Pondering power backup options for my well pump

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I really should plan things better... last year, I bought a very nice 2000W 120V Honda generator. That was sufficient for my needs at the old home. Then, I moved... new house has a well. I'm guessing what I have won't be sufficient, but I'm not 100% sure since I'm not well familiar with well pumps, and I also hate to have to buy a second generator, and I'm not sure how to tell.

I can't tell much about the well, except that it is on its own service panel with a single 240V breaker, each half of it 20 amps. They said the well is 250 feet deep. The pressure tank says it is 33.4 gallons and currently reads 50PSI. Can I safely assume the generator can't power this, even if I could figure out how to convert 120V to 240V and wire it in (it's hard wired of course, no convenient plug)? I can do math but I would also guess the full 20 amps aren't actually used by the well pump, so I probably can't figure out how much power it need just by calculating the maximum that can go through that service panel. Why do they require 240V anyway? Seems it could be done easily with 120V.

Anyway, am I out of luck? Do I need a 240V generator and if so what would a suggested wattage be? Could I do something cheaper/clever that'd use the generator to charge up a battery which could then power the well pump for brief periods?
 
First I'm not an electrician, but:

The breakers are sized to handle the peak load on start-up. The higher voltage is used for the same reason it's higher voltage on the transmission lines - 240v @ 20 amps equals (more or less) 120v @ 40 amps. The higher voltage is more efficient. Domestic services are 240, "split" to 120, so the higher voltage is there to be had.

Watts = volts x amps (more or less). An AC motor will not run on a battery. You could, in theory, use a battery and an inverter, but they don't like motors starting up.....

ETA:

The name of the well company should be on the equipment. I'd contact them, and ask what they recommend. You're likely not the first person in the area to be in this situation, and they may have a "here ya go" solution.
 
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I run inverters 95% of the time, either a single EU2000i or 2 of them tethered for heavy use, but when I need my well I switch over to a regular generator that will give me 220 at the transfer panel to run the well.

a cheap generator will work, I went with a 5000 watt Honda EG5000 but a 500 dollar home depot special works well for sporadic use
 
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Could I tether two Honda's together, or does that only double the wattage instead of the voltage? Although another thousand is more than a full sized generator I will probably have to buy anyway. Is my best bet to just have this wired into the service panel? I would prefer not to have to open the pressure switch and remove the wires from it and rewire into a generator each time the power goes out.
 
There are several ways to do it. Two batteries in series will give you double the voltage, but this will not work with AC generators.


From your description, I'd get a Sparky to install a manual transfer switch, with one side going to a plug-in for a separate generator. Your current machine will not work (if its only output voltage is 120), so dedicate that to the rest of the house.

Seriously, as I added to my post...get professional help. You don't want to make a mistake that fries your motor.....
 
OK I do not advocate people play electrician, wiring is not a hobby, but this is how I have my house set up.

I have a 10 circuit transfer panel fed wit a piece of 10-4 from a weatherhead in my garage. The generators stay outside and the cable from the inverter/inverters/or generator come in through a doggy door.

2 of the 10 circuits are to power the 220 well pump. I only flip those 2 switches when I am on my 5KW machine.

When I run my inverter or tether them together for more capacity, I am limited to 4 circuits on the right side of the panel, because the 5th breaker is half of the 220 supply for the well.

I have a adapter cable that goes from the inverter to the weatherhead and only feeds one side of the panel. That gives me heat, lights, TV, internet and keeps the fridge running.

My advice would be for you to save up for a transfer panel, 85 feet of 10/4 cable ( 10-3 w/ground, Romex type NM-B 600Volt rated), a weather head, a cheap 5KW generator and the services of a licensed and insured electrician to do it right.


When I need the well, I swap over to the generator, takes about 5 minutes, then I have my well, and 8 other circuits ,the 4 mentioned above, the well, my garage door openers, my front yard and driveway lighting, and a couple of other things that escape me at the moment.

It isn't a bad setup, if I swap between having the fridge and the heat on I can get away with using only 1 inverter, when I go to work and the TV and electronics are off one inverter runs the heat and fridge just fine.
 
I've been meaning to get around to this myself. The well is my only real concern during a prolonged outage as we can heat and cook with wood. That said I do have a gennie because I like air conditioning and snowtober almost interfered with a new episode of the walking dead.

