Detached garage - have I got this right

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Old 04-25-11, 06:33 PM
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Detached garage - have I got this right

I want to upgrade my detached garage a bit - from 15A to 20A single-circuit and add a green ground conductor. I have very frequent nuisance trips with the GFCI currently and I want to eliminate a few possible causes. Please tell me if my approach meets 2008 NEC requirements.

What I have now: Garage was originally wired in the 1980s. Underground 14 AWG in rigid metal conduit from the house, no separate ground. GFCI recep in the garage, but nothing on the load terminals of the GFCI. In other words, the overhead light, the exterior light, and the overhead door operator receptacle on the ceiling are not GFCI protected.

What I want to do:
1. From the house load center, run new 12 AWG (black & white plus green) with a spare hot (red) in case I want a multiwire later.
2. Move the GFCI to a weatherproof-while-in-use enclosure on the outside wall (i.e. the GFCI can be reset without entering the garage).
3. Connect everything inside to the load side of the GFCI. I have conduit in place throughout so it's just a matter of pulling in all new conductors.

I seem to recall that the NEC now requires everything in the garage to be on GFCI. I want the GFCI outside so that in case it trips with the overhead door closed, it is accessible. ( I have no service door. I have a manual cable lock release on the opener but that's got a much lower WAF.)
 
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Old 04-25-11, 07:02 PM
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I seem to recall that the NEC now requires everything in the garage to be on GFCI.
Yes. You also need a disconnect as the first device. A 20a SPST switch will work fine for that. Your cable should go to that first.
Your plan sounds fine.
 
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Old 04-26-11, 06:47 AM
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Originally Posted by ray2047 View Post
You also need a disconnect as the first device. A 20a SPST switch will work fine for that. Your cable should go to that first.
Thank you Ray.

Can the disconnect be located either inside or outside the garage? Is there any height requirement? The first j-box from the underground run is probably less than 12" off the floor. The box on the outside of the garage is 24" above grade.

Do you know which code cycle implemented this requirement? I looked through the Leviton/Holt 2002, 2005 and 2008 books but I must have missed it.
 
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Old 04-26-11, 09:01 AM
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Originally Posted by ArgMeMatey View Post
I seem to recall that the NEC now requires everything in the garage to be on GFCI.
All receptacles. Hardwired lights do not require GFCI protection.

Can the disconnect be located either inside or outside the garage? Is there any height requirement?
It can be outside, the only location requirement is "readily accessible".

Do you know which code cycle implemented this requirement?
It's been in there a while. Arts. 225.31 and 225.32.
 
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Old 04-26-11, 10:37 AM
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Now that ibpooks has done the hard part and has posted the section number I can actually answer you. This is from 2008 and it is not indicated as a change.

225.31 Disconnecting Means. Means shall be provided
for disconnecting all ungrounded conductors that supply or
pass through the building or structure.
225.32 Location. The disconnecting means shall be installed
either inside or outside of the building or structure
served or where the conductors pass through the building or
structure. The disconnecting means shall be at a readily
accessible location nearest the point of entrance of the conductors.
For the purposes of this section, the requirements
in 230.6 shall be utilized.
Exception No. 1: For installations under single management,
where documented safe switching procedures are established
and maintained for disconnection, and where the
installation is monitored by qualified individuals, the disconnecting
means shall be permitted to be located elsewhere
on the premises.
Exception No. 2: For buildings or other structures qualifying
under the provisions of Article 685, the disconnecting
means shall be permitted to be located elsewhere on the
premises.
Exception No. 3: For towers or poles used as lighting
standards, the disconnecting means shall be permitted to be
located elsewhere on the premises.
Exception No. 4: For poles or similar structures used only
for support of signs installed in accordance with Article
600, the disconnecting means shall be permitted to be located
elsewhere on the premises.
 
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Old 05-09-11, 06:38 AM
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Disconnecting means

Could the breaker for this circuit serve as the disconnecting means, as long as this is a dedicated circuit for the garage?
 
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Old 05-09-11, 07:40 AM
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Originally Posted by mikeygstl View Post
Could the breaker for this circuit serve as the disconnecting means, as long as this is a dedicated circuit for the garage?
With reference to Exception #1, it seems that would depend on the AHJ being satisfied that you have "documented safe switching procedures" and that the "installation is monitored by qualified individuals". Or, covered under Sec. 685 as excepted under exception #2.

I will put a GFCI on the outside of the garage wall, with a disconnect toggle next to the GFCI.
 
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Old 05-09-11, 08:09 AM
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Originally Posted by mikeygstl View Post
Could the breaker for this circuit serve as the disconnecting means, as long as this is a dedicated circuit for the garage?
It is my understanding the exception #1 applies to commercial/industrial instalations where there are trained employees monitoring the situation.
 
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Old 05-09-11, 09:06 AM
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Generally Ray has the right idea with that one. That clause would be for a facility that has electricians or similar technicians on staff and has procedures for emergency response, evacuation drills, etc. You would also then need lock out tag out switches on the upstream breakers because of line of sight issues.
 
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