RURAL LOCATION REQUIRING WELL PUMPS

[champion]

Anyone out there that can direct me to code information regarding branch ckt, grounding and disconnect information about well pumps powered via the AC service in a dwelling unit.
Well escavator indicated the pump used is a 2 hp 240v 12.0 amp motor. 33.0 starting amps.

 

[drg]

Re: RURAL LOCATION REQUIRING WELL PUMPS

Champion, I do not understand "well pump powered thru the AC service"...can you explain more on that.

John

I always see the pump hooked direct at the pressure switch on #12Cu and the 20 amp breaker in the panel is the disconnect for this type of system.

[ February 26, 2004, 07:30 PM: Message edited by: drg ]

 

[tom baker]

Re: RURAL LOCATION REQUIRING WELL PUMPS

Motor rules are in Article 430 of the NEC.
Will the ciruit to the well building be a feeder or branch circuit?
A feeder requires a disconnecting means and grounding electrodes at the well building
A branch circuit requires no disconnect but still need grounding electodes.
For a 2 hp 240 Volt well motor my Square D motor data calculator shows 10 AWG, 50 TM QO type CB, of course the wire size depends on the distance.
Most pump mfgs have tables showing wire size and distance.

 

[pierre]

Re: RURAL LOCATION REQUIRING WELL PUMPS

Tom
Where did you find the requirement for a grounding electrode for branch circuit at a well house?

Pierre

 

[bennie]

Re: RURAL LOCATION REQUIRING WELL PUMPS

On a farm, the only water supply to combat a fire is the well pump. The feeder to the pump must be independant of the service main.

I would run a set of service entrance conductors from the supply side of the service drop or laterial, to the pump house. Use the well casing for a service ground at the well.

 

[iwire]

Re: RURAL LOCATION REQUIRING WELL PUMPS

BENNIE

 

[bennie]

Re: RURAL LOCATION REQUIRING WELL PUMPS

Bob: I am back for a short time. I am planning for lung surgery at the University of Washington Medical Center, in the near future.

In case I do not survive the surgery, I may as well go down in flames

 

[tom baker]

Re: RURAL LOCATION REQUIRING WELL PUMPS

Very polite, Pierre. Right, a branch circuit does not require a grounding electrode system.
And in Washington State, a well casing is considered a water pipe and requires ground rods to supplement. I have installed two ground rods next to a 400 foot deep 16" dia well casing.
I once installed a service at a dam, 500 feet across and 125 feet high, a concrete gravity type, I bonded to the outlet pipe and had to install ground rods. Code is Code.

 

[tom baker]

Re: RURAL LOCATION REQUIRING WELL PUMPS

Some locations treat the submersible water well pump as a fire pump source, by the fire marshall. Its not exactly an Art 690 application, but Bennies method is suitable.

 

[iwire]

Re: RURAL LOCATION REQUIRING WELL PUMPS

Originally posted by bennie:
Bob: I am back for a short time. I am planning for lung surgery at the University of Washington Medical Center, in the near future.

In case I do not survive the surgery, I may as well go down in flames

You know you have the well wishes of many of us here.

Bob

 

[champion]

Re: RURAL LOCATION REQUIRING WELL PUMPS

This is Champion and I am sorry I did not give all the information regarding the well pump.
The location for the well pump will be used as the water supply for a dwelling unit.
I'am not concerned about voltage drop mainly because I have computed this already but the pump will be controlled through a preasue switch at the location of the accumilator near the water heater etc.
I was basically concerned about computing the power requirements for the pump because I could not find anything directly for this application in the code book.
I can assume I should treat it as a motor ckt and use the information found in article 430.
I am really not sure.
Again the motor which will be located approximately 240ft deep is a 240v 12.0 amp motor.
Sorry for the confusion.

 

[bennie]

Re: RURAL LOCATION REQUIRING WELL PUMPS

My calculations are; 483 feet of 10 gauge wire with 12 amps will create a voltage drop of 14.4 volts. This provides 229 volts at the motor terminals.

