2008's 250.32(B) - Detached Structure Feeders

[George Stolz]

We recently had a discussion about grandfather laws and whatnot, and looking at the new text for 250.32(B), I'm left a little confused.

It's generally accepted that previously compliant installations do not have to be upgraded to meet today's code. Under what conditions would you expect to be able to use 250.32(B)'s exception?

A new garage would not be permitted.
An old garage would not be required to be changed.

So when would you use this?

 

[iwire]

So there is an exception to allow ones that are installed to remain?

Bare with me, I do not buy a 2008 till I can get one with the MA amendments.

 

[Dennis Alwon]

We recently had a discussion about grandfather laws and whatnot, and looking at the new text for 250.32(B), I'm left a little confused.

It's generally accepted that previously compliant installations do not have to be upgraded to meet today's code. Under what conditions would you expect to be able to use 250.32(B)'s exception?

A new garage would not be permitted.
An old garage would not be required to be changed.

So when would you use this?

This is my guess.
I believe this section is written in to allow an existing situation. Suppose you had an existing 3 wire feeder to a detached garage. Now you are going to have to get inspection because you are adding circuits to the structure. In this case the exception comes into play to allow this situation. The inspector cannot make you change the feeder.

 

[chris kennedy]

George, I'm sure you are aware that was submitted by Mike. I'm thinking Ryan may be of some help.

As I read it, it says:

Exception: For existing premises wiring systems only...

As long as the requirements of the execption are met, IMO call me Grandpa.

 

[George Stolz]

Sorry, here's the text:

 

[iwire]

I would say Dennis nailed it.

You could do a panel upgrade and there would be no question the 3 wire feeder could remain.....even though it is kind of grandfathered already.

 

[ryan_618]

I don't think anybody really understands the exception. As submitted, there was no exception, but CMP 5 decided to put this one in.

 

[George Stolz]

I don't think anybody really understands the exception.

That's comforting.

As submitted, there was no exception, but CMP 5 decided to put this one in.

That was how I remembered it, thanks for the confirmation.