help!!

[brandt]

I have a 1/2 hp 115v submersible well pump that is 4 years old. It started tripping the 35 year old 15a breaker last week. It used to buzz occasionally so i figured it was time to replace it . I also replaced the pressure switch because it sparked upon startup and the contacts looked a bit fried.That did not fix it for long.The symptoms were: the breaker would trip occasionally;the pressure switch would turn the pump on and the pump would run for 10 seconds before stopping, then after 40 seconds turn itself on, then run for 10, off for 40 and so on until the pressure was reached then the switch would turn off the pump. After much discussion with many people it was decided that my pressure tank was bad. When i replaced the pressure tank i replaced it with a larger one: a precharged 82 gallon. The old tank had so much corrosion at the inlet it was reduced to about 1/4" also the check valve before the tank was so corroded that it would not function. I replaced the tank, the switch, the pressure gauge,the check valve and lots of plumbing and some valves.I have a 30/50 switch and i set the pressure tank at 28psi.as instructed in the manual. It worked well for a day. I called tech support for the pump and got suggestions for testing the pump.I am getting 122v at the line side of the presure switch,108v while running.I must note that for some reason i do not have a control box. I did an insulation resistance test at the pressure switch and got 400,000 ohms. I did a winding resistance test at the pressure switch and got .9 ohms. Both apparantly within acceptable limits. however when I did an amp test on the hot(black) wire while the pump was running, it read that it was drawing 31 amps. That would explain the breaker. I have a mole problem as well. I am quickly running out of money and cannot afford to replace another component that won't fix it.any help would be greatly appreciated. thank you.

 

[Teets]

high amps

I'd guess you have 2 bare spots touching somewhere. I've run into this where one leg on a 3/4 hp pump was drawing 8 amps and the other was drawing 60 amps. Found 2 bare spots touching 100' down. Replaced the wire and had 0% shorts and good amps and windings on wire and pump.

 

[Sponsor]

 

[Chris75]

If the pump is turning on and off with the pressure switch calling, sounds to me like a problem with the pump. maybe something in the propeller making the pump work harder and thus having the overloads kit in, notice the delay for the pump to start back up again, then shut off, just remember the breaker in the panel is only for short circuit and ground fault protection, the motor overloads protect the wire... The start up of a motor will draw high amperage for only for a short while, a 1/2 HP pump running should only draw about 9.8 amps at 115 volts...

 

[brandt]

help,high amps,pump has a mind of its own

thanks guys. i'll pull the pump to see if anything is blocking pump or worn spots in wire. please keep posting suggestions .i'm still wondering about how to test the wire from the pressure switch to the well pump(about a 50' run of uf cable),having moles and all. Brandt

 

[Rancher]

Proceedure to test the wire for mole/gopher damage:

Disconnect the load. (Pump)
Hook up an electric fence charger, the one that is intermitant, not the continous one.
If you have damage the charger will not hold charge, and you can hear the thump where the cable is damaged.
And you may zap the mole.

Rancher

 

[Speedbump]

That's an interesting test Rancher. I never heard of that one before.

The other way is to twist the two wires together at either end then clip one lead of your ohm meter on one of the ends and stick the other probe into the dirt. If you read less than several Megohms, you should replace the wire. If the ground is wet, you will always get a much higher reading. Getting an infinity reading is the best.

bob...

 

[Rancher]

That's an interesting test Rancher. I never heard of that one before.

During college I worked as an Engineer trainee at one of the copper mines here in AZ, we had a 13 KV cable trenched in, fired it up with no load, and it blew the fuse, the Head EE called one of his power company buddies that loaned us a "thumper", it used the same principal as the electric fence charger, except was probably a lot more KW, we walked the line, 1.5 miles alltogether, and sure enough thump, thump, thump, had it dug up and repaired, we were back in business. I did it on a regular 120 V line with the fence charger, and sure enough it works, and not only tells you the wire is shorting out, but locates it as well, much better than digging up the entire 100' lenght.

Rancher

 

[Speedbump]

How does it locate it when it's buried?

 

[Rancher]

How does it locate it when it's buried?

You can hear it, just like if it's on a fence and a bug gets between the hot wire and the fence, except underground it just makes a "thump".

Rancher

 

[brandt]

I plan on pulling the pump out tonight after work. thank you for all of your suggestions. If that does not show anything then I'll continue to try to find an electric fence "thumper". I'm in maryland and though common in the west, not so much here. I'll post later tonight with an update. Thanks again

 

[Chris75]

If I were checking the insulation I would use a meggar, but I like the other ideas also, around here the wire and water supply are around 4' deep so no mole problems...

 

[brandt]

ongoing saga

Well i pulled the pump and other than a fair amount of rust on the pump(stainless steel) and the screen(plastic) i couldn't find anything glaringly wrong.I split the pump off of the motor and the pump turned very freely with no grinding and even flushed it out to be sure. I cleaned the screen and the pump off and replaced it. I dropped the pump in until the pitless was just out of the well and tested the pump.It still ran for 10 seconds on,40 seconds off and still drawing over 30 amps(it's a 12 amp max pump).I did another ohm test for the winding and insulation at the wellhead and came up with the same numbers.The well is 50 feet deep with water at 21 feet. We are at the "shallow" end of the severn-magothy aquifer, but judging by the stains on the supply pipe the level does not flucuate much.I'm thinking i need a new pump even though this one is only 4 years old(and out of warranty, of course.)Anyone have any other suggestions? Thanks again for the advice. Brandt

 

[Speedbump]

I am getting 122v at the line side of the presure switch,108v while running.

The voltage is a little low and is dropping quite a bit when the pump is running. If this is because of the 30 amps, it makes sense, if not, the wire may be a bit on the small side.

The 400,000 ohms to ground is not a good number. Franklin says to pull the pump if you read less than 50,000 ohms, but at 400,000 it's definately on it's way out if not already dead.

I would say it's time to get a new pump. Submersible Pumps

bob...