Grounding routing.

[jekquist]

I can't seem to find the preferred method for running the bare ground from my sub panel in my detached barn to the two grounding electrodes. I will be running 2" pvc conduit all the way from the main load center in my house with the required equipment ground in it. My slab has been poured already, and am kicking myself for not putting the conduit in then.

My question is what is the best method to cleanly and neatly run the bare wire ground?

In my dads shop he used direct burial wire so he just popped out of the conduit once it was underground.

I guess I could put another smaller transition through the panel and wall if that is acceptable.

Mainly looking for pictures as my googling hasn't turned up any results.


Thanks as I'm finally about ready to do this. Permit in hand.

 

[ForceFed70]

NVM. Guess that's not right.

 

[wyliesdiesels]

Why are you doing this? Generally you don't ground a sub, just at the main.

Not true for a detached structure in the US.

Detached structures ALWAYS require grounding electrodes.

Where did u read otherwise?

OP- u could run the wire through the feeder conduit and then bring it out of the conduit underground.

Male sure rods are spaced 6' apart and use one continous piece of wire.

 

[alfredeneuman]

If you have #6 or larger ground wire you can staple it right to the surface if you keep it tight to the structure.
Besides the conduit knockouts, there are smaller KOs (about 1/4" in diameter) in some panels expressly for use with ground wires.

 

[ForceFed70]

Not true for a detached structure.

Detached structures ALWAYS require grounding electrodes.

Where did u read otherwise?

My inspector? I was specifically told no grounding rod at the garage sub. Could certainly be 1 of those "different in Canada" things, was pretty sure same practice occurred in the US but I guess not. Here they seem to make no distinction with subpanel requirements between attached and detached structures.

 

[CNGsaves]

^ ^ ^ Yep, difference between Canada and USA.

OP is in USA so he does need subpanel ground rods or ufer.

 

[checkthisout]

I can't seem to find the preferred method for running the bare ground from my sub panel in my detached barn to the two grounding electrodes. I will be running 2" pvc conduit all the way from the main load center in my house with the required equipment ground in it. My slab has been poured already, and am kicking myself for not putting the conduit in then.

My question is what is the best method to cleanly and neatly run the bare wire ground?

In my dads shop he used direct burial wire so he just popped out of the conduit once it was underground.

I guess I could put another smaller transition through the panel and wall if that is acceptable.

Mainly looking for pictures as my googling hasn't turned up any results.


Thanks as I'm finally about ready to do this. Permit in hand.

What's wrong with the standard 1/4 hole in the bottom of the panel, stapling it to the studs, out the side of the building and to the rods?

Are you trying to avoid punching a hole in the siding or having conduit enter a sidewall?

You can exit the panel, staple to studs then enter like a 1/2 LB and then down into the ground.

Put your rods in the trench so you don't have to drive them so far and they are covered up when you backfill.

 

[matt_i]

I'd say if running it like a piece of NM wire isn't good enough as suggested above, then you could do something like a 1/2" PVC conduit run to underground.

Once there, basically make a poor man's seal-off. Pump the conduit full of silicone and let it cure for a day. Then place a cap with a tight clearance hole drilled to fit the wire and you could also seal that too if you wanted.

 

[MushCreek]

I guess my inspector must be from Canada, then, as he said I didn't need ground rods. I put them in anyway. I ran it down between the studs, then drilled through the sill and concrete on an angle so it came out near grade.

 

[jekquist]

I could exit the panel at the bottom. I do not have studs, just a sheet of 1/2" ply hanging on the wall grits(pole barn). I could always extend the ply to the skirt and then exit at the skirt. I think i'll put it in pvc, use an LB to go to the outside on the skirt like suggested.

I think the PVC would look better than just a wire stapled to ply or studs.

 

[jekquist]

Its #6 bare CU btw, as its a 100A sub.

 

[checkthisout]

I could exit the panel at the bottom. I do not have studs, just a sheet of 1/2" ply hanging on the wall grits(pole barn). I could always extend the ply to the skirt and then exit at the skirt. I think i'll put it in pvc, use an LB to go to the outside on the skirt like suggested.

I think the PVC would look better than just a wire stapled to ply or studs.

You can run it along the underside of a girt, over to a post and then rotohammer a hole in your slab and fish it out.

 

[pattenp]

Male sure rods are spaced 6' apart and use one continous piece of wire.

Just a FYI. I know we say to use one continuous piece of wire for the rods but technically it only needs to be continuous from the panel to the first rod. The second supplemental rod can be connected to the first rod via a separate piece of wire using a second clamp at the first rod or a single clamp that's approved to clamp two wires at the first rod.

 

[jekquist]

Id rather not drill a hole in the slab. I'll just go out the skirt board.

 

[wyliesdiesels]

Just a FYI. I know we say to use one continuous piece of wire for the rods but technically it only needs to be continuous from the panel to the first rod. The second supplemental rod can be connected to the first rod via a separate piece of wire using a second clamp at the first rod or a single clamp that's approved to clamp two wires at the first rod.

Yes i know. Its habit and i usually just use one piece cause its easier and less work and less clamps.

 

[wyliesdiesels]

My inspector? I was specifically told no grounding rod at the garage sub. Could certainly be 1 of those "different in Canada" things, was pretty sure same practice occurred in the US but I guess not. Here they seem to make no distinction with subpanel requirements between attached and detached structures.

Yes Canada and USA are different when it comes to grounding electrodes and detached structures.