Intermittent pump on well.

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Sans1964

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Gentlemen I agree with what you are saying to a point. I do not think the well is dry. My reasoning follows
1. I measure 200 feet of water in the pipe. The pioe is 6 inches. Approximately 300 gallons? ??

When I did the on off the second time it was only a minute or 2, from the 4 amp condition also it has been fine since that post. If the well was dry I dont think it would recover in that short of time? ?

Crap I dont know. I guess ill have to wait till it does it again run out and measure the well right then. Thing is none of the neighbors are having problems and next door neighbor s well is less than 500 feet from mine and half the depth. And they have no problems.

Arrrrrgggghhhh
 

Valveman

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The only other thing that could make the pump drop from 7 to 4 amps is a plugged line. Maybe your check valve is bad and occasionally it will get pushed up too far and act like a plug in the pipe. But it sure acts like it is pumping the well dry.
 

Ballvalve

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How about throttling the well way back so its only pumping about 1/4 or less of it's its capacity and watch the amp draw for much longer. This may not tell you if you have a bad check valve, but if it gives you water in your house, you have time to keep testing and opening the flow until you go to 4 amps again. Perhaps at say, 2 GPM, you keep the 7 amps, and water, you have a low capacity well, or a check valve that only get's funny with a high flow.

My neighbor @ 3,000 away, same strata seemingly, drilled 4 wells and finally got 3 gpm. I am in the same valley, same driller, and have a 50' well and 50 GPM. Then I drilled a well when I split my land: up a steep hill out of my valley, about 1000' away horizontally and 100' higher than my ground level. Same driller got 10 GPM at 120'. Now figure that one out!
 

Craigpump

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Or the head broke off the stem in the check valve and occasionally hits the seat in such a way as to shut off the flow of water.
 

Craigpump

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Water travels through fractures that's why it's so hard to predict what aWella depth will be.

I've drilled many 200' wells that make 10-15 gpm then moved 20' away, drilled 600' with 5 gpm.
 

ACWxRADR

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Scott, Valveman and Craigpump,

I really do not know how submersible pumps are configured, so I may be totally off base with my assumptions. I am trying to explain Scotts measurement of 7.7 amps and 4.5 amps. Why the difference may exist.

But, if it were like my shallow well pump motor, it would have an internal centrifugal switch and at least one capacitor, a START cap. It may also have a second capacitor, a RUN cap.

When the pump first turned on, the power would be applied to the START capacitor and the motor windings. During the initial startup the motor RPMs are low and the contacts of the centrifugal switch would be pulled closed by a set of springs. These contacts connect the START cap which allows a high inrush current to provide high starting current and torque.

As the motor RPMs increase, the contacts of the switch would be thrown outwards by the centrifugal forces until they overcome the strength of the springs and the set of contacts open which disconnects the START cap. Now the motor does not require the extra current or torque from the START cap because it is up to near full speed.

If there is a RUN cap, then the switch would make a second set of contacts to engage that cap. Otherwise, it would just be the motor windings alone, with no cap at all. In this condition, the motor whirs along at full RPM and a much lower current. Once it has the water pumping and the inertia of the motor's rotor going along, it doesn't need much assistance to keep on turning at this speed.

Therefore, when it initially starts up, there should be a higher current measurement. Once it is up to full speed, the current should drop back substantially.

So, when you measure the start up current at 7.7 amps and then it drops down to 4.5 amps, this is actually a normal and desired operation for an external, above ground pump motor like mine. I am not sure if a SUBMERSIBLE pump motor is set up this way, although I can't speculate how it would work if it were not.

Now, if there were a wiring problem (high resistance due to numerous broken conductors), there may be a LOW VOLTAGE condition at the pump motor. If this were the case, then the motor would turn slower, maybe so slow that it could never build up enough speed to activate the centrifugal switch and hence the current would always measure high (7.7 amps) because the START cap is always in the circuit.

My problem now with my theory of the broken conductors in a multi-conductor cable is that the 7.7 amp start up current sure sounds about right to me. If there were enough broken conductors to affect the motor RPMs, I would expect the current to be lower. So I am now unsure of the diagnosis. Something is not adding up here, and it sounds like Scott is pretty sure of the water level in the well.

Do submersible pumps have centrifugal switches? I can understand that they must be constructed with extreme attention to size and weight. I have used pumps that do not have such switches, but they usually are not very robust and do not pump a great deal of volume or pressure.

