Submersible deep well pump

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  #1  
Old 09-16-00, 10:18 PM
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Installed submersible pump at depth of 380'. Used 10/3 (3 wire pump). 10/3 runs from well pump to pump control box. Ran 12/2 from control box (only had 2 wire connections and ground) to disconnect switch (also 2 wire/ground) and 12/2 from disconnect to 30 amp, 2 pole breaker in service panel. Pump will not work. What did we do wrong? How do we fix it? Any help will be appreciated.
 
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  #2  
Old 09-16-00, 11:09 PM
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I'm not an electrician, and I don't know exactly how you wired this up, but I guess that you know that the white wire in the 12/2 is supposed to be hot (no neutral, if this is a 220-v pump.) Did you make sure that the pump itself is set for 220v, and not 110v, if that what it is supposed to be? If 220v, did you connect the 12/2 white through to the 10/3 red? Black to black? Ground to ground? If you can give a little more info, I am sure that one of the pro electricians in here can help you. Good Luck!
 
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Old 09-17-00, 06:49 AM
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Pump motor is wired to black/yellow/red in control box. 12/2 is wired white to L1 and black to L2 (The only connections leaving the control box). These go to disconnect box, white to L1, black to L2. At service panel, have 30 amp 2 pole breaker. White and black are wired into poles on the breaker. Pump is 1 1/2 HP, 3 wire, 220 v. We also have a pump saver and pressure switch but they are not wired up yet, we are initializing the pump as per instructions, or at least we are trying to. There could be other problems, but am trying to rule out the easiest first. Please help.
 
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Old 09-17-00, 08:21 AM
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It sounds like the wiring is ok per your description. Have you checked to see if you are getting voltage at the disconnect switch and at the pump control box. Its possible that the control box contacts were not making good contact. The covers can be tricky to put back on sometimes.

I suspect the problem is in the controller.

If you have voltage at the control box the problem can be one of three things; 1. The control box is bad or not making good contact, 2. The splice at the pump is bad (not a good thing) or 3. The pump is bad (even worse than no.2).

If you can verify that you are getting power out of the control box and the pump still won't run, your only option is to pull the pump and check the wiring connections at the pump. If they are good, the pump is the problem.

I hope you don't have to pull the pump. I had to pull one setting 330 ft. down recently and we set a A-frame over the well head. We tied a rope to the well head and the other end to the bumper of a truck. Pulled it in 15 minutes.
 
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Old 09-17-00, 10:18 AM
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Well I may have some bad news for you. You may need to redesign the project.

Now I am taking some info as estimates but should be close.

You said that you have a deep well 240 volt pump, 380' deep, unknown distance from the control box to the pump, unknown distance from the control box to the panel, unknown distance from the panel to the Utility company's transformer.

Just say we plug in a distance from the transformer to the pump motor as follows;

380' deep + 250' from the top of the well through the control box through to the panel and through to the Utility company's transformer.

If we plugged in this distance as a guess the following is a guesstimate of your problem.

You said that you ran 10ga on part of the ciruit, then 12 ga on a part of the circuit then back to 10 ga on the other part of the circuit. You can only size a circuit by the smallest conductor on that circuit. Your breaker size should have been limited to a twenty amp breaker by normal means.

If we sized the branch circuit with no voltage drop considered then the conductor's minimum size should be approximately 13 amp rated, the overload should be size approximately 13 amps, the overcurrent device could be sized up to a maximum of 25 amps. This is as per Chapter 4 of the NEC

I don't see you that far off this except that you stuck the 12 ga. in the middle of the circuit which would severly affect a voltage drop on this circuit.

At the very least you should change the 12 ga to 10 ga from start to end of this circuit. The 30 amp breaker should be ok.

Now if we used the distance between the Utility company's transformer and the bottom of the well where the pump is the following most likely will be you problem.


1 1/2 hp motor at full load current pulls 10 amps at 240 volt as the voltage goes down the amperage will exceed the rated full load current of the motor.

If you entered 730' from the transformer to the motor at the bottom of the well then you should experience the following;

Approximately 11% voltage drop or 28.17 volts lost, with the 12 ga wiring in the circuit at an end of line voltage of approximately 201 volts with a supply voltage of 230 volts

Approximately 8% voltage drop or 18.22 volts lost, with the circuit entirly 10 ga. wiring at an end of line voltage of approximately 211 volts with a supply voltage of 230 volts.

You may not have enough electricity for the pump motor to run lifting the water that much distance and then transporting the water to the house and through the house plumbing to the faucet.

I suggest moving the control box next to the well casing protected from weather, keeping the breaker size the same, increasing the wiring size from the breaker to the pump motor to 6 ga. to obsorb the voltage drop then increasing the size water line from the pump to the house to a 1 1/2 pipe to reduce resistance in the water pipes.

Hope this gives you some ideas to look at

Wg

This should give you the best shot to make it work.
 
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Old 09-17-00, 10:29 AM
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I forgot to mention the voltage drop tolerance acceptable in the electrical industry.

The Fire Protection Note in the NEC states that 5% is considered acceptable for wiring design in the electrical industry.

If you Utility company has you at the far end of their lines the voltage could drop as low as 200 volts and meet the requirements to the Utility Regulatory Commission. Now add the possibility that you have a main service panel too small to meet the damand load of your dwelling, and a possible voltage drop as suggested in my previous reply. You could have any of all of these problems.

I suspect that your motor is starving for enough electricity to start and run the pump motor.

Something to look at.

Wg
 
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Old 09-17-00, 02:02 PM
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Hi...I looked at your problem ,and with the well experience that i have, i think old R.L. has probably hit the nail on the head, not that you don't have a voltage drop off, which you can check with a voltage meter. My guess that either your starting capactior is bad, you are not getting a connection when you put your box together, or you have a bad connection where you connected your pump wires to your wires coming out of well,or you have a faulty pump. Wish i could give you better news, but try your control box first, then work from there...Good Luck..Charlie..
 
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Old 09-17-00, 04:53 PM
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I definetly agree with at least 8 AWG wire if not 6AWG. Leave the controoler inside since this is where you have it. It will not make any difference wheather it is inside or out.
A MAJOR RECOMENDATION:
Pull the pump up if there is not a connecton problem at the controller or well casing top. Having a well that we had many problems with 6 years ago, I know what a hassle this is.
Connect the motor directly to the controller with a short piece of 10 AWG wire just to see that the motor functions properly. THis way there are no surprises once you put the pump back down the entire 380 ft. The problems we had were either the wires were deteriorated, the capacitor or relay were bad, or the wwires in the well casing going down 150ft had a bad spot in them.

I hope my suggestions help prevent further fustration in atemp to solve the problem!

gj
 
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Old 09-17-00, 08:19 PM
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Had a bad breaker in breaker panel in house. Replaced it, checked for power, shows 240 on meter. It is exactly 100 ft from breaker panel to cut-off switch. It is 5 ft from cut-off switch to pump control box and about 3 ft from box to well casing. Meter shows 240 at cut-off switch and 240 at pump control box. Unfortunately, pump is still not working. What is % of power loss from control box to pump set at 380 ft.? 10-3 is supposed to be sufficient to 500 ft. Am I wrong? Next step is to pull the pump and check the wiring. Sure didn't want to have to do that. I appreciate all of your help.
 
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