Wiring to & within workshed


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Old 10-18-10, 09:08 PM
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Wiring to & within workshed

I want to run electric to my 15 x 20 detached workshed.
Two 20 amp circuits should suffice: one for lighting, the other for outlets.
The feed will come from my house breaker panel via underground PVC.
Should I use 8 or 10 ga wire?
Common neutral -or two seperate neutrals?
Ground rod at the shed -or ground wire from the house breaker?
I want to use a main disconnect switch before a two position breaker box.
Since GFI breakers arer very expensive, can I just use outlet GFI's in series?
Does the lighting circuit need GFI protection?
Many thanks!
Bill
 
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Old 10-18-10, 09:36 PM
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Sounds like you would be set with a 20A multiwire circuit (hot-hot-neutral-ground). Wire size should be #12 up to about 100', upsize to #10 if it's longer distance. Your conduit should be 18" deep. No breaker panel or ground rod is required at the shed. A disconnect is required, but that can be as simple as a double-pole switch or air conditioner disconnect. The breaker in the main panel should be handle tied. You can use two GFCI receptacles after the shared neutral circuit splits into two circuits inside the shed. The lights do not require GFCI if they are hardwired, but do require GFCI if they plug in.
 
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Old 10-18-10, 09:38 PM
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If you only want two 120v circuits and assuming the distance is less then 100 feet you can use a multiwire circuit. Two#12 hots, one #12 neutral and one #12 ground from a 240v 20a breaker in the main panel. You do not need a panel at the shed, just a DPST switch in a 4X4 box or a 30a unfused disconnect switch. Yes, you can use GFCI receptacles.

Dang, Ben types faster then I do.
 

Last edited by ray2047; 10-18-10 at 10:56 PM.
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Old 10-18-10, 10:15 PM
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If you going to use the PVC conduit I will suggest to leave it larger like 1 inch size due in down the road you may want to put it larger conductors in case the loads get hevier or you have 240 volts equiment then you have to go this route anyway.

So just give you a head up before you start digging up the ground and lay the conduit and and short time later you have to change the whole thing so it will be wise to spend little more for larger conduit and be done with it and you always can snake in new larger conductor as need to.

I done like that few time and quite few case it did result to change to larger condutors it did save alot of the time there.

Merci.
Marc
 
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Old 10-19-10, 05:57 AM
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Many thanks!

Many thanks for the guidance with this project.
Will run 1" PVC 18 " underground -also an additional 1/2" PVC for low-voltage (telephone & speakers)
Will use multiwire to quick-disconnect box
GFI outlets in series
No GFI on hard-wired lamps
Beer and chips -upon completion.
Bill
 
  #6  
Old 10-19-10, 08:05 AM
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Originally Posted by Bill Mozer View Post
GFI outlets in series
Not exactly in series. At the first box right after the disconnect should be a double gang with two GFCI receptacles. You should have hot, hot, neutral, ground coming in. The neutral will get two pigtails wirenutted on. GFCI #1 gets the first hot and one of the neutral pigtails on its LINE terminals. GFCI #2 gets the other hot and the other neutral on its LINE terminals. Both recepts and the box get a ground pigtail.

Now you have both a hot and neutral terminal open on the LOAD side of each GFCI. From this point on you basically treat them like separate circuits; the neutral is not shared after this point. Carry on with two runs of 12/2 from here.**

No GFI on hard-wired lamps
It's optional, but it can't really hurt to provide it.

Beer and chips -upon completion.
This part I fully endorse.

** Some jurisdictions allow 12/2 "Romex" exposed in a workshed, but some do not. You might need conduit or a more durable wiring method like armored cable (BX) or metal cable (MC) if the wiring is exposed and the job will be inspected. If the wiring will be protected in the walls by interior sheathing (drywall, OSB, etc) then Romex should be okay.
 
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Old 10-19-10, 08:48 AM
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Just a suggestion.

If you are going to this much trouble you may have more flexibility by running a #10-3 conductor (plus ground) on a 30 amp two pole breaker and install a sub-panel in the garage.
You then would have the possibility of running a small 220 volt mig welder or air compressor.
 
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Old 10-19-10, 10:38 AM
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A ground rod would then be needed
 
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Old 10-19-10, 01:13 PM
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Where I am a ground rod is not required.
You need to separate the ground/neutral bonding strap and have the house wiring carry the ground.

There are folks here that can elaborate further.
 
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Old 10-19-10, 04:36 PM
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hmm thought the poster was posting from the U.S.
 
 

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