My pump motor is wired for 220 [done by previous owner] with 12 gauge 2 wire i.e. black/white/green. The black and white are both hot and there is no neutral.
I would like to wire a nearby receptacle for 110. I can use one hot leg and the ground, but where/what do I use for a neutral?
Thanks.
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Replies
You're screwed. Run the right cable and start over. You should also have that 120 receptacle on a separate breaker from the 240 circuit.
Indeed, since you'll now have more than one circuit, other requirements may also apply. Hiring an electrician might be a good idea.
Thanks for the rapid reply. Kind of what I thought. Luckily the panel is close by.I just had the electricians out here a few months ago to run power to my garage. Too bad I didn't pick up on this then.
As there seems to be a bit of confusion, let me explain my answer a bit more.
The NEC requires 'detached structures' with more than one branch circuit to have a ground rod. think "separate building = separate lightning target.'
Clarified in the 2008 NEC, this ground rod does NOT remove the need for a ground wire connecting it all to the ground buss at the source ..... you are also still required to have a separate neutral wire, and to keep the neutrals and grounds separate from each other until you get back to where the power company disconnect is.
This situation arises whether you get your 120 from the same breaker that feeds the 240 pump, or if you run a separate cable.
That's why I always tell folks .... run big pipe; some day you might want more or bigger wires out there. Such planning saves you from digging a second time. As you might guess, such advice is almost always met with "but I'm only running a pump, and I'll never want anything else out there." Then the pump guy arrives, and needs 120 for his tools. Oh, well.
The size of the feeder cable (the wire currently powering the pump) might not be an issue. It might have been possible to supply both the pump and the receptacle using that cable (the electrician does some load calcs to determine this) ... but you're still lacking that necessary neutral.
Again, in my work there are time where I always run a neutral, even if I have no present need for one; this is one of those times.
I recently had to deliver the same sort of bad news to a customer: he went to such great pains three years ago to do something in the absolute cheapest way possible - even cutting a few corners - that today even a minor change leads to major expense.
While there might be some way to 'hillbilly' in something that 'works,' you're still left with an inadequate situation. You just postponing judgement day a bit.
I do NOT aim this post at the OP personally ..... long time BT readers know just the sort of person I refer to. For them, I want to say 'no, you can't do it - and they can't help.'
Thanks to all that replied. When I had my garage powered up they had to replace my CB panel which is outdoors within three feet of my pump motor. Too bad then I didn't look ahead. I didn't try to do it on the cheap, I just didn't know any better and didn't anticipate what else I might need.If I had wanted to do it cheap I would have run NM under my trailer and only then buried it going to the garage.Off the original topic, I've put more into this 1985 single wide divorce trophy club house than its original worth. Front and back porch with Trex. New carpet throughout. New kitchen cabs and countertops. Total bathroom demo and remodel with cork floors and granite countertop vanity. My son says it's like putting a tuxedo on a pig, but I don't want to build another house with a mortgage that will last the rest of my life.
not an electrician but I've done this a few times
you need 3 conductors (2 hot, 1 neutral) and a ground run from the main panel to a sub-panel at the pump. Sub-panel should have it's own ground rod. At the sub-panel install appropriately sized CBs to handle the pump and the 110v outlet you want to run. receptacle ought to be GFCI.
Huh?
You suggest:
1) New heavier home run to main panel with new breaker.
2) New sub-panel with breakers (possibly reuse old pump breaker in new sub panel, brand / listing issue)
3) New ground rod (not needed if sub-panel is in the same building)
4) New cable run from sub-panel to pump.
5) New cable run from sub-panel to new outlet; requires a new breaker in the sub-panel.
6) Possible GFCI protection for the new outlet.
What he needs:
1) New cable run from outlet to main panel; requires new breaker in main panel.
2) Possible GFCI protection for new outlet.
Why do / pay for steps #1 through #4?????
Jim
Never underestimate the value of a sharp pencil or good light.
under the impression it's run out to a remote location.
didn't think about a separate new 110v feed.
I suspect this is a submersible pump in the well.
Hint was in the OP, "12 ga, black, white, green" the hint was the "green" rather than "bare".
Sounds like that submersible pump wire (don't know the proper name).
My assumption is a submersible well pump and that the outlet in question is in his basement.
'Course we all know what they say about assuming..........
OP does not suffer from TMI.
JimNever underestimate the value of a sharp pencil or good light.
I was assuming (also) wellhouse like we use here where long frosts are not an issue (at least they weren't in the past) and he was looking for a way to add soemthing to add heat during the frosts. The well house usually includes the pressure switch and pressure tank and a sediment filter. Many cases original install is done as cheap as possible with only power feeding the pump and no sub panel and the desire to add heat later. Come to think of it, it's been so long since I've been involved with the no-sub panel set-up I don't remember what they used for a service disconnect at the well head.
cheers
john
The pump is legally wired as it sits right now. No neutral is required for a pure 240v load --- if you were to run a cable with a neutral conductor to supply the pump motor, there would not be anywhere to connect it at the pump motor. 2 hots and a frame ground is all there is.
You simply need to run a new 120v cable to the new outlet, a new single pole breaker will be required at the main panel.
The new sub-panel, suggested by another poster, will work properly at a greatly increased expense over what you actually need.
The sub-panel is a good solution only if you are out of space in the main panel and tandem or skinny breakers will not work in your main panel. If the sub-panel is in the same building as the main panel, no additional ground rods are required.
If you are out of space in the main panel, I would tend to run a new sub-panel with 8 to 12 slots available rather than just a small panel to accommodate your present needs. Probably a 60 or 100 amp sub panel
GFCI protection is required for the new outlet if it is outside or in a basement.
Jim
You don't.