My solar deep well pumping system

Ralph Kettell wrote:

Phil Gardener wrote:I doubt it would be a problem if the relay is over-rated, since the amount of current will not exceed the max.

To Phil and Gerry (re. relays),

30A relays are fine, 100A would work fine but would be a bit bulky.  The only issue is that many relays are only rated for AC or they have a reduced rating for DC.  As Eric explained in his video AC automatically breaks the circuit 60 times per second.  DC never breaks and so the relay needs to be designed in such a way to insure that the current is quenched.  This needs to be done in such a way that does not degrade the life of the relay contacts.  Arcing can be a nasty problem especially if it is repetitive.

Eric if you have any electrical problems or questions, PM me.  I  am a PE with an MS in Electrical Engineering and 40 years of experience.

Sincerely,

Ralph

Hi Ralph,  One thing I've noticed is that when the water pressure gets to 28psi, the relay kicks on and clicks once, then when the water pressure reaches around 48psi it starts clicking on and off very quickly (perhaps 5-20 times) before it stops. The shurflo pump takes longer to get the pressure up those last 5 psi (or so) and because of that, I think its riding that inbetween state where it can't decide if its on or off. You mentioned that repetitive arching will cause a shorter life of the relay so how would I prevent this rapid cycling? (The relay I'm using is rated for 30amps AC.) Thanks!

Hi Gerry,

I have an idea as to what is happening.  When it kicks off the pressure drops rapidly and the pressure sensor does not have sufficient hysteresis for some reason and it immediately kicks back on.  Having done this several times, it eventually gets to a point where three pressure doesn't drop out so quickly when the pump cuts off and it stays off.. It should not be doing it.  Do you have a pressure gauge that you can watch while the pump is shutting off.  See if the pressure bumps around.  Try running the test when there is no water usage while the pump is running and then also run it a couple times with different amounts of water running while the pump is about to shut off.  Can you send me a photo of your pressure sensor.

Thanks.

Sincerely,

Ralph

Hi gerry what I think happens is as the pump head rotates it temporarily goes above the required pressure and turns off then the chamber it's on bleeds a bit and it falls below pressure so it has trouble reaching it's set pressure. I found the pressure switch on the shurflo too sensitive and limited which is why I suggested a stand alone full size pressure switch. Like this one   https://www.amazon.ca/Electric-Pressure-Control-Switch-Adjustable/dp/B079QJX8HN/ref=sr_1_2_sspa?s=hi&ie=UTF8&qid=1548642716&sr=1-2-spons&keywords=pressure+switch&psc=1
Canadian link given only for an example. The nice thing is they will last for 40 years, have a sizable switching mechanism in them and are fully adjustable both on and off pressure and the differential between them. Its rated for ac so again use it only to trigger the dc relay not switch the pump...  all that might be overkill but that is how I solved that very annoying continuous switching as the shurflo reached shut off pressure.
Cheers,  David

Gerry Parent wrote:

Ralph Kettell wrote:

Phil Gardener wrote:I doubt it would be a problem if the relay is over-rated, since the amount of current will not exceed the max.

To Phil and Gerry (re. relays),

30A relays are fine, 100A would work fine but would be a bit bulky.  The only issue is that many relays are only rated for AC or they have a reduced rating for DC.  As Eric explained in his video AC automatically breaks the circuit 60 times per second.  DC never breaks and so the relay needs to be designed in such a way to insure that the current is quenched.  This needs to be done in such a way that does not degrade the life of the relay contacts.  Arcing can be a nasty problem especially if it is repetitive.

Eric if you have any electrical problems or questions, PM me.  I  am a PE with an MS in Electrical Engineering and 40 years of experience.

Sincerely,

Ralph

Hi Ralph,  One thing I've noticed is that when the water pressure gets to 28psi, the relay kicks on and clicks once, then when the water pressure reaches around 48psi it starts clicking on and off very quickly (perhaps 5-20 times) before it stops. The shurflo pump takes longer to get the pressure up those last 5 psi (or so) and because of that, I think its riding that inbetween state where it can't decide if its on or off. You mentioned that repetitive arching will cause a shorter life of the relay so how would I prevent this rapid cycling? (The relay I'm using is rated for 30amps AC.) Thanks!

Gerry, that's a wonderful result!  That confirms why those pressure switches burn out so often.

When my shur flo pump would get to the point of just about to shut off, it would kind of slow down and almost growl before it kicked off completely.

Picture this scenario with me.  Envision I am standing at a light switch. If I turn on the switch the bulb comes on fully bright.  If I turn off the switch, the bulb is fully dark.

