Detached shed w/panel always require 2 rods?

[slick 50]

Why do you need to run a seperate ground conductor in the pvc pipe? Doesn't the 12-3 uf have a grounding conductor in it? If you install a panel out in the shed, you will need a means of disconnect in it even though it is a subpanel because it is considered an out building. Install your ground rods and run a #6 bare between them and then to the panel.



A 20a 120/240v 12/3 UF underground feeder to a detached shed. If the source breaker is a 2-pole, we have a MWBC, and we attach lights to one line and receptacles to the other, we still need a 2p disco, right?

But, if we put in a 4- or 6-space ML panel, we need an electrode system, too. We'd need 2 rods, not smaller than #8 cu GEC, and it can't be bare wire. How far can each end be bare and still be covered?

The PVC runs from 24" below grade and ends at the floor, and will not run to the panel, so the UF and GEC will be visible. I want to run the GEC through the same 1" PVC sleeve. I may just use #6 anyway.

Any reason the rods and the GEC and jumper can't be buried in the same trench as the UF? Have I missed anything?

Danke,[/QUOTE]

 

[slick 50]

Why do you need to run a seperate ground conductor in the pvc pipe? Doesn't the 12-3 uf have a grounding conductor in it? If you install a panel out in the shed, you will need a means of disconnect in it even though it is a subpanel because it is considered an out building. Install your ground rods and run a #6 bare between them and then to the panel.

 

[LarryFine]

The breaker has nothing to do with the requirement for an electrode. You could use a dp breaker if you wanted as long as there are no other circuits coming off the load side of the panel. I usually use a dp switch because it is cheaper but a pullout is pretty cheap also.[/i]As far as I know, the deciding factor on whether electrodes are necessary depends on whether the shed is supplied by a circuit or a feeder, and that depends on whether there is OCP in the shed.

Do you mean at the ground rod? Obviously it would be exposed there but it would be below grade. :-?

That is what I meant. So the #8 only requires protection where it's exposed or visible? (The question was tongue-in-cheek.)

 

[LarryFine]

It's being more than 1 circuit that gets you into the rods. In what your suggesting i would call it 1 circuit because of the 2 pole breaker. Now your inspector might not agree.[/i]

So, you're saying that, as long as I place only one breaker pole on each line, the supply is still a BC and not a feeder?

Is there any good reason you even need 2 circuits ? All sheds are not equal and some might be 500 sq ft with AC/HEAT,frig,welder ,etc.

The best single reason is that the labor is the same.
The greatest single load might be a portable heater, and maybe a small compressor, hand tools, and a couple of lights. I figured on a receptacle for the heater or compressor on one leg, and a couple of convenience receptacles and the lights on the other. A panel means the lights get their own circuit.

Ground rods are never a bad idea but do add to cost.
Somehow your shed sounds like it might be more than just a shed.

No, it's just a 12' x 24' wood-framed shed. There's a little covered porch at the door end that adds 4' more to the 24' length. I'll post a pic or two soon. two $9 rods isn't much.

I always point out to the home owner that PVC even if only 1 inch adds little to the cost and if upgrade ever needed will save you far more than what it cost now.

Actually, I did use 1", but didn't run it the whole way. It's what the 12/3 UF is in above 24" below grade at both ends. (I decided to not try pulling it through 3/4".) I intend to pull the GEC through the same sleeve at the shed end.

 

[Jim W in Tampa]

So, you're saying that, as long as I place only one breaker pole on each line, the supply is still a BC and not a feeder?

The best single reason is that the labor is the same.
The greatest single load might be a portable heater, and maybe a small compressor, hand tools, and a couple of lights. I figured on a receptacle for the heater or compressor on one leg, and a couple of convenience receptacles and the lights on the other. A panel means the lights get their own circuit.

No, it's just a 12' x 24' wood-framed shed. There's a little covered porch at the door end that adds 4' more to the 24' length. I'll post a pic or two soon. two $9 rods isn't much.

Actually, I did use 1", but didn't run it the whole way. It's what the 12/3 UF is in above 24" below grade at both ends. (I decided to not try pulling it through 3/4".) I intend to pull the GEC through the same sleeve at the shed end.

I see no reason that 1 inch could not protect both the 12-3 and the ground.