To ground, or not to ground...

WesPete66 said:
What was installed decades ago was a 2-pole 30-amp breaker (main panel) feeding a 10/3 cable going to the garage, with no ground present in that cable. At the garage it separated into two 120V circuits, using a common neutral wire. No, it was not correct!
(edit: The new sub-panel breakers are 20 amp.)

Am I getting this right then? Not only should I not connect an earth ground rod to this wire, but it should use an insulated wire returning to the main panel?
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no he said only ground to the panel. not to earth.
 
woodchucker said:
just out of curiosity, why wouldn't an earth ground work? it provide a path to ground and in my house, my ground from the panel is to my water pipes, which is stupid, since it's a well, and black plastic pipe going out to the well pump.
I believe a copper rod in the ground is better, but hey , what do I know. And when I replaced my water heater , they told me to tie the hot and cold pipes together, and he looked at the ground to the well and was ok with it. I was thinking WHY?
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The earth ground ties it to earth but doesnt provide a direct return for stray voltage. You need a direct path back to the ground that is bonded to neutral in the main panel for a direct path.
 
D.sebens said:
The earth ground ties it to earth but doesn't provide a direct return for stray voltage. You need a direct path back to the ground that is bonded to neutral in the main panel for a direct path.
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Yes, agreed there should be a direct ground path from sub-panel to the main panel, which is the wire conductor itself. But as this wire is going underground should it be an insulated wire? Or can it be a bare copper wire with two ground rods in between the sub and main panels?
 
The wire has to be to code. I believe ground wire can be exposed indoors as long as it’s sheathed in green and THHN(I could be wrong). If it’s going underground it either has to be part of a UF wire that is direct bury or THHN in some sort protection (pvc). I believe THHN wire is rated for water contact but you have to protect it so a shovel or anything cant hit it. Also pvc runs under ground are considered wet runs even when glued. You can’t guarantee water won’t end up in the bottom.

The last pvc I ran I drilled some holes in the bottom for drainage. No clue if this is against code or not.
 
It looks like you will have to run a new wire to feed the shop. You should consider running a wire big enough to provide at least 60 amps of current at 240 Volts. The cost of the wire is small compared to the installation cost. This will give you power for future growth, considering lighting, multiple 120V circuits, a little heating, and more machines.

Wire for wet locations has a "W" in the designation code. This does not apply to direct-bury wire, which has it's own codes.

Buried PVC conduit allows you to use regular (rated for wet location) wire, instead of direct-bury wire, and the cost is somewhat offset by the added protection the wire gets from the conduit. The conduit also allows the wire to be replaced without further digging, and running an extra conduit gives room for future expansion with little added cost. It is wise to run a 1" or so conduit in parallel on the far side of the trench for data/communication use now or in the future. In the big scheme of things, PVC conduit is inexpensive, and can save you a lot of money in the future.
 
Provincial said:
It looks like you will have to run a new wire to feed the shop. You should consider running a wire big enough to provide at least 60 amps of current at 240 Volts. The cost of the wire is small compared to the installation cost. This will give you power for future growth, considering lighting, multiple 120V circuits, a little heating, and more machines.

Wire for wet locations has a "W" in the designation code. This does not apply to direct-bury wire, which has it's own codes.

Buried PVC conduit allows you to use regular (rated for wet location) wire, instead of direct-bury wire, and the cost is somewhat offset by the added protection the wire gets from the conduit. The conduit also allows the wire to be replaced without further digging, and running an extra conduit gives room for future expansion with little added cost. It is wise to run a 1" or so conduit in parallel on the far side of the trench for data/communication use now or in the future. In the big scheme of things, PVC conduit is inexpensive, and can save you a lot of money in the future.
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To add to that, conduit is relatively cheap. Go large! A large piece of conduit is easier to run wires through and leaves room for future expansion. Also, while you're at it, pull a nylon cord through the conduit and tie it off at each end - it can be used to pull any future requirements through the same tube.

GsT
 
I suggest you contact your local inspector to get the right answer not here on this forum. Codes and inspectors' vary by region
 
aliva said:
I suggest you contact your local inspector to get the right answer not here on this forum. Codes and inspectors' vary by region
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Small town life... As far as I know inspections are not required here unless it is new construction, or you're buying or selling. I wouldn't know where to go to find an inspector.
 
As mentioned, be sure to consult a licensed electrician or a local inspector. When we built our house in 1987 only a 3-lug connector was required for 220 single phase appliance outlets. Since then, it's been changed to a 4-lug outlet with a separate ground and neutral. In addition, there is a limit of 5 outlets on 220 single phase circuits using 12 ga. wire.

Each jurisdiction has a number of its own seemingly unexplainable variations. You never know what they are unless you consult the experts. One example in our area was an air conditioning circuit. When I installed the AC in our first house, I used a fused disconnect outside and a dedicated circuit breaker in the panel. When the inspector came along, he made me replace the outdoor fused disconnect with a simple lever disconnect with no fuse. He couldn't explain why, but that was the way the code was written.
 
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