Now envision the amount a time it takes to count to 1 second.  If I was super duper lightning speed quick and I flicked this light switch off and on so that during the time period over one second, the switch was in the on position 50% of the time and off 50% of the time, that same light bulb would appear to be HALF as bright as normal, you would never see the light blinking, our eyes don't register that fast.

This scenario is exactly what is happening with your pressure switch in the pump.  The only way for that relay to click on and off is if power is removed to the coil in the relay, via the pressure switch, and then turned back on.  So as that pump comes up to pressure, that pressure switch is sitting there cycling on an off about a gillion times.  Wayyyy more then the clicks your counting on the relay I would say, your only hearing the ones that turn off for quite some time. That's what made my pump sound like it was slowing and almost growling, it must have been turned on and off a bunch before finally reaching pressure and shutting off for good.  The relay works quite slow, and holds some residual magnetism in the moments of it turning off, so the 5-6 clicks you hear are nothing compared to what that little shurflo pressure switch was doing....and imagine that tiny switch carrying the full load of the motor while cycling like that!! It's no wonder they burn out!

Now where do we go from here?  Option A, leave it alone.  The relay is designed to carry this load.  These relays are designed to be turned on and off tons of times.  If it's somewhere where you can't hear it, and the function of the water system is fine, lets leave it and see how long the relay lasts, but I bet it will last a long time

Option B, Ralph can help us with this.  Since the shurflo pressure switch is turning on and off that many times, we need a way to smooth that power signal coming from that switch so that power to the coil in our relay is not interrupted.  If we were to wire in a capacitor in that wire leading from the pressure switch to the relay coil, it would fix the cycling of the relay.  A capacitor is basically an electronic device that stores electrical energy, just like a battery, but they can't store it for long periods of a time.  They self discharge quite rapidly.  I've taken them apart before and its basically 2 metal strips isolated from each other with a gooey electrolyte....so it really is a battery, just a sucky one that doesn't hold a charge.  

With a capacitor wired in the circuit, when the shurflo pressure switch cycles off, the capacitor will provide power to the relay coil so it does not collapse and shut off.  When the power shuts off for good from the pressure switch, the capacitor will bleed off over a second or two and the relay will shut off.

Ralph should be able to help us with the size of the capacitor......that's out of my area of expertise, I'm more of a trial and error, beat stuff with a hammer type of guy.

Honestly, I wouldn't even worry about option B unless you just really hate the sound of the relay clicking(that is if the water system is working fine and that's your only concern)

David Baillie wrote:Hi gerry what I think happens is as the pump head rotates it temporarily goes above the required pressure and turns off then the chamber it's on bleeds a bit and it falls below pressure so it has trouble reaching it's set pressure. I found the pressure switch on the shurflo too sensitive and limited which is why I suggested a stand alone full size pressure switch. Like this one   https://www.amazon.ca/Electric-Pressure-Control-Switch-Adjustable/dp/B079QJX8HN/ref=sr_1_2_sspa?s=hi&ie=UTF8&qid=1548642716&sr=1-2-spons&keywords=pressure+switch&psc=1
Canadian link given only for an example. The nice thing is they will last for 40 years, have a sizable switching mechanism in them and are fully adjustable both on and off pressure and the differential between them. Its rated for ac so again use it only to trigger the dc relay not switch the pump...  all that might be overkill but that is how I solved that very annoying continuous switching as the shurflo reached shut off pressure.
Cheers,  David

Thanks David.  You know his set up. I do not.  That was why I asked for a photo of the sensor.  My response to him was going to be to recommend the precise or practical equivalent of the device you suggest.  I have two of them in my water system.  One to control the deep well pump, and one for pumping out of my tanks.  I have a more substantial pump.  It is a 3/4 HP shallow well pump and both systems have pressure tanks so they can be operated independently.  I can switch the water several different directions to inside outside, filtered, unfiltered, etc.

Sincerely,

Ralph

Hi Eric and Gerry,

I sent our tried to send a detailed response and my phone managed to lose it.  I will re do the message tomorrow and resend. Sorry for the technical glitch and the attendant delay.

Sincerely,

Ralph

Hi Ralph, David and Eric,  
So here's what the gauge is doing when the pump is running: The needle is vibrating back and forth very fast (maybe about 1-2 psi) and seems to be in sync with the pump vibration. When it was just about 48psi, this time it took about 20 seconds of on/offs before it finally stopped. The first 5 seconds were strictly on/offs from the relay and the final 15 seconds of on/offs from the relay and the pump. Getting late, so that's all the testing I can do for tonight...