I recently borrowed a buddies kill-a-watt and I'm going to use that to measure the draw on the pump. Using a handy dandy calculator I'll figure out how big of battery bank I need just for it, and can buy a dedicated inverter. None of this will be connected to the house, going to treat the well completely separate as bigger inverters get expensive and so does professional wiring.

To charge the batteries I have two options, keep the batteries charged either through the wall or buy a solar panel or three. Obviously the solar panels would be required to get utility out of the well after a few days without depending on the generator. I could keep the charger on the wall and only use the solar panels during outages, that would avoid me needing to roof mount them as I could just put them on a mobile stand.
 
Get a second generator for the well pump.

A small generator/inverter, e.g. Honda EU2000/2000i is great for small blackouts or to run a fridge, microwave, etc. But it's not going to power on a well pump.
 
Just another thought here too: Ask yourself why you need the well pump. I know that has an obvious answer, but what do you need the water for?

If it's just for cooking and cleaning, and you have the space, get a Poland Springs style water dispenser and several 5-gallon jugs (get an appropriate amount of jugs).

This is definitely more economical than getting another generator, transfer switch, inlet box, cables, installation, etc.

Food for thought.
 
You need to find out how big your pump is to know for sure if you need to use a different generator. To get 220v from your honda you just need a step up transformer. I use the EU2000 to run a 1/2 hp compressor all the time (not 220v tho).

Another option you might want to look at: what is the static water level in your well? Many wells have water at less than 20 ft. If so there are cheap surface mounted pumps that might be easier to power. You never know when your pump will die having a backup is a nice option.
 
Just another thought here too: Ask yourself why you need the well pump. I know that has an obvious answer, but what do you need the water for?

If it's just for cooking and cleaning, and you have the space, get a Poland Springs style water dispenser and several 5-gallon jugs (get an appropriate amount of jugs).

This is definitely more economical than getting another generator, transfer switch, inlet box, cables, installation, etc.

Food for thought.

During the ice storm of 08 and last years October snow storm, I was damn grateful my Generator was able to run the well pump. In 08 we didn't have power for a full week. I still had to get up and go to work every day, I wouldn't have been real happy if I went without a shower for a full week. I'll bet those around me wouldn't have been real happy either. For me being able to have heat and water was worth every cent.
 
Just another thought here too: Ask yourself why you need the well pump. I know that has an obvious answer, but what do you need the water for?

If it's just for cooking and cleaning, and you have the space, get a Poland Springs style water dispenser and several 5-gallon jugs (get an appropriate amount of jugs).

This is definitely more economical than getting another generator, transfer switch, inlet box, cables, installation, etc.

Food for thought.

Really....you just need the jugs of water......
 
Just another thought here too: Ask yourself why you need the well pump. I know that has an obvious answer, but what do you need the water for?

If it's just for cooking and cleaning, and you have the space, get a Poland Springs style water dispenser and several 5-gallon jugs (get an appropriate amount of jugs).

This is definitely more economical than getting another generator, transfer switch, inlet box, cables, installation, etc.

Food for thought.

I speak from snowtober experience... the wife gets really pissed when she has to melt snow in buckets for a couple of days to flush the can.
 
Just another thought here too: Ask yourself why you need the well pump. I know that has an obvious answer, but what do you need the water for?

It's kind of nice to have. While if the world had just ended, I would not be too concerned about getting by with scooping water out of a brook to drink - I'd live with the discomfort. Before total SHTF, I'd still like to be able to do things such as shower during an extended power outage. Last year, I ended up showering at work during the week my power was out. But, I live far from work now.

I'm not sure how I find out the details of the well I have now except by trying to find who installed it and ask? It's a small town so I suspect the number of well installers are small.
 
you can buy a used "contractor screamer" generator to do your pump for 300 bucks if you need 220, a good electrician should be able to wire a code compliant disconnect to get it off the house wiring with a weatherproof connection outside to plug the generator into for getting it powered up.

I allowed 2 slots on my transfer panel for the well, the inverters only feed one side of my transfer panel, but when I plug the generator in I get all 10 circuits including my well pump.
 
This is wrong, you need 2 separate phases to make 220 and you cant get that off of a 110 generator.