RADAR
 

Craigpump

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When a submersible pump is pushing water the amps are high, in this case 7.7. When there is no load on the pump, like when the well is pumped dry, the amps will drop off. If the pump is pumping against a closed valve, the amps will drop. If the pump is pumping, but the pipe is broken the amps will be high.

No centrifugal switches, a three wire pump uses a control box with a relay either mechanical or electronic.
 

Valveman

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Scott, Valveman and Craigpump,

I really do not know how submersible pumps are configured, so I may be totally off base with my assumptions. I am trying to explain Scotts measurement of 7.7 amps and 4.5 amps. Why the difference may exist.

But, if it were like my shallow well pump motor, it would have an internal centrifugal switch and at least one capacitor, a START cap. It may also have a second capacitor, a RUN cap.

When the pump first turned on, the power would be applied to the START capacitor and the motor windings. During the initial startup the motor RPMs are low and the contacts of the centrifugal switch would be pulled closed by a set of springs. These contacts connect the START cap which allows a high inrush current to provide high starting current and torque.

As the motor RPMs increase, the contacts of the switch would be thrown outwards by the centrifugal forces until they overcome the strength of the springs and the set of contacts open which disconnects the START cap. Now the motor does not require the extra current or torque from the START cap because it is up to near full speed.

If there is a RUN cap, then the switch would make a second set of contacts to engage that cap. Otherwise, it would just be the motor windings alone, with no cap at all. In this condition, the motor whirs along at full RPM and a much lower current. Once it has the water pumping and the inertia of the motor's rotor going along, it doesn't need much assistance to keep on turning at this speed.

Therefore, when it initially starts up, there should be a higher current measurement. Once it is up to full speed, the current should drop back substantially.

So, when you measure the start up current at 7.7 amps and then it drops down to 4.5 amps, this is actually a normal and desired operation for an external, above ground pump motor like mine. I am not sure if a SUBMERSIBLE pump motor is set up this way, although I can't speculate how it would work if it were not.

Now, if there were a wiring problem (high resistance due to numerous broken conductors), there may be a LOW VOLTAGE condition at the pump motor. If this were the case, then the motor would turn slower, maybe so slow that it could never build up enough speed to activate the centrifugal switch and hence the current would always measure high (7.7 amps) because the START cap is always in the circuit.

My problem now with my theory of the broken conductors in a multi-conductor cable is that the 7.7 amp start up current sure sounds about right to me. If there were enough broken conductors to affect the motor RPMs, I would expect the current to be lower. So I am now unsure of the diagnosis. Something is not adding up here, and it sounds like Scott is pretty sure of the water level in the well.

Do submersible pumps have centrifugal switches? I can understand that they must be constructed with extreme attention to size and weight. I have used pumps that do not have such switches, but they usually are not very robust and do not pump a great deal of volume or pressure.

RADAR

What you are describing is how any pump starts. Above ground pumps have centrifugal switches to shut off the starting capacitor, submersibles have a relay in the control box to shut off the capacitor. However, starting amps for any pump is usually 6 to 9 times the running amps. So a 7 amps motor will actually start at 42 to 63 amps, (see locked rotor amps) and drop back to 7 amps when the switch or relay kicks out the start capacitor.

If the pump is drawing 7 amps it is pumping maximum flow rate. If the water is not going into the tank, there is probably a broken line in the well or underground. There is very little difference between the low amps from pumping the well dry and the low amps from a plugged line or closed valve. The pump will draw 7 amps when pumping max flow. It will probably drop to 4.5 amps when it is pumping against a closed valve or a blocked pipe or check valve. And it will probably drop to about 4.0 amps if it is pumping air as when the well is dry.

I just don't know if the 4.5 amps is from pumping the well dry or if it is from a blocked pipe or closed valve. If you are sure there is plenty of water above the pump, then it has to be a blockage in the pipe or check valve as it is acting like it is pumping against a closed valve.
 

ACWxRADR

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Thanks for explaining this operation with a submersible. I had a hard time imagining enough space inside one for the hardware.

I can believe a stuck check valve. I installed a new well for my sister a couple years ago. I reused much of the plumbing, but decided to put in a NEW check valve because the existing one was ancient and had been used on several old wells and was even laying in a shed for years.

