Backup Power and 1/2 HP Flotec 230V Deep Well Submersible

Discussion in 'Pumps and Tanks Well Forum & Blog' started by SnittyKitty, Sep 4, 2008.

  1. SnittyKitty

    SnittyKitty New Member

    Messages:
    4
    I have a Flotec 1/2 HP 230V Deep Well Submersible Pump with a 19 gallon pre-charged bladder/tank. I'm exploring several options as to how to address when we lose main power and we lose our well. I have a 5250 watt generator and of course the first thing that pops into my mind is simply run a wire from the generator - problem solved! Before I go that route I wanted to look at a different solution in regards to backup power for example using in series/parallel 24V DC with an inverter and free the generator strictly for the house itself. The home we have is a repossession which we're restoring. On the outside of the house is a separate breaker for the well pump; it's a 40 amp breaker which given the fact I have a 1/2 HP pump and the specs say it pulls 5 amps. Watts equal Volts times amps or 1150 watts. A well pump does not run constantly but at the same time, it will come on at unpredictable times based on use. I want my solution to be unattended, so when I lose power I don't have to worry about losing water. There are simpler solutions like using a 1500 or 2000 watt inverter hooked up to a running vehicle but I'm curious if there's anyone out there who has dabbed into backup power and powering their wells and is the wattage I've calculated correct? Thank you.
  2. Redwood

    Redwood Master Plumber

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    7,453
    Location:
    Connecticut
    Not quite automatic, and you will have to watch how many things are on at once...

    [​IMG]
  3. Bill Arden

    Bill Arden Computer Programmer

    Messages:
    584
    Location:
    MN, USA
    Motors have two current draws.
    1. Starting current
    2. Running current
    1/2 hp = 370 watts, but I would use the 5 amps just to be safe.

    I would suggest not worrying about loosing water.

    I use a 3000 watt UPS for my computers, but what is wrong with loosing water?

    I have a 120V well pump, a 3000 watt UPS and yet when I have a power failure, I don't even care if I loose water.
    If I have to... I can start my 4500watt generator and back-feed power.

    PS: They make this simple leaver that mounts on your main panel where you have to turn off the main breaker in order to turn on the generator back-feed breaker.
  4. speedbump

    speedbump Previous member

    Messages:
    4,540
    Location:
    Riverview, Fl.
    You do realize that for this system to be automatic, someone has to start the generator each time they want water. Right? Either that or your going to be putting a lot of gasoline in that thing.

    bob...
  5. SnittyKitty

    SnittyKitty New Member

    Messages:
    4
    Thanks for your replies

    1st Bill - Thank you, you're referring to a double pole switch or some kind of manual/automatic transfer switch, correct? Three thousand watts for your computer?

    2nd, Bob - Thank you, before I opt to install a manual transfer switch, I wanted to explore alternative solutions that kept my well off that generator or if need be buy a generator sized specifically for the well or run an inverter from a vehicle to do the work. You're exactly right, the only way to pull water is to go outside and fire up the generator to fill the bladder, but as you see to run the generator any longer is wasteful.

    It crossed my mind to use an inverter, but then again, that too might be defeating the purpose too. Bill has indicated to me that 1/2 hp is 370 watts and if only 370 that plus a factor of 1.5 for startup of the well pump or round numbers, 600 watts might be all I need to accomplish the task.

    I am by no means an electrical expert, but my pump is 230V, I'm not aware a small inverter has a 230 outlet, though I've read something about stacking the inverters, but neither am I one to play with electricity for the sake of experiment; frankly I wouldn't know how to do that or make the attempt unless I'm positive I can do it right the first time.

    I want to explore the idea of using a 24 volt battery backup system that would use a trickle charger to keep the battery(ies) charged and an inverter. Power outages have never lasted more than one day where I live and that ideally is what I'm looking for.

    Is this feasible?

    Thank you!
  6. Bill Arden

    Bill Arden Computer Programmer

    Messages:
    584
    Location:
    MN, USA
    I work at home and have to run lights and equipment off of the UPS along with my File server and water based computer cooling system.

    1. Pumps don't like the square wave that most small inverters use.
    Modified sine wave = square wave with a zero volt gap.

    2. You can't tie multiple inverters together.

    3. You can use a step-up transformer to convert 120 volts to 240 volts IF the UPS puts out a "true sine wave"
    FYI: A 1000 watt Toroidal transformer is about $150

    4. The 5 amp number is probably it's start up current, This means you need to be able to produce 1200 watts to get it to start.

    If you want to go the UPS route, Your best option would be to find a used UPS with a "true sine wave" output.

