well shed timer project

Discussion in 'The Projects Forum' started by dthx, Apr 30, 2016.

  1. dthx

    Thread Starter Member

    May 2, 2013
    194
    14
    I have a 350 ft. well...no city water where I live.
    Single phase 220VAC power comes into my well shed.
    From there it goes to a breaker box that supplies power to my compressor (220VAC) and my pressure pump (110VAC) and lights .
    If I'm away on a trip and one of my pvc pipes or a garden hose connection bursts.....my pressure pump will sense the drop in pressure.
    The pressure pump will pump ALL the water out of my holding tank and the compressor will stay on and try to make it up until I get back from traveling.
    It'll run continuously until it burns up.
    I don't want to turn everything off every time I go to the lake for a day, etc.....
    That would work but I would forget, etc.
    What I need is a timer of some sort that .....
    If the power to my well shed FLOWS for ..say.....15 minutes......the timer will break the connection.
    It has to reset because my compressor comes on to fill the tank up 4 or 5 times per day.
    My well is healthy and the compressor will fill up a 500 gal holding tank in 8 minutes
    This timer would have to go between the power pole and my breaker box.....
    There may be something available commercially....
    Any ideas from the crowd....?
    Thanks
     
  2. Dodgydave

    Distinguished Member

    Jun 22, 2012
    4,974
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    Can you draw what you have electrically wired up,like a circuit diagram.

    the only way i can see this is you have two pumps one fills the tank (Compressor,)
    and one empties it (Pump).

    Sounds like the timer needs to be connected to the Pump pressure sensor, like a timer-contactor,this would feed the supply to the pump?
     
  3. Dyslexicbloke

    Active Member

    Sep 4, 2010
    420
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    That is relatively easy with standard parts...
    You need a basic starter circuit made from a relay, possibly 2 and a timer. A button would 'set the system which then latches in until it is unlatched, by the timer or another button. The timer runs when the pump and or compressor rums.

    Option 1
    If you can read the voltage after whatever switches on the system, IE the pressure/level switch then just put the timer supply there.
    Many universal timers, designed to go in control panels, will accept 24VDC to 250VAC

    Option 2
    If the switched part of the circuit is in the borehole and therefore inaccessible you can measure the current, with a trip amp designed to do the job, and run the timer from that.

    I would add an indicator to show when the system in latched/unlatched...

    would you like a drawing and parts recommendation?

    Of course you could do this hundreds of other, possibly even building some electronic circuit, ways but if you just want a solid control box that is easy to construct this is the way to go.
     
  4. dthx

    Thread Starter Member

    May 2, 2013
    194
    14
    See if you can open this scanned document.
    Then let me know and we can talk about what might be possible.
    I've listed (alphabetically) where a timer might be possible for me to install...but I don't know.
     
  5. Dyslexicbloke

    Active Member

    Sep 4, 2010
    420
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    It would probably be best/easiest to place a current sensor at A with its threshold set so that it ignores the lights but sees the pump and or compressor. You haven't mentioned current for either so it would be hard to recommend parts...

    upload_2016-5-1_1-58-3.png

    The circuit should look like this. Note that a flow switch could replace the current sensor which may be better.
    A 24V control supply, and thus relays and contactors is safer but 230 will be OK if it is done properly in an earthed enclosure.
    NB. I have not shown any circuit protection but you MUST install it. Again not enough info.

    When RLA1 is on Q1 & Q2 are on allowing the system to run as it does now.

    RLA1 is off until BTN On is pushed after which it stays on because it is latched with one of its own contacts.
    The supply to RLA1 is via BTN Off and TMR1, if the timer expires or the button is pushed RLA1 will drop out.

    TMR1 runs when the current monitored by I Sns has exceeded the set point (or a flow switch is closed - not shown) When its time setting is reached it will drop out RLA1 which then stays out, disabling the pumps, until the on button is pressed.