With the BRAND NEW check valve installed. The system ran fine for a week or so, then no water. I finally determined that the check valve had stuck closed. A few raps on the valve with a soft-blow hammer would free it up, but it would stick again and again.

When I finally got around to taking it out, the poppit was stuck in the valve seat. To free it, I tried to push it with a screwdriver. It was stuck so tight that I had to tap on the screwdriver with a hammer! I talked to a neighbor who is a well driller and he said "I bet it is a Water Source" brand valve, and it was. He said he has found a history with this brand sticking closed in this fashion. Evidently the seat and poppit are machined incorrectly, wrong angle or something.

I put the ancient, beat up check valve back on and it has been running fine ever since.

RADAR
 

ACWxRADR

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Valveman,

Rethinking this with your statements in post #30 I believe that broken wiring (not completely broken or open, just numerous single conductors in a multi-conductor cable) may still be a legitimate and viable root cause of the problem Scott is experiencing. Hear me out and humor me for the moment while I explain my theory.

If Scott's pump motor should draw 40 to 60 amps at initial start up and then drop back to 7-8 amps at normal water flow, but he measures only 4.5 amperes when it is not pumping water, couldn't it be that there are so many broken conductors that the pump is operating with a greatly reduced voltage and current? He obviously cannot measure the current and voltage directly at the pump motor, only at the output of the controller, so we must deduce what is truly happening at the motor.

The current output from the controller must be the current at the motor (unless it is bleeding off to ground somewhere else prior to the motor - not likely as that would typically result in a dead short) but the voltage at the motor could be substantially lower than the voltage measured at the output of the controller. If the voltage at the motor is very low and the total current is also low, then the motor would run at a greatly reduced RPM and probably and eventually overheat and go into a thermal overload condition, thus shutting off completely to protect itself.

I believe that what needs to be known is what current draw Scott's motor should measure when pumping water normally under ideal circumstances (i.e. no stuck valves, no plugged screens, no low water level and no highly resistive wiring). If it should be 7 to 8 amperes after the start windings have been switched OFF or out, then the 4.5 amps he measures when the pump is not pulling water is abnormally low and it indicates a high resistance load, an additional load more than just the load of the pump motor itself.

If all the information provided so far is absolutely correct, then I am led to my original assumption that there is a wiring problem between the controller output and the motor input. As Scott stated, the wiring is the only hardware item left from the original setup. Which also leaves me with legitimate suspicions.

Do you think my point is valid? I would really like to see Scott not have to do too much work or spend too much money. It would be great if the true root cause were identified before he does either.

RADAR
 

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Amps are inversely related to volts. If you have low voltage, the amps will be higher, not lower. I still think it is a stuck check valve because if the wire were "almost" broken, it would not pass enough current to start the pump.
 

ACWxRADR

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Cary,

Your statement that amperes (electrical current) and voltage (electrical potential) are inversely proportional is not correct. They are actually the reverse, these two variables are directly proportional according to Ohm's law.

This is because there is something else that one needs to consider in the equation, which is the load (the resistance or impedance) of the motor or other device. The current, voltage and impedance are all interrelated in the equations of Ohms law.

https://en.wikipedia.org/wiki/Ohm's_law

I=E/R E=IR R=E/I

In our discussion regarding Scott's well, if the wiring en route to the pump has broken conductors creating a higher resistance (more resistance than just the pump motor itself), and the supply voltage from the controller is maintained at 120 VAC (or 220 VAC) then the current in this series circuit must decrease.

What your previous statement is eluding to is the voltage drop of the supply source or the output of the pump motor controller. If the load increases (let us say that our pump motor windings partially short out and its resistance or impedance DECREASES). It becomes a greater load and now draws more current or amperage. If the supply source or controller cannot handle this additional load, the output voltage of the controller starts to drop lower and lower as this load increases. This is because the internal resistance of the power source itself (the controller) becomes a greater percentage of the total load than just the motor itself. Therefore the output voltage of the controller drops lower and lower as the load increases.

Therefore, you are incorrect because you are not taking the ENTIRE circuit loading into account. You are assuming that the higher load (increased current) is related to decreased output potential (voltage) and a decreased load (less current) would make it appear that the output voltage from the controller increases. The problem with this is dependent upon where you are taking your voltage measurements.

Since we cannot place a voltmeter directly across the leads right at the pump motor in a submersible pump, we have to realize that the wiring en route to that motor also has a voltage drop and must be considered to be a "load" all on its own.