No, its possible.

240V household power isn't really 2 phase, its 2 legs of the same phase. You would need a similar transformer to what is used on most utility poles, just with a different turns ratio.

Trust me, I'm an engineer.

To get 220v from your honda you just need a step up transformer. I use the EU2000 to run a 1/2 hp compressor all the time (not 220v tho).

You can get the voltage, but you won't have enough current from a 2000W generator. A 240VAC circuit at 25A is 6000W. Your 2000W generator can do 1/3 of that amount of power. Inserting a step up transformer is going to eat up some of that due to its inefficiency, so you will probably end up closer to 1200-1500W. You aren't going to start a submersible well pump with that.


The idea of having jugs of water has been brought up by some and dismissed by others in lieu of having a generator, but remember, if your well pump burns out (and they do on occasion) you will be out of water anyway.
 
If he has a 1/2 hp pump it might be possible to start one....it's only about 10 amps. Adding the eu2000 companion should be more than capable.

Also if his pump is one of the grunfos soft start series it should start fine with a smaller generator.

More details needed....
No, its possible.

240V household power isn't really 2 phase, its 2 legs of the same phase. You would need a similar transformer to what is used on most utility poles, just with a different turns ratio.

Trust me, I'm an engineer.



You can get the voltage, but you won't have enough current from a 2000W generator. A 240VAC circuit at 25A is 6000W. Your 2000W generator can do 1/3 of that amount of power. Inserting a step up transformer is going to eat up some of that due to its inefficiency, so you will probably end up closer to 1200-1500W. You aren't going to start a submersible well pump with that.


The idea of having jugs of water has been brought up by some and dismissed by others in lieu of having a generator, but remember, if your well pump burns out (and they do on occasion) you will be out of water anyway.
 
If he has a 1/2 hp pump it might be possible to start one....it's only about 10 amps. Adding the eu2000 companion should be more than capable.

Also if his pump is one of the grunfos soft start series it should start fine with a smaller generator.

More details needed....


It may be possible with a 1/2HP motor, but there are a lot of things working against you.

With a 250' well, he probably has a 3/4 or 1HP pump motor. The transformer is going to suck up some power, along with adding source impedance that the motor will see when it tries to start. I would have to think about it a little more, but I'm pretty sure it will make it more difficult for the motor to start. The length of wire from the breaker panel to the pump is going to be greater than 250' so you will lose a bit of voltage there too.

Finally I have had a bit of experience with inverter generators and they don't seem to handle big startup loads very well. I have tried using a 2000W generac inverter generator to power a small electric pressure washer with a current rating under 2000W and it wouldn't work. I think traditional generators do a bit better because the inertia of the engine and rotor spinning can help get you through a short current spike (even as they slow down some). With an inverter you are putting that load on a circuit board that doesn't have anything like that. Yes the board is driven by an engine, but if the circuit can't handle the spike then it doesn't matter.

In my opinion you should design your emergency equipment like the military does. If you need 5000W, your setup should should be able to supply it in the worst possible conditions, and do measurably better in ideal conditions. Unfortunately most of the consumer products out there (read generator power ratings) are the exact opposite. I know its not always an option for everybody, but it is a good goal to shoot for.
 
The EU2000 runs at about 1600 watts, but it will give 2KW for about 20 seconds IIRC for a motor start up

I can't think of any scenario where a single or paired EU2000i will have enough juice to power a 220 volt well pump even if you had a way to step up the voltage.
 
You assume that all well pumps are large and that's not the case in many areas. A smaller 1/2 hp motor is a tough load to start because you are pushing against a wall of water on startup but it's not what I would consider a huge load.

Many soft start systems in use don't have the big startup currents. A common configuration is the grunfos 3/4 hp SQ motor with a quality 2000 watt inverter.

People run their houses on 5000 watt generators with multiple loads. Slaved EU2000's produce over 30 amps. I would not be shocked to run a 3/4 hp motor using a step up trsnsformer with that setup.

I agree with the statements about step up xfmr's being a bit less efficient....it's not optimal it's done all the time.

We really need the OP's well/pump info....