    Hope this helps
     
    Last edited: Apr 30, 2016
  6. dthx

    Thread Starter Member

    May 2, 2013
    194
    14
    Thanks for the time you took to think about this and draw it out.
    The site is great and I've gotten help before.
    Every time I need help with a project I regret not becoming an EE.
    I dont understand much of what you've sent me.
    S0...Let me ask you a question or two.
    Could I put a current detecting device on the incoming power to my main breaker box so that....
    when anything in the well shed begins to run (for whatever reason)....a 0 -10 minute timer starts running and will shut the power to the breaker box off when the time is up.
    Then I would need to be able to reset it so that the process could repeat itself.
     
  7. John P

    AAC Fanatic!

    Oct 14, 2008
    1,632
    224
    If this were me, I'd rig up a current transformer or a Hall-effect sensor on the incoming power line, and build a low-voltage system (isolated from the power line) to read the output of the transformer/sensor, with an output that would drive a relay to interrupt the power if necessary. Obviously the low-voltage devices have to have their own power source, but I assume it would be OK to do this by tapping the incoming line before it feeds into the pump control system.
     
  8. tcmtech

    Well-Known Member

    Nov 4, 2013
    2,034
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    So why doesn't the well water pump pressurize the tank itself like in a normal water system? o_O
     
  9. dthx

    Thread Starter Member

    May 2, 2013
    194
    14
    I like your idea John....I'll explore what's available commercially and talk to you some more about it,
    If my compressor runs longer than 10 minutes continuously, .....something is wrong....(any number of things)....and I want the entire well shed to shut down....
    Mr. tcmtech....
    Thanks for the interest.
    Generally...
    My compressor pumps air down my well and forces the water that is down there up to a 500 Gal. holding tank.
    My compressor can pump enough air to fill the holding tank to the desired level in about 8 minutes.
    The water in the 500 gal holding tank is at ambient.
    That holding tank feeds a pressure pump that supplies water to my house on demand.
    To keep the pressure pump from running all the time, it also puts water into an accumulator tank with a rubber bladder that is charged with air pressure ...to give my pressure pump a rest.....
    When the pressure in the accumulator tank drops below a minimum pressure switch setting...the pressure pump fires up again.....keeping the pressure up.
    So......say for instance......if I'm taking a long shower or washing the car......the pressure pump doesnt run all the time.....it's on ....and then it's off at a minute or so interval.
    But, if a pipe breaks and I'm not at home....then the pressure pump would pump the holding tank dry and the compressor's float would turn the compressor on and the compressor would run until I get home.....
    Compressor and pressure pump running 24/7.......not good.
     
  10. Dyslexicbloke

    Active Member

    Sep 4, 2010
    420
    19
    What I suggested 'is' to use commercially available kit that could easily be 24VDC but it would be cheaper and not inherently unsafe at 220VAC.

    It is measuring current, as drawn, bit could work by looking at a water flow switch.

    Directly reading current could be done with something like this... (And many other similar parts)
    https://uk.rs-online.com/web/p/signal-conditioning/4705850/

    You could use a current transducer and a small signal based device ... (Easier to install, again loads of choice)
    https://uk.rs-online.com/web/p/current-transducers/0198778/
    https://uk.rs-online.com/web/p/signal-conditioning/2365927/

    Of course you could solve this problem literally hundreds of ways but I was assuming that building stuff would be a last resort and that a standard solution from readily available parts would be preferable.

    If you want an actual design with parts recommendations I will need to know what your currents are. (At the very least the wattage of the kit)
     
  11. tcmtech

    Well-Known Member

    Nov 4, 2013
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    I see. There is no electric pump down in the well itself.

    Sounds like a rather discombobulated system to do what should be a simple process and function of bringing water out of a well.
     
