New Well Pump wiring

Randell Tarin

We have just had a new well drilled. The wiring requirements given by the pump installer were a two-pole 30 amp breaker, and since it's about 200 ft. from the main panel, we've upped the conductor to #8-2 UF with ground. This is, I'm guessing fine for a direct 220v connection (two hots and a ground).

However, I will be building a well house around the pump and tank and have considered installing a small subpanel to add single 110v circuit for a light and pipe heater.

My question is this: Since the grounding bar for the sub-panel will be isolated from the neutral bar can I use the bare copper ground from the main panel as the neutral since the grounding bar will be bonded to a grounding rod at the subpanel? I would probably wrap the bare ground with insulating tape so it would not make contact with the subpanel box.

8-2 UF is about half the price of 8-3 UF...I'd like to save money, but I dont' want to be stupid about it.

McSteve

No dice. The only safe and legal way to have 120V at the pump house is with the 8-3 UF.

jbfan

I bet conduit and individual wires will be cheaper than uf, or at least equal and allow options for the future.

Oh yea, what the mad scientist said about needing the 3 cond. and ground.

__________________
Yes I am a Pirate, 200 years too late. "Jimmy Buffett"

wirenut1110

Ditto.

stickboy1375

What is the HP of the pump?

#8 AWG with a 1/2 HP pump can be used up to 1610' with proper voltage drop...

7 1/2 HP pump maxes out at 200' with # 8AWG., just to give you a little perspective on your wire selection choice.

__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

stickboy1375

I dont think I would let a well pump installer tell me how to size the breaker or wire...

__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Randell Tarin

It's a 2 HP pump.

Randell Tarin

So, if I already have the 8-2 UF and am going to run it in conduit, I could use a single #8 wire run in the same conduit as my neutral?

stickboy1375

#12 AWG is good for 250', but were talking from service entrance to the actual well pump.

__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

stickboy1375

So if you did this, would the light only turn on when the well was running? What i'm asking is, where are the pump controls located? At the pump house?

__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Randell Tarin

They'll be attached to the wall of the well house, I'm guessing.

I'm talking about a separate 110v circuit off of a subpanel. I have the wiring for the pump (to be installed next week) It will be laying on top of the ground until I get my plumber in here to trench and connect the well to my plumbing. I'm going to then place the electrical conduit with the requisite wire in the same trench.

I was just wondering if I could use the bare ground for the neutral since it would not be bonded to the ground at the subpanel. Obviously, it will need to be insulated to keep it from touching the sides of the box enclosure. I thought maybe I could have a section of insulated #10 wire pig-tailed to the ground in a non-conductive junction box outside of the subpanel. Then have the insulated wire entering the subpanel attached to the isolated neutral bar. The other end of the bare ground is going to the grounding/neutral bar in the main panel where both grounds and neutrals terminate anyway.

Randell Tarin

#12 isn't rated for 30 amp is it?

stickboy1375

Thats not how it works, the pump itself contains the overload protection, the 30 amp breaker is only for ground fault and short circuit protection.

__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

stickboy1375

Absolutely NOT!



No... you need to buy the correct wire for the job.... Personally, I would just buy some 12-2 UF at this point, and use it for the light, of course, now you have a structure and other violations will follow. So really, the thing to do is go buy some XX-3 UF wire.

__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Randell Tarin

[QUOTE=stickboy1375;979980]Absolutely NOT!


I don't understand why.

The ground will not be coming from the main panel. It will be attached to the grounding bar in the subpanel that is grounded by a separate grounding rod at the subpanel. The two panels will not be metallically bonded.

The wire running from the main panel would be isolated and insulated from the sub-panel box on the neutral bar. It is attached at the main panel to the common/neutral ground bar.

How is this any different from having a separate neutral running from the main panel? If the bare ground is pig-tailed to an insulated section of #10 wire at both ends, then why could it not serve as the neutral? It's insulated from beginning to end.

As long as the neutral and ground are isolated at the sub-panel, I can't see how this is any different than running 8-3 w/ ground to the subpanel since the ground is going to be essentially unused.