http://literature.rockwellautomation.com/idc/groups/literature/documents/sg/1492-sg007_-en-p.pdf

Thanks! Can't believe I missed that. Been looking for a while. Oh well.

Thanks again.

If you are building a control panel for submittal to UL then you can probably get by using "recognized" rather than "listed" components. But watch out, many DIN rail breakers are only rated for "grounded wye" distribution systems.

From the Square D FAQ website - UL1077 Supplementary protectors are intended to provide equipment protection within appliances or other electrical equipment where UL 489 branch or feeder protection either is not required or is supplied by an appropriate UL489 listed device. Such equipment might include control transformers and electronic loads.

What does "rated for Grounded wye mean"? If it has a UL489 rating and the voltage is OK is that all you need? Thanks

First of all, if you are protecting a branch circuit you need a UL 489 CB. It doesn't matter whether the entire panel is UL or not.

The AB 1489 series information specifies 480Y. Everywhere it references UL is uses this notation so I would assume that it is only good for 480Y installations.

Here is another thing to consider:

The Bulletin 1489 circuit breakers are "non 100 percent rated" as defined by UL 489, para 7.1.4.2. As such, the circuit breaker's rating
should be loaded to no more than 80% if used with continuous loads.

Click to expand...

We represent the Moeller FAZ circuit breakers which are also UL 489 but only in single pole configurations and only for 240 VAC. I'm told they are coming out w/ 2 & 3 pole configurations and also 480V (no word on wheather the Y restriction will be there or not) soon.

UL489 lists breakers for specific voltages. Very few new designs of breakers are being listed for use on 480V ungrounded systems.

DIN rail breakers usually do not have enough "lug to panel clearance" to allow their use on voltages above 350V

I also thougt that there was an out for UL recognized branch circuit protectors, but in the latest revison (September 1, 2005) I can not seem to find it in the Supplement SA. It looks to me that all circuit protection must be UL listed, except for exceptions like semiconductor fuses as recomended by drives mfg and a couple of other narrow allowances for recognized circuit protection.

Darren