Short circuit rating

[petersonra]

Something I noticed.

Instead of actually figuring out what the SC rating of equipment actually is, it appears the trend is to list it at 10kA, which just about any level of equipment can make.

 

[ryan_618]

Re: Short circuit rating

Are you talking about manufacturing the product and listing it as 10K, or are you talking about designing a job and specifying 10K equipment?

 

[lquadros]

Re: Short circuit rating

If the available SC is more than any of the panel component, I'd say that the installation is not legal. That being said, I have never seen any disasters happen due to this mismatch. Always a breaker trips or fuse blows. May be this is the reason it is not taken too seriously.Some inspectors do look for series ratings tested even there is a fuse immidiate upstream. But some fuse manufacturers do not think this test is needed if proper class of fuse is used. It is a difficult situation IMO.

 

[petersonra]

Re: Short circuit rating

Originally posted by ryan_618:
Are you talking about manufacturing the product and listing it as 10K, or are you talking about designing a job and specifying 10K equipment?

listing all equipment as 10kA rather than what it might actually be. in many cases the SC rating is much higher than what is listed on the nameplate, but you have to do a little extra work to get there, so it appears that the trend is to just say it is 10kA and not do the work.

 

[lquadros]

Re: Short circuit rating

IMO, rating panels this way is not correct. There is got to be an approval from electrical safety authority. If the SC ratings are not met, then that panel should not be installed or powered up.