HI, I just built an 8x12 shed over my well. The well had an existing A frame
cover over it. It is 5' x 4' x5'2" deep. Has a jet pump wired straight from
main panel at electric pole, 3 wires directly wired to pressure switch. 220 ,
Here's the question, is there any way to use the exisisting wiring to supply
110 power to shed? All I'm looking at is a couple of lights, a couple of
plugs for minor tool usage.
By "3 wires" you mean two hots and a ground? Then no, you can't do it
Running a neutral wire would, if nothing perverse ever happens, be safe; but
since code watches out for perverse happenings, it wouldn't be legal.
You might want to check the voltage to be sure. My pump is 120v. Shouldn't
be; the voltage drop is murder, but it is.
You could wire up 240v lights, but that wouldn't help you with the tool
And before you do anything; make sure you have adequate capacity to add
lights. If you are marginal now, the pump won't like sharing.
Thanks, I'm positive that the pump is 220. Here's the story, the orignal
structure on the property burned to the ground 5 years ago. At the time, the
well was wired into the breaker box in the house. When the house went, all
power to the well went, no water to fight the fire. So when I had the
doublewide set up, I had a friend run the electric straight from the box on
the pole to the well. The breaker box has a double pull dedicated to that
wire alone. I know the pump at one time was set up for 120 but was switched
over when contruction was final. Like an idiot, I let a friend run the wire,
thinking he knew what he was doing, I was wrong. So what I now have is a
cable with 3 wires buried under the ground to the well, what I want is to be
able to put a sub-panel into the shed above the well for lights and outlets.
How can I best accomplish this without burying more wire.
Personally I wouldn't do this, but until the 20 years ago 240v applicance
were allowed to put their unbalanced load from 120v uses back over the
uninsulated neutral. In fact, the top element on my lower oven puts 10a
back over the neutral. That is probably more than you would get from a few
Is it safe? I have never heard of anyone getting hurt on the millions of
such installations like that out there; but there is the potential for a
problem. Probably safer than driving to the market, but since it is
illegal... It is one thing to leave my 24 year old wiring in place; it is
quite another to install another one.
I am posting this mainly to get Dougie upset.
Multiple code and safety violations:
- The existing ground conductor is almost certainly uninsulated and therefore
unsuitable for use as a neutral.
- The ground conductor at the shed would not be tied to the service entrance
ground and could therefore be at a different potential. Google on "ground
loop" for information regarding the dangers.
- This cannot be alleviated by running a separate conductor, either, as the
Code requires that all circuit conductors be contained within the same cable
The only safe and Code-compliant option I can see for the OP is to convert the
circuit back to 120V to provide neutral and ground for the lights and outlets
he wants, and either use a step-up transformer to provide 240V for the pump,
or convert the pump back to 120V as he says it was originally.
Doug Miller (alphageek at milmac dot com)
Around here (Saskatchewan) separate buildings are allowed to have their
own ground rods and a ground line is not required to be brought with the
feeders (although it is allowed to omit the ground rod and bring ground
in with the feeder lines, as long as the building doesn't house livestock).
Looking at the online 2005 NEC, 250.32 B(2) seems to discuss this case,
in that it describes what to do with the "grounded conductor" when a
"grounding conductor" is not brought along with the supply. Am I
missing something here?
Hang on, before you guys get all upset, from what I can tell, what he buried
was romex. Nothing fancy or special. And it's not the first time this guy
has acted like he knew what he was doing, I've had him mess up an older
motorhome I was remodeling as well, I wound up re doing that, not to mention
a few other things. I'm not blaming him, I just should have known better and
tried to do it myself. And for the books, I'm a 53 year old female. I often
don't know the correct name for things, but I'm not afraid to try. I've
changed the alternator in my car, it involved lowering the cardle and pulling
a tie rod end, I've built a deck that is 10sf less than my house, remodeled a
bath, installing a large garden tub, and last but not least, I put in a
french door from my bedroom out onto the deck. So, Please, I'm willing to
learn, teach me.
Chris Friesen wrote:
Message posted via HomeKB.com
If it was romex, then you really should pull it out and have it redone
properly. Romex is neither permitted, nor safe, for underground use. You need
Type UF (Underground Feeder) cable for this application.
OK, well -- you need a 4-wire UF cable, sized to the total load, and an
appropriate double-pole circuit breaker. Or bury a conduit, and pull four THHN
or THWN wires of the appropriate size.
One way or another, you need four wires.
Doug Miller (alphageek at milmac dot com)
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