The same length of 12 gauge will have a drop of 23 volts. This will be 217 volts at the terminals, which is under the rating of the motor.

You need to supply the exact length of the entire circuit for an exact calculation.

A pump motor is a motor circuit

[ February 26, 2004, 11:18 PM: Message edited by: bennie ]

 

[drg]

Re: RURAL LOCATION REQUIRING WELL PUMPS

Champion, I do not think they put the pump/motor down 240ft.
I would imagine that the pump would draw (lift) from close to the surface and work from there.......... with a vertical check valve beneath the pump its self.

John

 

[tonyi]

Re: RURAL LOCATION REQUIRING WELL PUMPS

Depends on the well. Some places in upstate NY have very deep wells to get past a shale ledge (go above that and you'll go dry in the summer). 500'+ is not uncommon in the town I grew up in.

 

[drg]

Re: RURAL LOCATION REQUIRING WELL PUMPS

500ft or a 1000ft ....either way they are going to use suction to do this , and the pump/motor is at the first 10 ft or so below grade not at the point.

John

 

[iwire]

Re: RURAL LOCATION REQUIRING WELL PUMPS

500ft or a 1000ft ....either way they are going to use suction to do this , and the pump/motor is at the first 10 ft or so below grade not at the point.

John

John the pumps are down the hole, you can not lift water that far with suction.

At sea level you can only lift water about 26 feet.

You have to remember that you really do not suction the water, atmospheric pressure pushes the water up when the air is removed from the pipe.

All the pumps here are submersibles.

[ February 27, 2004, 05:35 AM: Message edited by: iwire ]

 

[drg]

Re: RURAL LOCATION REQUIRING WELL PUMPS

Guess was told sometime a time or 2 and believed just what I said, now feel like a dope....

If there is one thing I am going to learn around here is to quit being so pigheaded and discount just about everything anyone tells me anymore .....

Use to get told incorrect information at work all the time and believed it ......now I have resourses
to find the facts.....when i find that have been told something wrong i will probaly not say anything to the person....don't like to be confrontive and a lot of people have a problem
being told that they are wrong.......even when using diplomatic means some people freakout......then I start laughing and that makes things worst...

Appreciate the pump pictures Bob, and your explanation....

Wished I never made that post last night but now at least there was something learned here today and has me rethinking about alot of other stuff, time to retool my learning methods and thought process.


JohNCOnfuseDanDEmbarrAsSed

 

[champion]

Re: RURAL LOCATION REQUIRING WELL PUMPS

The well digger indicated to me that at least in the county where this dwelling unit resides they drill the well and as they drill the well using special bits of some kind which I will watch as the well is dug, the hole is encased as they dig.
The pump motor is located(at least in this county) always 40 feet above the water depth. The deeper the well in most cases the cleaner the water. The encasement, or water pipe highway from the pump does have a check valve to eliminate or minimize preasure loss when the pump is not running.
Someone mentioned a grd electrode would be required for this pump and that no disconnect would be required and I am assuming by reading parts of article 430 that the preasure switch (controller) bay be acting as required disconnect in this case.
I will read more on article 250 and 430 for disconnect and grd electrode information to try and clear up any confusion that I may be having. Thank you all for responding, and if anyone has any further comments on this they most certainly will be welcomed.
Thank you

 

[bennie]

Re: RURAL LOCATION REQUIRING WELL PUMPS

If this were my well pump, I would run an unfused service feeder to the well house and terminate it in a four circuit panel. I would install a two pole breaker for the pump, and whatever the heat cable may require. A light may also be necessary.

 

[iwire]

Re: RURAL LOCATION REQUIRING WELL PUMPS

Originally posted by drg:
Appreciate the pump pictures Bob, and your explanation....

John, I had some help, Dad was a plumber.

And this place will teach you quick to check your facts, there a lot of sharp people here.

I have stuck my foot in my mouth more than a time or two here