    FYI: I payed ~$600 for the 3000 watt "true sine wave" output UPS I use, but remember that batteries will go bad over time and used UPS's generally need batteries. I got luckily in that the eight 12-volt batteries in my UPS have lasted over 6 years, but it's only a matter of time...
  7. Bob NH

    Bob NH In the Trades

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    3,317
    Location:
    New Hampshire
    I installed a filtration system that runs off a solar-charged battery system. The inverter is a top-quality sine-wave inverter by Xantrex that cost about $2500 when they installed it. The pumps came later.

    The 2500 Watt inverter was able to start a 1/2 HP motor with about a 40 Amp Locked Rotor current.

    The best motors for those applications are Permanent Split Capacitor (PSC) motors as they have the lowest starting current. The 2-wire CentriPro motors that Goulds now uses are the only submersible PSC motors that I have seen.
  8. speedbump

    speedbump Previous member

    Messages:
    4,540
    Location:
    Riverview, Fl.
    I'm not sure where Bill got that number. My 1/2hp motor which has a 1.9 service factor would use 1357 watts to operate. This does not take into account the starting current needed. Don't worry about your Flotec motor having a high service factor. It probably has none at all. It's more than likely 1.0 sf. Which would be around 900 watts. The multiplier for starting current on a standard capacitor start motor is usually 3 to 5 times running current.

    BobNH is right on the PSC motors but I wasn't aware that the Pentec or ITT motor was a permanent split capacitor motor. But whatever it is, it's too new on the market to take a chance on it anyway. I would stay with a proven brand. Emerson and Magnetec both make PSC jet pump motors.

    bob...
    Last edited: Sep 5, 2008
  9. alternety

    alternety Like an engineer

    Messages:
    650
    Location:
    Washington
    Be sure to price batteries before you decide what to do. It takes a bit of work to decide what you need. If you use a 12V battery, that would be 50A for a 600W load. Watch wire size. Going to 24V or 48V makes for lower current and smaller wire, but is expensive.

    Batteries should be a deep discharge type (not an automobile starter battery). Bateries should be protected from cold and serious heat. They need to be checked for electrolyte level regularly. They will emit hydrogen and must be vented (if you are using flooded cells). There are gel and ones with the electrolyte absorbed into the separator material. They don't gas but are more touchy about proper charging.

    To get long life, the charging and discharging must be appropriate to the battery. Discharging the battery to less than 50% (there are other numbers) will shorten life. The charger should be one that is smart enough to do it right. Outback, Xantrex, and others make inverters with built in chargers.

    Figure out how long you want to be able to run the pump before you deplete the battery. Then the 0.6 KW X run hours is 1/2 the capacity of the battery you need. Note that you need to know what the specified KWH for the battery is at your specific current draw. The available total power available decreases as the current draw increases.

    A good inverter (Outback and the rest in that class) usually have a pretty good capability to take short term surges (e.g., motor starting). Check the specs. You can if you wish stack two inverters and feed the whole house with 240V (see manufacturers specs). Remember, if you have only 120V from the generator coming into the box, if you connect that to one of the hots and ground, only half your house circuits will be energized. If you try to connect the generator to both hot wires, anything running on 240V won't work. I think that if your house wiring shares neutrals in some cases you could overheat the neutral doing the parallel thing.

    You would want to use a real transfer switch. I believe square D makes a mechanical link that lets you use the breakers in the box to switch. Of course the breakers in question need to be in the righ places for it to fit. I would strongly recommend you not attempt to do this by manually opening and closing the breakers individually. This could hurt someone working on the power line if you got it wrong. I suspect code would want a transfer switch. I have not looked at it cause I would not do it without a transfer switch.

    Go through your house and figure out what load you would need to have running during a power failure. Maybe you can just connect the generator to the house and pump. You should keep in mind what the load would be if you were managing for a power outage and what might be turned on when the power goes out. With a manual transfer switch you can go to the box and turn off big/unneeded circuits and turn off excess things that were running.

    I did some arithmetic in my house and I believe I can run the house on a 5-6KW generator with some load management. My well pump only draws about 500W and does not have the surge on start characteristic of more common pumps.

    Don't forget you have to have a place to store fuel. I am going with propane because it is easy to store, clean burning, and does not spoil when stored, and is the most expensive alternative. You can get a conversion kit for gas to propane engine. Propane is particularly good in this application becasue if you don't need it it will still be undeteriorated. And you don't have to keep going out in the rain/snow to add fuel.

    I was rather thinking about a battery bank kept on float charge when the power grid was running and go through an inverter when power fails. The transfer switch in the inverter is designed to be grid attached is so fast even you electronics is not likely to see the switch. It is basically a whole house UPS. The problem is that it is very expensive. I could sort of justify it if I had solar collectors, but it is a hard sell just for backup. I would use 2 Outback inverters, get a smart motor starter to run the electric start Honda generator, and work out a charger for when the inverter is running. This may or may not need extra equipment: I have to read the manuals. Doing this would not use the generator to directly supply power to any load. It all goes through the battery bank.
  10. SnittyKitty

    SnittyKitty New Member

    Messages:
    4
    Generators & Well Pumps.

