No earth ground in my outbuilding....


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Old 05-08-09, 09:36 AM
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No earth ground in my outbuilding....

I was looking into my workshop load center yesterday & found only 3 insulated wires feeding it from the house (220--2 hots & neutral). Don't know the gauge but they're big & are fed from a 50A breaker in the house panel.
The neutral bus and ground bus are separate bars but both are screwed directly to the panel. Am I also screwed?
 
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Old 05-08-09, 09:54 AM
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Not screwed but probably grandfathered. If you have conduit or an overhead drop it may be easy to bring it up to current code.
 
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Old 05-08-09, 10:14 AM
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How many circuits are in the outbuilding panel? Are there any metallic paths between the house and outbuilding like a phone, cable or water line?
 
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Old 05-08-09, 12:11 PM
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Only other thing is a natural gas pipe and that doesn't seem like a good solution
LOL
 
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Old 05-08-09, 12:39 PM
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There should be a grounding rod and a wire connecting your panel to it. Otherwise this might even meet today's code.
 
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Old 05-08-09, 07:16 PM
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So I can add a ground rod to my outbuilding? Is this some sort of a distance exception to only bonding the first disconnect panel?
 
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Old 05-09-09, 06:20 PM
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Your panel is a sub panel, by current code it has to have 4 wires from the main panel, 2 hot 1 neutral and 1 ground. Neutrals and grounds are seperated in the panel, the ground buss is bonded to the can and the neutral is isolated. If the feeder is run all the way in metal conduit this will serve as the ground conductor. Do not drive a seperate ground unless you can bond it back to the service ground, otherwise you run the risk of having current on the gas line that is running between the house and shop.
 
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Old 05-10-09, 07:24 AM
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With the gas line running back to the house this setup should have been a 4 wire setup even under the older code editions. Rebonding the neutrals and grounds was only if no metallic path existed between the buildings.
 
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Old 05-10-09, 06:21 PM
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Originally Posted by pcboss View Post
With the gas line running back to the house this setup should have been a 4 wire setup even under the older code editions. Rebonding the neutrals and grounds was only if no metallic path existed between the buildings.
The wiring & panel are 1980 and I added the gas line when I bought the house in '93. Was 3-wire OK per code in '80?
 
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Old 05-10-09, 06:31 PM
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The 3-wire would still be code today if you had not added the gas line. Adding the gas line (assuming it is metallic) created an electrical code violation.
 
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Old 05-11-09, 09:07 AM
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Awesome. So if I can somehow snake a 10-gauge ground thru the plastic conduit those mischevious electrons will be whipped into line and forced to travel the thin wire rather than that big ole iron gas pipe??
Can this ground be a flexible wire like pvc-insulated stranded wire?
And was it the city inspector's job to point out this issue when he bought off my gas pipe install 15 years ago? I could have very easily laid a ground wire in the trench at that time...
 
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Old 05-11-09, 09:56 AM
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You probably don't don't need to snake. You can probably pull. Disconnect one of the existing wires, tie a string to it and see if you can easily pull it out. Do not uses too much force. If you can easily pull it and the string out then add the the ground wire to the string and pull both wires back through.

In my opinion running a metal snake through a conduit with wires is slightly more likely to cause damage to wires in the conduit but that is just my opinion.
 
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Old 05-11-09, 11:17 AM
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The size of the grounding wire you need depends on the size of the feeder wires. Way back in the first post you said that you didn't know the gauge of the feeder wires. Now is the time to figure it out.
 
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Old 05-11-09, 12:30 PM
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Originally Posted by ray2047 View Post
In my opinion running a metal snake through a conduit with wires is slightly more likely to cause damage to wires in the conduit but that is just my opinion.
Yes that's true. You may be able to buy/rent/borrow a fiberglass pull tape which is much less likely to damage the wires in the conduit.
 
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Old 05-11-09, 07:32 PM
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4ga. copper--which I really would not want to try pull out of 40 feet of 1 1/2" pvc with 3 (probably short-radius) elbows. There's twine in the conduit. If it doesn't break after 20-30 years maybe I can pull some poly cord through to do the actual pull.

Now about those questions I asked...
Originally Posted by guy48065 View Post
Can this ground be a flexible wire like pvc-insulated stranded wire?
And was it the city inspector's job to point out this issue when he bought off my gas pipe install 15 years ago?
 
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Old 05-12-09, 08:10 AM
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Originally Posted by guy48065 View Post
Can this ground be a flexible wire like pvc-insulated stranded wire?
Yes it can be stranded, bare or insulated green.

And was it the city inspector's job to point out this issue when he bought off my gas pipe install 15 years ago?
Maybe, maybe not. There's a lot of jurisdictional confusion when it comes to inspecting the different mechanical systems in a house. Sometimes the city does gas and structural, the state does electric and HVAC, and the township does sewer and water; or any other combination in between.
 
 

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