Gordy (aka RADAR)
 

Valveman

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The load of the motor does not change. 1HP = 740 something watts. Volts X Amps = watts. So if the load (watts) of the motor stays the same, when the voltage drops the amps increase, and vice versa.

A 1/2HP motor at 230 volt draws 6 amps. The same 1/2 HP motor running on 115 volts uses 12 amps.
 

ACWxRADR

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Cary,

That is entirely correct, but you are now introducing a totally different scenario into this situation.

You are assuming that the total load (the pump motor plus the wiring supplying power to the motor) has not changed.

If the motor remains the same load, but the wiring becomes a resistive load in itself, then the current goes down because the overall load or demand on the supply (voltage source) is LESS. The wiring must be considered to be an additional load if it is not sized appropriately for the current draw of the motor or if there are broken conductors which make the conductor less capable of carrying the necessary current to the motor of the pump. The more LOADS connected in series, the lower the current will be in the whole series circuit.

If you had a perfect pump motor and perfect wiring and you could dial down the output voltage of the controller, then the current draw of the motor would increase. It would run at a slower RPM, heat up and eventually trip a thermal or overcurrent protection breaker.

However, we are assuming that the controller output is stable, not low in output voltage and the pump motor loading is not increasing due to any defect to the extent that the controller output cannot handle the increased current. I believe Scott stated that both the controller and pump were new? They are supposed to be new and working appropriately. If true, then we have to look elsewhere for the problem. Not to be naïve enough to realize that a new pump or controller could NOT be defective, but I don't suspect this.

Gordy (AKA RADAR)
 

Reach4

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However, we are assuming that the controller output is stable
There is no controller. OP has "2-wire" pump.
Your theory is that there is an intermittent resistive connection. I believe the experinced people are not saying that is impossible, but they are saying that there are more likely explanations.

OP's wife is probably saying that the water needs to work, and that should be a priority. A call to a well person if symptoms com back will probably be money well spent.

A submersible pump does not have a foot valve.
 

ACWxRADR

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Reach,

I don't disagree with that at all. However, Scott has stated that NEARLY everything has been addressed already. Almost everything being newly replaced or verified. Except one item, the wiring down the well string. This we know has not been addressed, as far as Scott's information has indicated. If he is correct and honest about all this, then I personally must suspect the wiring for lack of any better culprit.

It seems to make sense to me, especially the current measurements. But, there may be information missing that would confirm and verify or discount this as the problem. I think we need a few more assured measurements, but I am seriously leaning towards the wiring. I cannot see anything else other than what Valveman suspects about the stuck check valve, but I have a gut feeling that the valve is not the problem in this specific case.

Gordy
 

ACWxRADR

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There is no controller. OP has "2-wire" pump.
Your theory is that there is an intermittent resistive connection. I believe the experinced people are not saying that is impossible, but they are saying that there are more likely explanations.

OP's wife is probably saying that the water needs to work, and that should be a priority. A call to a well person if symptoms com back will probably be money well spent.

A submersible pump does not have a foot valve.

Reach,

Yeah, I have been reading so many other posts that I forgot that Scott doesn't have a controller. But, that should not change Ohm's law or how things work with or without a controller.

I am sure that his wife is livid without water at the most inopportune moments, but I would beat myself up more than my wife would if my water didn't work. That's a personal, "man-thing"... You understand. It is akin to knowing how to change a tire, change oil, tie a fly for fishing, clean a fish, dress out a deer or cut down a tree properly. This is something that a person, a guy or gal, just MUST figure out! It is sort of a personal vendetta.

I would not wish to call in a professional. I would rather study and learn the system so that I was the professional. We can all do this, if we have the time for it. People, all people are going to have to start learning how to do these things for themselves very soon. Times are going to get bad, very bad. It isn't going to be as easy to get by in life when shit hists the fan. Even the Great Depression is going to look like a day in the park compared to what is going to happen in the near future. I want to be prepared. I say this and I am not even a conspiracy orientated activist! I am a realist.

Gordy
 

Craigpump

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Probably not the wire.

Most pump guys use a solid core pump cable. If the wire was so beat up that it only had occasional continuity, the wire would be so chaffed that the breakers would trip.

Probably not the splices either, most guys do a good job of securing them to the drop pipe with tape.

Unless I missed a post, everything has been done except pressure testing the offset pipe and a pump down test on the well.
 
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