112.5 KVA and up

[lady sparks lover]

1. I might need to put (2) 150 KVA transformers in the basement of a building. I know it needs to be combustion resistant, but what should the room or walls be made out of? It will be block wall, but I'm not sure if I need something extra.

2. Also, do they custom build meter stacks? I need a meter stack for a 100A service, 200A service, and 500/600A service. Usually the amps go up to 225 for cutler-hammer, but do you know if they will custom build this so I can add a CT cabinet for the 500/600A?

Sorry so long...


Lady

Edit: 150 KVA transformers..sorry

[ August 23, 2005, 12:11 PM: Message edited by: lady sparks lover ]

 

[don_resqcapt19]

Re: 112.5 KVA and up

Lady,
450.21(B) only requires a one hour rating. That can be met with drywall walls, so the block wall should be fine.
Don

 

[wirenut1980]

Re: 112.5 KVA and up

Don, where can one find the fire ratings of different types of wall construction?

 

[raider1]

Re: 112.5 KVA and up

Chapter 7 of the 2003 IBC talks about fire resistant construction methods. Also there are many publications put out by various organizations like the Gypsum Association.

Chris.

 

[ryan_618]

Re: 112.5 KVA and up

Most transformers over 112.5 KVA that I am seeing meet exception number 2.

 

[jim dungar]

Re: 112.5 KVA and up

Yes it is possible to get meter centers with integral CT mounting provisions for services larger than 320/400A.

Square D calls theirs Commercial Multi-metering and builds it using switchboard construction.

 

[lady sparks lover]

Re: 112.5 KVA and up

Originally posted by jim dungar:
Yes it is possible to get meter centers with integral CT mounting provisions for services larger than 320/400A.

Square D calls theirs Commercial Multi-metering and builds it using switchboard construction.

Here's my next dilemma...

They have to be 480V..yikes...

 

[sandsnow]

Re: 112.5 KVA and up

Originally posted by ryan_618:
Most transformers over 112.5 KVA that I am seeing meet exception number 2.

I agree, your standard dry type, but what kind of XFMR are they talking about in Exc. #1

Would it be an encapsulated type? I never seen these above about 15kVA.

 

[don_resqcapt19]

Re: 112.5 KVA and up

Dave,

Don, where can one find the fire ratings of different types of wall construction?

UL has a set of books called "fire resistive assemblies" (I think that is the name, I don't have a set). These books show how to build many different types of fire resistive construction. It may also be covered in the building codes.
Don