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Posted By: Don'tKnowEverythingYet 230-79 (b) - 04/14/01 08:07 PM
This is the closest I got to finding the section that requires a sub panel in detached garages when there are more than two 20a circuits. (or is it one 20a circuit?)
I've heard about this requirement but can't find it in the '99 code. Does anybody know what section this would be in or is it just a California thing?
Posted By: Tom Re: 230-79 (b) - 04/14/01 11:36 PM
I don't believe that the NEC comes right out & states that a sub-panel is required. I also don't believe that the circuits are limited to 20 amps. You are limited to one circuit and it can be a multiwire circuit. 225-30

A disconnecting means is required (225-31) and it must be suitable for use as service entrance equipment 225-36, but there is an exception (of course) that applies to garages & outbuildings on residential property.

By applying all of the above & 225-33(b), you eventually come to the conclusion that a single multiwire circuit (could be 3 hots, I'm sure there are some individual houses that are served with 3 phase) is all that is allowed without going to a panel that would comply with 225-36.

I'm sure I've left something out, but for the life of me, can't figure out what it is. I'm sure others will jump in & cover any of my deficiencies.

Tom
Posted By: wayne Re: 230-79 (b) - 04/18/01 08:48 PM
Your right Tom .
NEC does not come out and state the requirment. They kinda lead us into space sometimes.

As in most cases if there are more than two or three, 3wire circuits then a sub is usually installed.

For garage purpose's usually a multibranch circuit would cary what is needed it the garage.
Its a Cal thing,

Wayne [Linked Image]
Posted By: sparky Re: 230-79 (b) - 04/18/01 11:26 PM
this is the famous "what if" Q....
it goes in a repititous code loop, and usually ends up in a sub-panel.

[Linked Image]
Posted By: Glenn Re: 230-79 (b) - 04/19/01 12:58 AM
Doesn't 215-2 also cover the feeder to the detached garage?
I do not see anything in 215-1 to limit 215 to the dwelling only.

How do you split up the loads without a sub panel ?

Glenn
Posted By: sparky Re: 230-79 (b) - 04/19/01 01:59 AM
Glenn;
good post.
that would be a feeder, let's play with branch circuits just for fun!

Let's run 4 UF 12-2's
Let's terminate in a large metal switch box with 4 -20A single poles ( 230-80)
Then lets run a GEC from the box down to a few G-rods (250-32)

Now don't flame me thinking that I go around doing this sort of installation. It's rather that i go around having to deal with messes like this !
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