The EU2000 runs at about 1600 watts, but it will give 2KW for about 20 seconds IIRC for a motor start up

I can't think of any scenario where a single or paired EU2000i will have enough juice to power a 220 volt well pump even if you had a way to step up the voltage.
 
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my advice to the OP, i would solicit the help of an expert, somewhere

near you, someone must sell and or install generators. do it right

do it once. also have them spec out what size you need.
 
No, its possible.

240V household power isn't really 2 phase, its 2 legs of the same phase. You would need a similar transformer to what is used on most utility poles, just with a different turns ratio.

Trust me, I'm an engineer.



You can get the voltage, but you won't have enough current from a 2000W generator. A 240VAC circuit at 25A is 6000W. Your 2000W generator can do 1/3 of that amount of power. Inserting a step up transformer is going to eat up some of that due to its inefficiency, so you will probably end up closer to 1200-1500W. You aren't going to start a submersible well pump with that.


The idea of having jugs of water has been brought up by some and dismissed by others in lieu of having a generator, but remember, if your well pump burns out (and they do on occasion) you will be out of water anyway.

Your house has incoming power at 240 volts AC. This 240 volts is measured line to line, between two incoming hot lines. These two lines are 120 volts each, exactly opposite each other, which makes 240 volts. There is a a neutral return that is grounded between the two. When you use either hot wire and the neutral you have 120 volts, which is what the bulk of household electric appliances and lights run on. . Coming from a single 110 line on a generator it would be very difficult and expensive to accomplish and would be cheaper to just buy the right generator for the job in the first place.
 
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During the ice storm of 08 and last years October snow storm, I was damn grateful my Generator was able to run the well pump. In 08 we didn't have power for a full week. I still had to get up and go to work every day, I wouldn't have been real happy if I went without a shower for a full week. I'll bet those around me wouldn't have been real happy either. For me being able to have heat and water was worth every cent.

No doubt. That's my justification too.

Are you on a multi-fuel unit or just gasoline?
 
I am an electrician. Please dont do this yourself... Hire an electrician and make sure you pull a permit. If your house burns down because of a "harry the homeowner" Installation your insurance wont pay you a dime. P.S. The battery/ Inverter idea is horrible!
 
Basicly, Dro527 is saying:

Das Machine is nicht fur gefingerpoken und mittengrabben. Ist easy schnappen der springenwerk, blowenfusen und poppencorken mit spitzensparken. Ist nicht fur gewerken by das dummkopfen. Das rubbernecken sightseeren musten keepen das cotten-pickenen hands in das pockets - relaxen und watchen das blinkenlights.


Source: http://www.annoyances.org/exec/show/article09-100 [laugh]
 
P.S. The battery/ Inverter idea is horrible!

If you could elaborate that would be nice. I understand it'll be expensive compared to just throwing a generator at it, but in a long term grid-down situation those components would be required in conjunction with solar panels.
 
I am an electrician. Please dont do this yourself... Hire an electrician and make sure you pull a permit. If your house burns down because of a "harry the homeowner" Installation your insurance wont pay you a dime. P.S. The battery/ Inverter idea is horrible!

I did not have any intention of wiring an inverter into the service panel. I was only pondering whether one generator/inverter could be connected to just the well, separate from the rest of the wiring. That's easy enough to do myself if the generator had the capability of powering the well pump; the only difficulty would be replacing the hard wiring of the well with a plug so it would be more convenient to switch to alternate power. And that isn't exactly rocket science.
 
We need to know what kind of pump you have. If there is a control box of some kind post a pic of the electrical label.

If you have a modern variable speed type its easily powered with a small generator. If its a classic old motor then it's not as easy....but not impossible. Your idea of installing a plug on the well is something commonly done on wells and furnaces in places where power goes out.

I did not have any intention of wiring an inverter into the service panel. I was only pondering whether one generator/inverter could be connected to just the well, separate from the rest of the wiring. That's easy enough to do myself if the generator had the capability of powering the well pump; the only difficulty would be replacing the hard wiring of the well with a plug so it would be more convenient to switch to alternate power. And that isn't exactly rocket science.
 
I'd like to tell you what kind of pump I have, but without pulling it out, I don't see any identifiable marks that would give me a hint. The pressure switch thingy looks old and unmarked, and I would guess has nothing to do with what type of well pump it is anyway.
 
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