Low flow well Pumptec failure will Cycle Sensor work?

[CST]

I have a low flow well, pump at about 350 feet. single phase 3 wire 1 H.P. motor. This pumps into a 1000 gal cistern, with another 1/2 H.P. pressure pump suppling water pressure. This last summer, the Pumptek module quit working on the well pump controller, i replaced it.
 Then recently, I believe i had another Pumptek module failure, as the well pump/motor would not start until i removed the Pumptek module.  It may have been damaged during a power outage in the area.  I've been running the well motor/pump manually.  What i've found, is I start the well pump and it draws right around 10.5 amps, i run it for around 13 minutes, it slowly drops to 10.25 or a bit less amps and i shut it off.  That adds approximately 1/4 level of the cistern, in height, so im guessing over 100 gallons of water.  I leave the pump off for a day or two, then repeat the process.  I tried shorter cycling up to two times in a day, with best results as stated previously.  I'm wondering if i could us Cycle Sensor in place of the Pumptek module.  Like set the Cycle Sensor to shut off at 10.25 amps, stay off for 48 hour, then come back on.

Thoughts, suggestions, question?

Thanks!

[Cary Austin]

A 1HP has a mx amps of 9.8, so at 10.5 the Pumptec maybe shutting off on high amps, not low amps.  When that pump runs dry it should drop to 4-5 amps.  The Pumptec looks for a 25% drop in amps and shuts off on underload for dry run.  It should drop to 7-8 amps before the pumptec will shut it off for running dry.

The Cycle Sensor can be set to turn the pump off at any point you desire.  But it only has 5 hours of off time max before the pump will restart, which should be fine or even better than waiting 24 hours.  The Cycle Sensor does not trip on high amps, as there is an overload in the motor to take care of that. 

I am afraid the pump/motor is already damaged, which is why it is showing higher than 9.8 amps. 

[CST]

Thank you for your reply Cary and i had a suspicion something was wrong, and your explanation make sense to me.  I'm going to try and limp by with what i have to get the money together and I'll probably replace the whole works, as far as the well motor/pump piping and wiring is concerned.  With your knowledge, what do you think caused the pump/motor damage?

I did a little research during my first foray into this well and found some information about the max amps on 4" 3-wire 1HP Franklin motor i didn't really understand Full Load 8.2 amp vs. Maximum Load being 10.5.  I later found an invoice from 1999 that show a Gould 1hp 10gpm sub pump, and i'm guessing would have similar specs as Franklin.

[Cary Austin]

The Franklin book I use is from 1992 and says 9.8 amps max on a 1HP.  The 2015 book does say 10.4 amps, but that was after your pumps date.  If it was installed in 1999 you got three times the average life of 7 years already.  The most usual cause of a motor failure is from cycling on/off too much.  But pumping into a cistern doesn't usually cause cycling.  Run times or off times shorter than 60-120 seconds will also cause a heat build up in the motor.  Even just having a top feeding well can cause motor heating.  Running out of water often and for too long can also cause motor damage.  Probably a combination of all the above was your problem.  Nothing that can be fixed anyway.  Just be prepared to replace it and run it until it won't start anymore.

[CST]

Yes, i'm going to be replacing it for sure.  Thank you again on your information on the function of the Pumptek module. 

Not wanting to add anything that will reduce the life of pump/motor, just read your sticky on multiple check valves, with one being your thought on a better setup and am curios as to what to look for when replacing my setup, with the pump sitting at 320 feet?

Also, what is your logic for "But it only has 5 hours of off time max before the pump will restart, which should be fine or even better than waiting 24 hours", i would have thought if i cycle the pump less often, that would be better, as i assume if my well's low flow is typically tripping on the underload setting, that it would do so until my cistern fills and is shut off by the level sensor.

Also i forgot to ask, would one use your cycle sensor, instead of the Pumptek module, or in addition to?

I'm learning as i go, so understand i maybe asking questions that seem pretty elementary to you, i've already learned quite a lot from you and you've confirmed some things i wasn't sure about.  Thank you.

[Cary Austin]

I would still only use one good metal, spring loaded, poppet style check valve at the bottom of the 320' of pipe.  Any other check valve further up the system just gives the water a place to crash into when the pump starts.  The water held by a bottom check valve smashing into a closed check valve with water holding it closed, and causes massive pressure spikes that can destroy anything from the faucet the water is coming out of to the thrust bearing at the bottom of a submersible motor.

With a weak well you only need to delay the restart of the pump long enough to allow the pump to run at least a minute or two when it comes back on.  There is also no sense is waiting a day or two if the well completely recovers in a few hours, which is usually the case. 

Even when the well takes a long time to fully recover, you can get more water out of the well by turning the pump back on sooner.  The lower you keep the water level in the well the faster the water refills to a point.  Keeping the down hole pressure low allows the well to refill at a faster rate, up to a certain point.  So, by only delaying pump restart long enough to allow the pump to run for a minute the next time, you will get many more gallons from the well than if allowed to recover longer. A normal example would be 20 minutes off and one minute on, until the cistern is full and the float switch is up.

The Cycle Sensor would replace the Pumptec.  We had to make our own device because many like the Pumptec look for a 25% drop in amps and shut the pump off thinking the well is dry.  However, when you restrict the pumps flow with a ball valve, because it is a low producing well, or when you restrict the flow with a Cycle Stop Valve the amps will usually drop more than 25%.  The well is not dry, but the Pumptec thinks it is, and shuts the pump off.  The Cycle Sensor is just infinitely adjustable.  The Cycle sensor can be set to know the difference between a pump that is simply pulling low amps because it is restricted, and a pump that is pulling slightly lower amps because the well is really dry.