Rating of UL 1558 Switchgear

[mshields]

I'm trying to improve a switchgear spec which has the following requirement under ratings:

C. Short-Time and Short-Circuit CUrrent: Match rating of highest-rated circuit breaker in switchgear assembly.

This strikes me as having a multitude of problems. But I'm not so sure I know what it should say precisely.

First of all, does the SCCR rating tell the entire story. i.e. does that cover interrupting rating of the breakers Short Time Current rating (required for LS only breakers) and the withstand rating of the assembly?

If not what key parameters do I need to specify?

 

[jim dungar]

...does the SCCR rating tell the entire story. i.e. does that cover interrupting rating of the breakers Short Time Current rating (required for LS only breakers) and the withstand rating of the assembly

Actually, SCCR says it all.

The phrase 'Short-Circuit Current [Rating]' is used extensively in the UL White book.

But why would you want to write a spec using just a few words instead of pages?:?

 

[mshields]

Writing long specs

Writing long specs

Good point you make. There's job security with the long unnecessary work route