Submersible pump mystery

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Ballvalve

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OK - 800' deep well. Set the pump at 300' due to very high water level about 8 years ago. Added a Franklin pump saver box. Pumping up a hill to a static tank that is about 60 PSI on the gauge when full. Perhaps 140' height. I wrote on the control box, 150PSI test pressure and 9.3 amps draw - 1 HP.

Filled the tank nicely for those ten years. Only pumped it for a few hours a week over those years. Now I still get the 9.3 +/- amp draw, but only 40 PSI dead head pressure. Won't make the tank. Whats the mystery? Clean clear water, no sediment. I must say that I had to set the pump saver or pump tek box at 40% from the get go to get it to run without a trip, so I was outside of range to begin with. Its not tripping at 40, but it will at 45 instantly. Need more stages in the pump head?

Reading the pumptek manual, I will guess now that the pump deadheaded and I have some melted impellers due to a bad match of motor to pump head. Looks like the Pumptek is not dependable on reading a deadhead condition. [?]
 
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Valveman

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My guess is the pumping level in the well has dropped 50' or so, and the pump can now only produce 40 PSI instead of 60 PSI. Check the pump curve to see if that pump can even lift from 440'.

It should be drawing less than 9 amps when deadheaded unless it is a Pentair brand 10 GPM pump. Those don't seem to drop in amperage as they should. There should be a big difference in amperage from pumping water to running dry, but sometimes not so much difference in deadhead amperage. A Cycle Sensor is adjustable down to 1/100th of an amp. It also looks at amps times the power factor, which gives you more precise measurement. You can even set a Cycle Sensor to shut the pump off when the water level drops to a certain point. It doesn't have to be deadheaded or pumping air to know the difference.
 

Ballvalve

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My guess is the pumping level in the well has dropped 50' or so, and the pump can now only produce 40 PSI instead of 60 PSI. Check the pump curve to see if that pump can even lift from 440'.

It should be drawing less than 9 amps when deadheaded unless it is a Pentair brand 10 GPM pump. Those don't seem to drop in amperage as they should. There should be a big difference in amperage from pumping water to running dry, but sometimes not so much difference in deadhead amperage. A Cycle Sensor is adjustable down to 1/100th of an amp. It also looks at amps times the power factor, which gives you more precise measurement. You can even set a Cycle Sensor to shut the pump off when the water level drops to a certain point. It doesn't have to be deadheaded or pumping air to know the difference.

Thanks. Its a Franklin on a Myers - Graingers head. I probably mixed up motors and heads when I installed it, so I don't really have a curve. might have the # of stages written down, will check. As to amps, I used a good digital meter and a old amprobe mechanical one - both show almost no difference from dead head to full open, maybe 9.3 or 9.2 down to 9.1, much the same as at install. Good thought on the water level. Not a welcome thing though. I know I was pushing the limit with the 60psi to make the tank.
 

Valveman

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The motor doesn't matter. Myers-Grainger same thing as far as I know, still made by Pentair. Which is why you won't see much of an amp drop with a 10 GPM series. There 15-20-25 and up do a little better. Then when you get to the large pumps they have one of the best amp drops with restricted flow.

But you would still be able to set a Cycle Sensor at 9.1 amps.
 
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