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#40086 - 07/12/04 06:00 PM Well pump readings
sparkync Offline

Registered: 10/17/02
Posts: 811
Loc: NC
I went to check out several wiring problems due to lightning today. One of the "hits" was the homeowner's well pump control. It blew it apart and also blew the pressure switch cover off, shorted out a wire and several other items. After installing a new "pump control" box, I thought I better ohm the wires out from phase wire to ground. According to my reading I was showing a direct short from each phase to ground. Since I had remembered in times past about getting some strange readings and at that point there wasn't anything else to do except to try it, I plugged the control in. The pump worked fine, except for a leak we found I don't understand why it didn't short out though. Can anyone give me an explanation of this? I want to make sure there is no safety hazard involved here. The well in about 100ft. from the house and feeds the house with plastic pipe. I don't exactly understand why it is working. I appreciate any input. Thanks Steve...

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#40087 - 07/12/04 06:21 PM Re: Well pump readings
twh Offline

Registered: 03/11/04
Posts: 895
Loc: Regina, Sask.
I worked on one a few months ago. It was 240 volt, 3 wire plus one ground. I assume we are talking about the same thing.

Mine tested grounded at the controller and clear at the pump. The wire had worn through between the plastic line and the casing. Repaired, re-installed and it tested clear with a megger.

Your reading to ground doesn't sound good.


#40088 - 07/12/04 06:54 PM Re: Well pump readings
CharlieK Offline

Registered: 03/10/03
Posts: 23
Loc: Baltimore. Md. U.S.A.
Go to the manufactures web site. I know Franklin Pump has an excellent troubleshooting guide. I do freebie work at a large Boy Scout Camp that has 11 pumps scattered over 2000 acres and have downloaded the info for each model pump. It beats the guess work. Some of the pumps are 300' down.

#40089 - 07/12/04 07:30 PM Re: Well pump readings
sparkync Offline

Registered: 10/17/02
Posts: 811
Loc: NC
Charlie, you don't know the web site for Franklin pump do you? I pulled up one, but they didn't have a troubleshooting guide.
Any other expertise comments would be appreciated. I may try to see if there is a place at the top of the well housing I can check for some kind of voltage. This is an old pump, and there is no disconnect at it, therefore no place to get a good reading.
I want to make sure there is no hazard here
I have to go back out tommorow to replace the part on the storage tank that leaked and need some ideas.
Thanks again, Steve

[This message has been edited by sparkync (edited 07-12-2004).]

#40090 - 07/12/04 07:46 PM Re: Well pump readings
stamcon Offline

Registered: 03/24/01
Posts: 322
Loc: So San Francisco CA
Steve, try this link for a PDF installation/maintenance/troubleshooting download. This info is just for Franklin pumps, but might help some. Troubleshooting is down around page 43.


#40091 - 07/12/04 07:59 PM Re: Well pump readings
SolarPowered Offline

Registered: 07/05/04
Posts: 615
Loc: Palo Alto, CA, USA
From phase to ground, or from phase to neutral? An electric motor has almost zero DC resistance, but the AC impedance at 60 Hz is much higher.

#40092 - 07/12/04 08:13 PM Re: Well pump readings
sparkync Offline

Registered: 10/17/02
Posts: 811
Loc: NC
SolarPowered, it is phase to ground, there is no neutral. It is a 240 volt single phase pump. Thanks, Steve

#40093 - 07/13/04 07:57 AM Re: Well pump readings
n1ist Offline

Registered: 02/13/02
Posts: 176
Loc: Malden MA
Sounds like one wire faulted to ground, and the other one is showing the motor in series with the fault...

A --- MOTOR ---*--- B

If the * is the fault, A will show a little higher resistance to ground than B.



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