I'm totally ok with just leaving it the way it is as the sound doesn't bother anyone in the pump house.....just want to make sure its not burning more than the switch or relay.

Switching over to a full sized pressure switch is certainly doable... heck, I might even have one in the garage somewhere hiding out that I can try if you think this is a better way to go.

Here is my pressure gauge located right before the pressure tank and pump setup.

Hi Gents,

This is my third attempt to post this.  Each time prior when I would go to hit post, I would lose coverage on my phone it would bomb and I lost the entire text.

Here goes.  I would say that Eric is probably right and the relay should not fail at least not too soon.  Sooner than it should given the pump pulsing on and off but still a good ways on the future.  However, my thought is that the pump itself may prove to be a bit less happy about the constant banging on and off that it is getting.

If it were me, I would replace the control and hook it up the right way, but I am not your dad so you will get to pick the path to travel.  I would like to remind Eric that he had to help out his neighbor when his well ran dry.  If this is your primary source of water at least have the parts on hand to fix it if it fails at the worst possible time.

As for fixing the problem electrically, we can take a good stab at it.  We do not know exactly how long we need to hold the pump on when it first indicates it is at pressure.  You can run some tests to help with this. You will need to run the test with no water running in the house while the pump is pressurizing, also with a moderate flow and then with a heavy flow, but not so heavy that the pump cannot ultimately get to pressure and try to shut off.  Have a stopwatch handy and when it begins to pulse hit your stopwatch and count how many times it pulses on and off for each of the three scenarios.  Write down the total time and number of on/off cycles.  Also any notes during the test also may be helpful or you could even simply record the test on your video of your phone and post them.

I will also need to know the system drive voltage, the voltage and current rating of the relay coil, coil resistance, relay drop out voltage or simply post a link to the data sheet for the part.  We could end up with quite a large capacitance to keep it from dropping out.... so you may need a few components, a switching transistor, a couple diodes, resistors and capacitors.  This way we can make so it is safe, the pump starts with a very short (faster than you can notice) time delay and a very long hold time without having a humungous capacitor.

I sure hope it posts this time.

It posted this time Ralph.  Thank you for your persistence in helping out.  Maybe third time is a charm!  Looks like there may have been a bit of a glitch today.

Ralph Kettell wrote:Hi Gents,

This is my third attempt to post this.  Each time prior when I would go to hit post, I would lose coverage on my phone it would bomb and I lost the entire text.

Thank you for your perseverance!   :)

Here goes.  I would say that Eric is probably right and the relay should not fail at least not too soon.  Sooner than it should given the pump pulsing on and off but still a good ways on the future.  However, my thought is that the pump itself may prove to be a bit less happy about the constant banging on and off that it is getting.

If it were me, I would replace the control and hook it up the right way, but I am not your dad so you will get to pick the path to travel.  I would like to remind Eric that he had to help out his neighbor when his well ran dry.  If this is your primary source of water at least have the parts on hand to fix it if it fails at the worst possible time.

When you say replacing the "control" I'm assuming you mean the pressure switch that's built into the pump with one that David recommended? So far we have an extra set of micro switches, a set of relays and also a whole new pump, so we've got the backup end of it covered.
EDIT - Looking at to purchase this one: pressure switch However, in the description it says: "Can be wired 115-Volt or 230-Volt". So can it also be wired also for 12VDC? If so, should I leave the relay connected to to help this switch not to burn out prematurely as well?
EDIT2 - Looking back at what David said about getting a full sized pressure switch: "Its rated for ac so again use it only to trigger the dc relay not switch the pump...  all that might be overkill but that is how I solved that very annoying continuous switching as the shurflo reached shut off pressure." ... which answers my question.

As for fixing the problem electrically, we can take a good stab at it.  We do not know exactly how long we need to hold the pump on when it first indicates it is at pressure.  You can run some tests to help with this. You will need to run the test with no water running in the house while the pump is pressurizing, also with a moderate flow and then with a heavy flow, but not so heavy that the pump cannot ultimately get to pressure and try to shut off.  Have a stopwatch handy and when it begins to pulse hit your stopwatch and count how many times it pulses on and off for each of the three scenarios.  Write down the total time and number of on/off cycles.  Also any notes during the test also may be helpful or you could even simply record the test on your video of your phone and post them.

Will have some time tomorrow so I'll do those tests then and post the results. Sorry, don't own a phone but I'll take some pictures if it would help.

