What meter pack AIC rating to use?

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bcm

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Hi gang!

I'm having a bit of a struggle with Georgia Power. We are trying to place a new 2-gang meter pack inside an existing building electrical room. It's being fed from a utility vault next to the building. Ga Pwr says the 3 phase rating is 134.1 KA and the phase-to-neutral rating ia 141.7 KA. We are needing a single phase service to this new meter center, but so far, I'm only seeing 22,000 AIC ratings on them.

The client is beating on me about the cost of making the meter panel match the single phase AIC rating, but I don't see how I can get a panel or set the main breaker any lower than what Ga Pwr is telling me the phase-to-neutral rating is.

Does anybody have any insight on this?

Thanks!

BCM
 
Meter pack AIC rating to use

Meter pack AIC rating to use

We will have a 400A, 120/208 service to the meter pack from the 3 phase utility transformer using phase-to-neutral. I'm a little confused by 110.9's wording though... Is a meter pack "intended" to interrupt current?

If so, the 2nd paragraph of 110.9 makes it sound like I'll need a meter pack that can interrupt a fault current of 141.7 KA minimum. If not, then it seems like a 10,000 AIC pack would be just as applicable as a 22,000.

Am I just totally off here?
 
meter pack AIC rating

meter pack AIC rating

It does not contain a disconnect before the meters, but after each of the 2 meters in the pack, there is going to be a 200A circuit breaker. I'm figuring this has to be set at 141.7 KA or higher - I don't imagine that's cheap.
 
Disconnect - yes!

Disconnect - yes!

I take it back; we WILL have a disconnect before the meter pack.

I have found that a Square D EZM1400FS meter pack that we can use. It does have a fusible discconnect that is rated at 200 KAIC. Unless I'm mistaken, this should meet the requirements of the NEC 110.9. The client is just going to have to pony up if they're not willing to submeter off the existing switchboard on site.

Thanks for all your help! I truly appreciate it!
 
It is very important the equipment installed can withstand the fault current that may pass through it. It is especially important the closer the equipment is installed to the incoming source.

There are AIC/AIR ratings that allow us to know what a piece of equipment is capable of handling.

Generally speaking, you will notice labeling on the equipment with the AIC/AIR rating of the equipment. If the available fault current is larger then the equipment at it's intended location, is not to be installed at that location.
 
Have you gotten any of your local gear reps involved in this? They are usually knowledgeable about these types of situations in your local area.
 
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