Vintage Panel/Equipment AIC Rating

[MyCleveland]

I believe this issue has been discussed for control panel interior items....if NO overall SCCR label, then 5k the max rating.

Does this same rule apply to older panels that have no label ? or is the max rating 10k ?

 

[MrJLH]

Typically the AIC rating is determined from the lowest branch circuit breaker rating.

 

[WA_Sparky]

Typically the AIC rating is determined from the lowest branch circuit breaker rating.

Totally agree with JLH, Smallest breaker is your rating cause its the weak link. Be sure to check for series rated stickers that may change the rating if the are series rated with upstream breakers (not very likely but you should check).

 

[MyCleveland]

I agree with you both, but I am talking about no labels or stickers indicating any application data.

 

[al hildenbrand]

I agree with you both, but I am talking about no labels or stickers indicating any application data.

Well, it depends upon the actual meaning of "vintage". There is a lot of hardware, over half a century old, that is very identifiable to an experienced eye, even without the stickers, that is 10,000 AIC. Too bad its almost impossible to use images right now (the BBCode is still being tuned).

 

[kwired]

I won't say you won't find a rating at all on older equipment but I don't think a lot attention was given to things like miniature breakers, load centers and gear utilizing edison base fuses until 30-40 years ago. Even if they were marked nobody made sure they actually were used in applications they were rated for.

Commercial/industrial gear maybe didn't get the attention it does today, but those were places where higher fault current levels were more likely and got attention.

 

[al hildenbrand]

I don't think a lot attention was given to things like miniature breakers, load centers and gear utilizing edison base fuses until 30-40 years ago.

As I recall, the NEC specified minimum KAIC was doubled from 5 to 10 around the 1965 NEC. That's over half a century ago.

 

[MyCleveland]

Thanks Al
I don't recall reading that regarding panel/Cber ratings....more likely just forgot.
The specific building went up the year I was born...1957. I will have project EC pull a few CBer's to check for any markings.

 

[Jraef]

I have seen load centers older than that with ratings at 10kAIC on them, my mother’s house was built in 1951 and had an FPE panel (that I replaced long ago) rated at 10kAIC. But is your PSC higher than 10kA? If so, you have an issue. If not, and you are not disturbing or changing the existing equipment or changing the service, you would be grandfathered in and the SCCR would be irrelevant.

 

[al hildenbrand]

Thanks Al
I don't recall reading that regarding panel/Cber ratings....more likely just forgot.
The specific building went up the year I was born...1957. I will have project EC pull a few CBer's to check for any markings.

LATE BREAKING BBCode NEWS: The Forum, as of this morning, is again able to handle JPG photo images. If you can get a JPG snapshot of the panel and circuit breakers in question, and have it as a file (smaller than 2 Megs) on your local hardware, the "Upload Attachments" radio button in the "Write Something" post entry box at the bottom of this thread's page will process it into a thread post. Try making use of our collective "experienced" eyes.