I will also need to know the system drive voltage, the voltage and current rating of the relay coil, coil resistance, relay drop out voltage or simply post a link to the data sheet for the part.  We could end up with quite a large capacitance to keep it from dropping out.... so you may need a few components, a switching transistor, a couple diodes, resistors and capacitors.  This way we can make so it is safe, the pump starts with a very short (faster than you can notice) time delay and a very long hold time without having a humungous capacitor.

Shurflo pump
Relay info that we have installed now.
The backup relays are here: backup relay info

Hi Gents,

I just responded to a post by Amanda Pennington in the plumbing forum.  She had her pipes freeze and needs help.  I started by asking her a few questions, but if some of you able bodied folks might be able to help.  it sounds like related problems to what you have been solving in this thread.  I will continue to help, but it is always better to have several heads looking at a problem.

Sincerely,

Ralph

Hi Guys,   OK, today I purchased a pressure switch Everbilt 30/50 and would like to wire this into the system rather than using the existing pressure switch on the shurflo pump. Does this schematic look OK?

Gerry Parent wrote:Hi Guys,   OK, today I purchased a pressure switch Everbilt 30/50 and would like to wire this into the system rather than using the existing pressure switch on the shurflo pump. Does this schematic look OK?

That pressure switch should have heavy duty contacts like the relay, making the relay redundant and not necessary now. However, your diagram would work.

Thank you for the thumbs up Eric. Should have time to install it tomorrow.

Gerry Parent wrote:Thank you for the thumbs up Eric. Should have time to install it tomorrow.

Just saw your post Gerry.  Yes that will work, but I would suggest wiring it directly as Eric had said. Those contacts are rated to do the job without the relay.  The reason for doing away with the extra parts is reliability.  The less parts you have, the less things that there are to fail.  The Kiss principle applies here.

Happy pumping!

Sincerely,

Ralph

Finally got around to wiring things up. Took your advice and hooked it up without the relay. Only stood by it for one fill but it worked fine. One click on and one click off....OH yeah!

The only question I have now is why does the pressure tank feel empty when I jiggle it even when its supposed to be mostly filled with water when it reaches 50psi?

Gerry Parent wrote:Finally got around to wiring things up. Took your advice and hooked it up without the relay. Only stood by it for one fill but it worked fine. One click on and one click off....OH yeah!

The only question I have now is why does the pressure tank feel empty when I jiggle it even when its supposed to be mostly filled with water when it reaches 50psi?

Have you checked the bladder pressure when there is no water pressure.  It may be too high which might explain some of the strange things you were having happen with your prior controller.  The pressure should be a couple pounds lower than your lowest operating pressure.

Sincerely,

Ralph

It was 28 psi when the tank was empty Ralph. My new pressure switch is set to come on at 30 psi.

Hi gerry so glad that fixed it. peak in on the contact every now and then to see if its carbonizing. If it isn't, all good if carbon builds up do the relay. As to the tank the water is actually in the rubber bladder not the steel tank so it should not jiggle too much. If its not storing enough water drop the tank pressure a few psi at a time until you come to the right balance. You want a good continuous discharge rate not an ebb and flow. There is also adjustment on the pressure switch the big nut does on off pressure the small one does differential between on and off pressure...
Cheers,  David

I would think that the tank should be quite heavy.  Heck a 20 gallon tank at 6 lbs to a gallon should weigh 120 lbs full right? I would bump the tank pressure down a bit.  Those pencil pressure gauges arn't the most accurate things in the world.  When cars were mandated with tire pressure monitor systems in 2007-8 I was a firm believer in a digital pressure gauge.

Thanks David and Eric,   I havn't noticed any pressure drops at 28psi so I'll take it down in increments as suggested and see if that increases the amount of water in the tank without too much of a lapse in water pressure at the taps. I'm using an analog tire gauge to check the tank and an analog pressure gauge as well and they register pretty close to each other.  
Funny though, I lightly rock the the tank back and forth and it feels like there is nothing in there (even makes a hollow ping) but yet when the water is turned on, a fair amount comes out before the pump kicks back on (so water must be getting into there).
One thing I've noticed that's different with this 12v pump vs a submersible well pump is that the pressure gauge will drop and rise dramatically (from 28psi to about 38 psi) but then only very slowly creep up or down (between 38-50psi). Not a problem, I guess that's just the torque difference in amps between 220v and 12v and the gallons per minute each is rated for.

EDIT - Reduced pressure in the tank (when empty) to about 23 psi. When I turned the water back on, this time the gauge jumped from 0 to about 28 psi very quickly then slowly up to about 50 psi when it shut off.  There was no way I could delicately  jiggle that tank anymore! Definitely water in it now!  Thanks Guys!