    Can an independent properly sized generator be made to run automatic - turn on and off with the need to fill a pre-charge tank or external storage tank? I can't remember the website, but I remember seeing someone use a separate water storage tank; 300 or 500 gallon and placed the darn thing between the well pump, used some sort of floater switch and then sent the water to the pre-charged tank to be sent to the house WITHOUT the use of a 2nd independent pump; is this feasible?

    Thanks to everybody; it's deeply appreciated!

    Bill
    Opelika, AL
    Last edited: Sep 6, 2008
  11. Redwood

    Redwood Master Plumber

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    Location:
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  12. alternety

    alternety Like an engineer

    Messages:
    650
    Location:
    Washington
    I don't know how electronically/mechanically adept you are, but yes it can. If you don't have the skills don't do it. These people http://www.atkinsonelectronics.com/ have a control for running the generator. It needs a single input for start/stop. The controller would need power. You could probably get that from the generators starter battery. You are going to have to figure things out and rewire some stuff.

    The problem is getting that signal. If you pump had been 120V you could have used the second set of contacts to run the generator. A 1/2 horse motor could have been built to run on 120V but from your post it is 140V. Simply using a second pressure switch would be too dangerous. It is not likely to exactly track another switch and could keep the generator running when the pump is not on. I do not remember seeing a switch with more contacts. Try searching the manufacturers site and see if you can find one with one more contact. If there is one for 3 phase that would get you the extra contact. If you can find one, replace the existing switch. This is the best way.

    You could put a microswitch up against the moving part of the relay. You need to find a way to insulate the device. Then that, with a small DC voltage, would control the box. Again you may be able to use the generator battery. One caution is that while actually cranking the battery voltage will drop. Make sure the voltage does not go low enough to make the control signal stop the generator. Look at the current and voltage needs of the controller and you may just be able to use regular old flashlight batteries to power the signal line. One could also use a LED/photo transistor to control things by sensing when the moving part blocks the beam. You can get a small assembly with a slot in the middle to do this if you can find a good place to install it on the pressure switch. That will need a bit of external electronics. Another possibility is a small magnet on the armature and a reed relay mounted and adjusted to pull in when the switch closes.

    You probably want to use a larger than normal starter battery. You will be starting without running long enough to recharge the battery. The controller will monitor the battery voltage and run the generator when the battery needs to be charged. This is also probably a real good thing for generator life, but I assume you won't be using it all that much.

    You must use a transfer switch. If you run the generator only when the pump needs to run; what will you do for powering the house?


    WARNINGS

    Remember - you are messing with 240V on that pressure switch. You must use an approach that will not carry that voltage outside the cover of the switch. The moving part of the switch has a lot of exposed surface that is live.

    Make sure that the generator exhaust can not get into the house. Has to be outside, away from building air intakes and operable windows.

    You must have a transfer switch. The generator and switch must absolutely prevent the generator from coming on either with the grid power on or the grid connected when power is off. In the first case bad things will happen to the generator. In the second case you could kill someone.
    Last edited: Sep 6, 2008
  13. alternety

    alternety Like an engineer

    Messages:
    650
    Location:
    Washington
    Re the idea of a storage tank without a separate pressure pump. Generally no.

    Using an unpressurized tank the only way to get pressure in the house would be to put the storage tank high enough to generate enough pressure. If you did that you would have to have a second pump to get full pressure. You don't want to fill the tank and then just let it sit until the power goes out. But if it was made to be the normal route within the system the water would stay fresh. Remember that storage tank would have to be vented.

    With the well filling the storage tank and the second pump doing pressure, if you could get some tank height, you could bypass the pressure pump when power goes out and get a little bit. But you would need to power the generator every so often if you empty the storage tank.

    I think you would probably be better off with a controlled generator.
  14. Bob NH

    Bob NH In the Trades

    Messages:
    3,317
    Location:
    New Hampshire
    I bought a 5.5 kW Kipor diesel generator because I use fuel oil for heating. Therefore, I always have fuel on site.

    I checked the generator capacity by turning on a 1.2 ton (14,400 BTU per hour) A/C and then started a 1 HP motor on my table saw. The generator didn't have any problem.

    I connected my generator to the Square D QO panel using a UL Listed interlock kit. The interlock kit is also available for the Sqaure D Homeline panel.

    The interlock kit is mounted on the panel with the backfed breaker in the upper-right column. The interlock requires that the main breaker be disconnected before the backfed breaker can be switched on. The process is: (1) Turn off main breaker to get handle out of the way of the interlock; (2) Move the interlock to get it out of the way of the handle of the backfed breaker; and (3) Turn on the backfed breaker.
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