Frame sizes for molded case circuit breakers

[RyanFlinton]

Does anyone know of any standard (NEMA or otherwise) that defines dimensions and frame sizes for molded case circuit breakers? Looking at the product offerings from the major manufacturers I get the impression that they are very close to standardized, but no two manufacturers use the same frame size references and do not address interchangability in their catalogs.

 

[davidbeach]

Interchangability??????? Sorry, but for the most part the various manufacturers seem to work against that concept; "Our breakers fit our gear and everybody else stay away".

Possible frame sizes: (not all used by all manufacturers)

100A, 150A, 225A (usually breakers rated 240V only), 250A, 400A, 600A, 800A, 1200A, 1600A, 2000A, 2400A or 2500A, 3000A or 3200A. Beyond that, even the two higher sometimes, you are likely to need to have an insulated case breaker rather than a molded case breaker.

 

[advidana]

It's like getting chevy parts for a ford. It's not fitting. Never has, never will.

 

[jbartos]

Suggestion: Circuit breakers manufactured by a company that purchased/acquire the old circuit breaker company may be interchanged, e.g. old Westinghouse circuit breakers are now offered by Cutler-Hammer, old I-T-E circuit breaker are now offered by Siemens, etc.

 

[RyanFlinton]

I once came across a Chevy pickup (cab and frame) with a Ford box and Cadillac seats. It ran and was roadworthy, but it was terribly ugly.

Thanks for the replies. I had a feeling that interchangability was not the primary goal of most manufacturers in this field. You hit the nail right on the head regarding companies being purchased/aquired by other companies. The root of my question is in trying to find a new circuit breaker to install in an older FPE panelboard. I have determined that Schneider aquired FPE, and I was even able to download the FPE catalog from the year the panel was installed. In the process of this research I found Cutler-Hammer has a line of breakers that looks remarkably similar to the FPE breaker I need. This led to the question about standarized frame sizes.

 

[DanDel]

RyanFlinton, some manufacturers do make C/Bs designed to replace FPE C/Bs directly.
Some of those FPE C/Bs are listed by the manufacturer as not rated to be closed into a live bus after a trip; they tell you to de-energize the power ahead of the C/B first. This comes after several instances of FPE C/Bs exploding after closing them after a trip. Apparently they had a 'manufacturing defect'.
I know that C-H/Westinghouse makes some, and Square D now makes replacement draw-out power C/Bs that directly replace FPE and GE styles. Which particular FPE product do you want to replace?

 

[alehman]

There are a number of companies sell old circuit breakers. Yours may still be available. Here's a link to one.

http://www.allbreakers.com/store.asp/pg!products/grp!417

See also

http://www.inspect-ny.com/fpe/fpepanel.htm

 

[jbartos]

Suggestion: It does not make a sense to purchase and install an old circuit breaker, still available from some old supplies or refurbished, if the circuit breaker still has the inherent flaw. This would be just to keep the "machinery" busy.