square D pump switch ?

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greybeard

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I want to tap off one 120v leg of my water well wiring to put in a 120v receptacle at the water well pressure switch.
My water well is a sub pump, running off 240v single ph.
Powered by 2 lines of 120v each and one ground wire brought in via conduit. There was no neutral wire run.
The power is supplied off a disconnect on the side of my house, which is fed directly from a breaker in the main panel of my house--the main is 'first means of disconnect' which means neutral and ground bus are tied together per code in that main dist panel.
Water well switch is wired just like the one below:




(All I want to run off the receptacle is a 100W light bulb)
If I tap off from locations A & B, (from 1 hot and the ground lug) it will give me 120V ac, but will this be safe?
 
greybeard":3051trel said:
....(All I want to run off the receptacle is a 100W light bulb)
If I tap off from locations A & B, (from 1 hot and the ground lug) it will give me 120V ac, but will this be safe?


Understand whatcha wanna do, but sorry, definitely not safe.....
Seems everyone, myself included, would really like to have a light and/or receptacle by the well pump switch, yet its rarely designed into most electrical plans.
 
It works, I run my catch pen off the well pump switch. Come to think about it I also have my fence charger running off the pump switch, maybe that's why it works so good. IDK
:hide:
 
Yes, I know it will 'work', and I fully understand the difference between neutral and ground. In basic terms, electricity comes to our house (and equipment circuits) all voltage no current and 'leaves' all current no voltage..or is supposed to anyway and that's the danger. It only takes a small measure of voltage present on a neutral line to be deadly, which is one of the reasons most of our residential transformers have the neutral grounded down the bottom of the pole under ground..to keep something in the house from sending stray voltage back down the neutral line where a linesman could get zapped. I've argued the same point several times, that both a neutral and ground MUST be there in 120V circuits and many 240v circuits and NEC requires it. All it takes in any circuit is to lose neutral and the grounding prong 'may' become 'hot'. IF my well tubing and casing was steel pipe and not PVC, I'd be less concerned but it isn't.

But, having said that, isn't it true that with AC, that every ground circuit in the house is already also neutral since neutral and ground are bonded together at the first means of disconnect?
 
Maybe to be on the safe side you need to buy a breaker box with a breaker for the well and another 110 volt breaker for the light and outlet. Should not cost that much. Probable less than $50. I assume that you have it in a well house.
 
hurleyjd":3s63u4x2 said:
Maybe to be on the safe side you need to buy a breaker box with a breaker for the well and another 110 volt breaker for the light and outlet. Should not cost that much. Probable less than $50. I assume that you have it in a well house.

A breaker doesn't have anything to do with it. They are there just to protect the wiring and it's insulation. By the time the 30a breaker senses 30a and trips, I would already be dead.
A 110v single pole GCFI outlet for the light would work better IF there was a neutral, and there are 240v 2 pole GCFIs that would be fine at the disconnect location IF I wasn't adding an outlet to one side of the 240v circuit down line.
GCFIs work by looking for imbalance and since one side, when the light was on, would be different, it's likely the GCFI would trip as soon as both the well pump was running and the light was turned on.

Odds are very very good that I would never have a problem just connecting in a pigtail as I had originally asked about, but I'm pretty cautious about getting zapped....

Also...Cottage Farm:
What effect (if any) would the 100watt bulb have on the pump motor in relation to both legs of the windings needing to be in voltage balance? Is it such a small draw as to make no difference?
 
greybeard":1xwfxmwv said:
Odds are very very good that I would never have a problem just connecting in a pigtail as I had originally asked about, but I'm pretty cautious about getting zapped....

From what you described, doesn't sound like you would have a problem. The safety concern is that entire ground leg that runs back to your panel (from the pump)has the potential for zapping...and any other ground wires that are also connected to it before it gets back to the service panel..based on what was posted by several in the link i posted.
 
You could buy a small transformer and safely do what you are wanting to do. It would generate its own neutral from the 240 volt. They use them in rooftop AC units so there is power for the service tech.
 
greybeard":1izxre1w said:
hurleyjd":1izxre1w said:
Maybe to be on the safe side you need to buy a breaker box with a breaker for the well and another 110 volt breaker for the light and outlet. Should not cost that much. Probable less than $50. I assume that you have it in a well house.

A breaker doesn't have anything to do with it. They are there just to protect the wiring and it's insulation. By the time the 30a breaker senses 30a and trips, I would already be dead.
A 110v single pole GCFI outlet for the light would work better IF there was a neutral, and there are 240v 2 pole GCFIs that would be fine at the disconnect location IF I wasn't adding an outlet to one side of the 240v circuit down line.
GCFIs work by looking for imbalance and since one side, when the light was on, would be different, it's likely the GCFI would trip as soon as both the well pump was running and the light was turned on.

Odds are very very good that I would never have a problem just connecting in a pigtail as I had originally asked about, but I'm pretty cautious about getting zapped....

Also...Cottage Farm:
What effect (if any) would the 100watt bulb have on the pump motor in relation to both legs of the windings needing to be in voltage balance? Is it such a small draw as to make no difference?

I think he's talking about installing a box then split the well pump and light from the box. We did that when we wired papaws barn. Pulled from either a 30 or 50 (can't remember) inside the main house box. Ran a wire underground to another box in the barn. And had a couple breakers from there to wire lights and outlets
 
greybeard":1xn7co69 said:
hurleyjd":1xn7co69 said:
Maybe to be on the safe side you need to buy a breaker box with a breaker for the well and another 110 volt breaker for the light and outlet. Should not cost that much. Probable less than $50. I assume that you have it in a well house.

A breaker doesn't have anything to do with it. They are there just to protect the wiring and it's insulation. By the time the 30a breaker senses 30a and trips, I would already be dead.
A 110v single pole GCFI outlet for the light would work better IF there was a neutral, and there are 240v 2 pole GCFIs that would be fine at the disconnect location IF I wasn't adding an outlet to one side of the 240v circuit down line.
GCFIs work by looking for imbalance and since one side, when the light was on, would be different, it's likely the GCFI would trip as soon as both the well pump was running and the light was turned on.

Odds are very very good that I would never have a problem just connecting in a pigtail as I had originally asked about, but I'm pretty cautious about getting zapped....

Also...Cottage Farm:
What effect (if any) would the 100watt bulb have on the pump motor in relation to both legs of the windings needing to be in voltage balance? Is it such a small draw as to make no difference?

If you split your pigtail off upstream of the pump switch, it probably wouldn't draw enough to be an issue(dont know your amps/in vs. amps/out...that said you know this isn't a good idea :lol:

If the situation were mine again, I would get a 100w solar panel for $100 (maybe they're less now?) and use an LED light that will give you the equivalent of 100w incandescent but only use about 20w. Safe and fairly cheap.
 
A LED light won't put off enough heat to keep the switch from freezing. I don't know if he's trying to accomplish that or not, I just thought I throw that out there.
 
True Grit Farms":1inqmhok said:
A LED light won't put off enough heat to keep the switch from freezing. I don't know if he's trying to accomplish that or not, I just thought I throw that out there.
yep, that's my goal.
No more often than we get a hard freeze, I don't really want to go to a lot of trouble or expense, but I've tried insulating the heck out of it and it doesn't work. Nipple to the switch freezes most times..sometimes cracks.
Other times, the water under the diaphragm freezes and if it happens to do it while the pump is running, it just keeps running till tank pressure builds up and blows the relief valve. :(

I'm tired of running an extension cord out there just to run a lamp under a bucket above the pressure switch.
 

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