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Posted By: Shinkman Loose neutral ??? - 05/09/03 08:58 PM
Customer installed a surge protector on TV and Stero equipment. He states after doing so his Tv and Stero keep turning on and shuting off all by them selves. He states the surge kicks into (low)?? and this stsrts happening. He also states this on off cycle happens exactly at the same time his Well pump starts and stops. He has a single phase service 400 amps. The Well pump motor is three phase, so I guess he has some kind of transformer just for this well pump. He states that he also is bothered by constant static when playing the radio--------the static comes and goes with the on - off of this pump. He states his oven takes forever to heat up (electric) and a hair dryer does not get hot enough.

I have not been to the house yet but want to have my bases covered in case its not something obvious. What are your thoughts on this problem? Thanks
Posted By: Obsaleet Re: Loose neutral ??? - 05/10/03 02:18 PM
I'm lookin forward to hearing what you find.
Obsaleet
Posted By: mlk682 Re: Loose neutral ??? - 05/10/03 02:47 PM
Whatever it is I think it will be pretty obvious when you get there,let us know what you find. I recently replaced a panel. To the naked eye it looked fine but the nuetral lug had burnt off behind the plastic so it was a little tough to find. Good luck.

What reason would they have for running three phase on just the well??

Mike
Posted By: Bjarney Re: Loose neutral ??? - 05/10/03 05:20 PM
Does the “static” noise and electronic-equipment misoperation occur only when the pump magnetic starter changes state—id est, on startup and shutdown—or for longer intervals? Are the pump and residence served from the same utility-owned transformer?

It is possible that the pump starter is chattering, from something like a loose connection in its control circuit or poor contact continuity in a pilot device, like a pressure switch. Excessive chattering should be given immediate attention. Not having seen the installation, these comments are speculative.

Approach the complaint logically and try to eliminate one potential cause at a time. It’s likely that there is no association between pump operation, surge protector and loose neutral. Try not to let preconceptions or “free advice” cloud your troubleshooting judgment too much.
Posted By: Zapped Re: Loose neutral ??? - 05/10/03 05:31 PM
Any dead bodies buried under the house? Sounds pretty ghostly to me... ;-)
Posted By: zapped208 Re: Loose neutral ??? - 05/11/03 12:01 AM
I find it hard to believe that there is a 3phase well pump in this house, especially with a single phase service. Would like to hear more details. All these problems sound interesting.
Posted By: Bjarney Re: Loose neutral ??? - 05/11/03 01:23 AM
zapped277 — This is a good application for a “two-can” open-delta-secondary 240/120V 3ø 4w transformer bank. The transformer that feeds both loads could be 25-75kVA (1ø) with an additional 10kVA (1ø) unit for the 3ø load.

The arrangement is very common in some areas for small “ranchettes” where there is a 1ø meter (400-amp household service) on a residential or domestic power rate and a 3ø meter on an agricultural or water-pumping rate, serving up to a 15hp pump.
Posted By: zapped208 Re: Loose neutral ??? - 05/11/03 10:34 AM
Bj,- The well pump could also be fed from a 3 phase service from another building.
Posted By: CDN_ELECTRICIAN Re: Loose neutral ??? - 05/12/03 12:48 PM
Does he have a single phase to three phase convertor connected for the pump?

There are several types of devices that convert 3 phase to 1 phase. (1 is sort of electronic the other is simular to a motor (rotary convetor))

If so either of these could create electrical noise on the rest of the houses electrical system and may very well create static and wierd things happening such as turn on other electronic equipment such as TV's and radio's.

Something to look into, i guess.
Posted By: zapped208 Re: Loose neutral ??? - 05/13/03 09:31 AM
Hard tell,n not know'n til Shinkman gets back to us.
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