  12. dthx

    Thread Starter Member

    May 2, 2013
    194
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    Well....(pun intended).....a very common way of doing it......there is no down hole submersible pump to break down.....they all do and then you have to call the well guy and have him come out and haul the pump out and replace it.....an expensive process......and if he cant get the one you have right away because they are discontinued or something.....you might have to wait......maybe no water for a while....
    Not with a system like mine....
     
  13. crutschow

    Expert

    Mar 14, 2008
    12,995
    3,229
    Yes, our daughter has a deep well with a submersible pump which had to be recently replaced when it failed.
    Think it cost in the neighborhood of several thousand dollars and they were without water for several days.
     
  14. tcmtech

    Well-Known Member

    Nov 4, 2013
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    Not buying it. I have worked on deep well systems for years and they are easily pulled with common tools and garage items if person stops and thinks about it long enough. ;)

    To be honest my well is ~200 feet and I can pull the pump by myself with nothing more than a certain size pipe fitting, a chain and some 2 x 4's with nothing more hand power in less than 15 minutes. Your 350 foot well might require half an hour to set up for or a small tractor or vehicle but still its easily doable. :cool:
     
  15. AnalogKid

    Distinguished Member

    Aug 1, 2013
    4,523
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    It sounds like all of the potential problems are located after the pressure pump, so that is the only thing that has to be controlled. Shut off the pump, and the holding tank is safe. If that is correct, then I think the place for power control is between the breaker box and the pump. No need to shut down the entire shed (including lights) by placing the contactor before the breaker box.

    1. If all of that is good, then we're talking about a SPST or DPST relay in the 110 Vac line to the pressure pump, a much more simple and more safe thing to wire up.

    2. Thinking about when you are home and things are at peak water usage - what is the longest time you can imagine the pressure pump having to run? Is it fair to say that this time plus 25% margin is your timer ON time?

    3. Once the timer shuts off the pump, do you want it to automatically reset after a (probably longer) fixed OFF time, or wait forever until you press a button?

    ak
     
  16. tcmtech

    Well-Known Member

    Nov 4, 2013
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    So why can't a lower limit float be added to the supply tank so that if the water level drops too low it shuts down all power to the air and water pumps until manually reset? o_O

    No estimating of timing involved. If the water demand exceeds the tank refresh rate and the reserve drops too far the system shuts itself down until reset.
     
  17. dthx

    Thread Starter Member

    May 2, 2013
    194
    14
    Yes, AnalogKid..that sounds like the way to go. I'm sure that's what everyone would have suggested if I had explained it "well" enough in the beginning.
    I should have thought of it myself.
    The holding tank and compressor are a separate system. All the compressor knows is whether the tank is full or not...and it can't drain down if the pressure pump is not running.
    So shutting the pump off would prevent that.
    One thing though...think of this...
    Say I set I set my new failsafe timer for 20 minutes....knowing that if my pressure pump ever runs for that long , something is wrong and I want to shut the pump off
    In the normal operation mode my pressure pump runs for a1 minute...and stops for 5 minutes......then it will run for 1 minute and stop for 5 minutes again......over and over while I'm using water in the house.
    Question:
    So does the new timer only kick the pump off if it runs for 20 minutes or would the 1 minute accumulation for twenty times shut the pump off...

    Also thanks for the advice TCMTECH I'm sure you have a system that is right for you.
    I like to never, ever have to worry about anything down the well...I would have to take my entire well shed down to to have enough room to erect 2x4's and a chain hoist above the hole...I'm sure you've run into that with your experience in the industry.
    My well man and I talked about both systems and we decided on the one I have now....that was in 1998 ..with no problems at all so far.....
     
