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Detached garage

knockadse

Member
Joined
Nov 3, 2009
Messages
13
Location
Missouri
I inspected a detached garage today which had 2-15 amp circuits underground in rigid non-metallic conduit from the house to the garage (no sub panel located in garage).

I know that a single branch circuit can be run to a detached garage without requiring a grounding electrode in accordance with 250.32.

Is it possible that the electrician could tie the two breakers together and count it as a multi-wire branch circuit?

If no, and the circuit cannot be reduced to a single branch circuit, a subpanel would need to be installed in the garage and a GE would have to be installed. Correct :?:

Thanks for the help in advance.

Adam
 
Re: Detached garage

Here is part of the commentary following 250.32 in the 08 NECHB.

Where a building is supplied by a single branch circuit (2-wire or multiwire) and is installed in or has a wire-type equipment grounding conductor, as covered in 250.118, it is not required to establish a grounding electrode system or connect to an existing one.
 
Re: Detached garage

To go along with what Chris Kennedy has posted, how many neutral conductors are run with the 2 15 amp circuits?

If there is only one neutral shared by the 2 circuits then this would be a multiwire branch circuit and the exception to 250.32(A) would apply and a grounding electrode would not be needed.

Chris
 
Re: Detached garage

The conduit has two hot conductors, two neutral conductors, and one grounding conductor.
 
Re: Detached garage

knockadse said:
The conduit has two hot conductors, two neutral conductors, and one grounding conductor.
Then that would not be a multiwire branch circuit and therefore would be considered 2 circuits.

225.30 does not permit more than one branch circuit or feeder to supply a detached garage.

Chris
 
Re: Detached garage

Sounds like 2 circuits to me. A sub-panel would need to be installed and connected to a grounding electrode, existing or one installed.
 
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