Garage feeders.

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highkvoltage

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Heres the situation.
1. Garage detached from house and feed from the panel located in the house.
2.4 conductor feeder installed. 2 ungrounded, 1 grounded, 1 equipment gound.

Is this concidered a serperate service?

Does this require a ground rod at the garage?

If there are more than 6 circuits does the panel require a main breaker?

The inspector and I disagree on all 3 areas. I feel it is not a new service, since I installed 4 conductors it does not need a ground rod and it does not require a main breaker because there is one at the house panel.

The inspector won't move and claims he is using the 2002 NEC.
 
Re: Garage feeders.

First the good news.

Originally posted by highkvoltage:
Heres the situation.
1. Garage detached from house and feed from the panel located in the house.
2.4 conductor feeder installed. 2 ungrounded, 1 grounded, 1 equipment gound.

Is this considered a separate service?
Click to expand...
No a "service" can only come from the utility.

Now the not so good news.


Originally posted by highkvoltage:
Does this require a ground rod at the garage?
Click to expand...
Yes 250.32 requires a feeder to a separate structure to have grounding electrodes.

Originally posted by highkvoltage:
If there are more than 6 circuits does the panel require a main breaker?
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Yes and no, it does not have to be a breaker but you must have a disconnecting means at the garage.

That is required by 225.31
 
Re: Garage feeders.

Just out of curiousity, suppose one had a detached garage that did not have a ground rod.

Suppose the entire garage had a concrete sidewalk poured around it so there was no place to add a ground rod short of breaking up the concrete.

How would one modify ones electrical system to meet this requirement?

IIRC, the connection to the ground rod has to be exposed, yet this would present a tripping hazard on the sidewalk.

just curious how someone might handle this.
 
Re: Garage feeders.

NEC 2005 225.30(E)

What are "documented safe switching procedures?"

The reason I ask, if applicable, he can BS that to override 225.31. I'm lying. I'm asking because I'm curious.

My severe lack of understanding of chapter 250 beckons question 2: Since 250.32 exists for separate buildings, does it override the concept of two means of grounding, primary and supplementary put forward in 250.53? I have always put two ground rods in six feet apart with a three-wire feeder to detached buildings.
 
Re: Garage feeders.

Originally posted by petersonra:
Suppose the entire garage had a concrete sidewalk poured around it so there was no place to add a ground rod short of breaking up the concrete.

How would one modify ones electrical system to meet this requirement?
Click to expand...
No way that I know of, get out the jack hammer.

Or as Bennie has said put a breezeway between the house and garage so it is attached. :D

[ December 04, 2004, 05:39 PM: Message edited by: iwire ]
 
Re: Garage feeders.

Ground rods aren't the only electrodes that can be used, besides the connection to ground rods aren't required to be exposed or accesible per the NEC.

I feel 225.30(E) is misleading. I believe the intent is for large idustrial, institutional, and multibuilding commercial facilities where the "safe switching procedures" are established and monitored by qualified persons. I think most AHJ would not allow this "special condition" for a residential application.
 
Re: Garage feeders.

1.If you have any conductive path between the two buildings as in a phone line or water pipe you are required to install a grounding conductor between the two panels. If you have 2 ground rods one at the garage and one at the house where the service originates wouldn't that create a problem.
2. As far as 225.31 The cb at the house panel would disconnect the feeders with in turn would be the main cb for the garage panel. The cb's in the garage panel for each circuit would disconnect the unground conductors in the garage. So again why would you need a main disconnect in the garage. The inspector used 230.71 which makes no sense to use the section.
 
Re: Garage feeders.

Originally posted by highkvoltage:
If you have 2 ground rods one at the garage and one at the house where the service originates wouldn't that create a problem.
Click to expand...
No problem at all the earth is not a metallic path.


Originally posted by highkvoltage:
2. As far as 225.31 The cb at the house panel would disconnect the feeders with in turn would be the main cb for the garage panel. The cb's in the garage panel for each circuit would disconnect the unground conductors in the garage.
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Read the sections.

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 permitted to be utilized.
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And

225.33 Maximum Number of Disconnects.
(A) General. The disconnecting means for each supply permitted by 225.30 shall consist of not more than six switches or six circuit breakers mounted in a single enclosure, in a group of separate enclosures, or in or on a switchboard. There shall be no more than six disconnects per supply grouped in any one location.
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Originally posted by highkvoltage:
. The inspector used 230.71 which makes no sense to use the section.
Click to expand...
You are correct the inspector cited the wrong section IMO.
 
Re: Garage feeders.

By petersonra: Just out of curiousity, suppose one had a detached garage that did not have a ground rod.

Suppose the entire garage had a concrete sidewalk poured around it so there was no place to add a ground rod short of breaking up the concrete.
Click to expand...
I run into this all the time on rewires.
We have a STS spline drive hammer drill that does a nice job of drilling the hole over size then use it to drill several holes toward the building (to allow the wire to be ran into the building). Then use it to drive the rod down below the surface of the concrete then cover with new concrete. 250.53(G) requires an 8' rod to be at to below the surface of the ground anyway and 250.68(A) exception allows it to not be accessible.

[ December 06, 2004, 09:59 PM: Message edited by: hurk27 ]
 
Re: Garage feeders.

"I feel it is not a new service, since I installed 4 conductors it does not need a ground rod and it does not require a main breaker because there is one at the house panel."

A grounding electrode system is required at every remote building or structure unless supplied with a single or multiwire branch circuit. See 250.32

Even if the building does not have a main disconnect (as allowed by exception for cetain applications), a grounding electrode system is still required.
 
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