  18. dthx

    Thread Starter Member

    May 2, 2013
    194
    14
    I just read tcmtech's idea......it's a good idea too...
    Good call.
    A Low/Low...!
    I've got some reserve down there in the tank....below the "low" level.
    Gems Sensor and Controls makes some that I used to use......They are simple and my well man will understand em.
    So ....Tcmtech.....my holding tank has float ball that has a brass rod that comes up thru the tank's lid.
    There are two adjustable stops on the rod that actuate a mechanical relay with a flapper on it.
    When those stops hit the flapper they either turn the compressor on or off.
    Water from well goes in...raises float....rod comes up and the lower stop pushes flapper and trips switch...turning compressor off........
    Water usage drops float........upper stop on rod pushes flapper on switch down and start compressor putting water in well
    I'm sure you've seen this before.
    Question.....how would the Low/Low switch be wired in so that it shuts off the compressor AND the pressure pump.
     
  19. tcmtech

    Well-Known Member

    Nov 4, 2013
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    Actually, all you need is common 18" - 24" dia wooden cable spool and enough wood to make it sit just over the well casing. Use the pipe fitting that screws into the pitless adapter on the end of a steel rod to grab the adapter head and pull it up.
    The wells I have worked on I have added a steel cable loop around the pitless adapters so that hey can be hooked with a normal chain hook eliminating the need for the fitting and rod all together.
    Two or three guys and some muscle power are all it takes to pull a pump!

    After that just roll the well pipe over the spool and go out the door with it. If you have a modern well that was made with flexible poly pipe and not a solid steel screwed together design pulling a well pump and everything below ground is very easy.

    Option two for deep well pumping without having a pump downhole is to use a two line system with a water jet eductor at the bottom. The same thing a jet pump has on its nose only mounted remotely down the well.
    Again a very easy design to DIY with little more than two runs of pipe and only one or two other components that are easy to work with.


    Just change out the flapper switch system with another type of switching system like two wire mini float switches that mount through the side of the tank or through a PVC riser pipe assy that mounts beside the tank and use that to control the power to the pumps via NC relays or contactors that open the connection only when they are powered on.

    http://www.amazon.com/Mkele-Side-mo...1462262212&sr=8-19&keywords=mini+float+switch $5.00 each.
     
  20. AnalogKid

    Distinguished Member

    Aug 1, 2013
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    Entirely your call. From your description, a failure mode that emulated an unending string of correct short pressure cycles would be rare if not impossible. So my guess is that the timer would reset itself whenever a pressure cycle ended before the failure timer window ended.
    1. Whenever the pressure cycle ends normally it resets the timer.
    2. If the timer runs out, it stops the pressure pump and disables itself.
    3. Timer is reset reset a button press.

    20-30 minutes is too long for a 555 or other R-C timer to work accurately over time and temperature changes. Better to go with a clock oscillator and divider. A CD4060 or CD4521 plus a few steering diodes can do all of this Both are combo oscillator/counter chips. You already have a switch in series with the pressure pump, so this circuit would drive a relay in series with that switch, between the existing switch and the pump, and take its control input from the switch through an optocoupler or another relay. What is your skill set regarding assembling a circuit on perf board?

    Thinking it through, there are two possible ways to reset the system.

    4. If you trust that a failure always presents as a continuous pressure demand, then the circuit can be powered by the AC going to the pump. In normal operation, a pressure request powers up the timer, which has a power-on reset circuit. Timer runs while the pump is running. When the pressure request is fulfilled, the pressure switch turns off the pump and the timer. Next request, power on, power on reset, etc.
    In a failure condition, the timer runs out, disables downstream power to the pump, disables the counter so it doesn't come around in another 20 minutes and enable the pump again, and just sits there with a constant pressure request at its input and a disabled output. Resetting the timer with a pushbutton switch (in parallel with the power-on reset) resets the system.

    5. If it is possible for the pressure request input to go away while the system is sitting in the pump-disabled mode, then the timer circuit has to be able to tell the difference between the pressure request ending before the timer has expired (normal operation) versus the request ending after the timer has expired (error condition). This takes a a flipflop or latch chip added to the timer output, and now the timer circuit has to be powered continuously rather than only when the pump is running. Not a big deal at all, just a control function decision.

    ak
     
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