Need 240 Volt Inverter Recommendation For Well Pump

Birdog

New Member
Hello all, new to forum. I have a 1250 sf cabin that is off the grid. I've been powering it with a Harbor Freight 7kw generator. We've had the place about 1.5 years. About a year ago we replaced the well pump and last week we fried the replacement. I just put in a new one. I bought a HF 7kw inverter generator but its throwing a switch when both window ac units are running and the well pump kicks on. And it kicks on every 3rd flush of the toilet. I'd like to convert the house to full solar this year but for now I'd like to put the well on batteries and keep the inverter generator so I'm pushing clean power to the house. I'd also like to switch from a pressure tank on the well to a 300 gallon storage tank with a 12 or 24v demand pump (similar to a boat sink pump) between the tank and the house to cut down on well pump on/offs. The well pump is a STA-RITE MSE 7. The tag says it pull 9.6 amps max at 230v.

Can ya'll weigh in and tell me if I'm on the right path? I'm not against buying the whole house controller now but think that may be overkill at this stage of the game. I'm thinking put in the storage tank and put the well on batteries and charge the batteries with a conventional battery charger plugged into the 120v or begin the acquisition of the solar panels.

Would also be interested in pump selection downstream of the storage tank.

¿Thoughts?
 

MichaelK

Photon Sorcerer
You have a garbage generator that's producing power so dirty that its already ruined two well pumps in less than 2 years. You should be expecting a well-pump to last at least a decade when supplied with proper power.

The answer is yes, of course solar can completely power your well-pump, and also your whole home, but not with the kind of junk you buy at Harbor Freight.

Your first job is to perform a power audit and determine how many watts you are consuming. For items that start under load, such as refrigerators, air conditioners, and pumps, you need to determine both the running power needs and also the startup power needs. The reason the generator pops the breaker when appliances are starting is because the startup surges are far higher than the running wattage. What you need to by is either a Kill-a-watt meter, or a electrician's clamp meter. The best choice is a clamp meter that has "inrush current" capability.

If you are used to paying Harbor Freight prices for equipment, then you really shouldn't expect solar to accomplish anything you want to accomplish. Good solar isn't cheap, and cheap solar isn't good. Expect to spend about 10k for a system of high enough quality to run your pump.
 

Birdog

New Member
Ok. Let's ty this again. And as Denzel said in Philadelphia, explain it to me like I'm 2 years old.

1. Can anybody recommend a good stand alone 24 volt to 240 volt inverter for a well pump?

2. Can anybody make a whole house recommendation on a solar system? Design criteria is 9,000 watts in a 1,250 sf house. I need:

- Solar panel recommendation. Solar panels will be ~150' from the controller.

- Controller. I am off grid. Ideally power to the controller will come from the solar panels but may also come from a generator.

- Batteries.

I'm a newby so if I'm missing something please feel free to add CONSTRUCTIVE advice. No more op eds or rants please.

Note that in my current situation, in a little more than a year, I've bought over 3,700 gallons of gasoline and logged over 9,000 hours of run time on noisy generators. So it's not like I'm on a budget. I'm looking for quality products so the generators can become a part of my past, not future.

Thank you in advance.

Bill
 
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MichaelK

Photon Sorcerer
How much money have you already spent replacing two well-pumps? I'm guessing it's in the 8-10k$ range? That money could have be used to create a stellar first tier system anyone could have been proud of.

My well-pump consumes about the same amount of power as yours, ~9.5A at 235VAC. I can power my pump from 8am to 4pm any day of the week on my home system.

My 48V home system consists of....
15 300W grid-tie panels
8 375Ah Trojan L-16 6V batteries
Midnight 200 charge controller
Schneider XW+6848 split-phase 120/240V inverter

My 24V workshop system consists of...
8 250W grid-tie panels
3 570Ah 8V Rolls batteries
Midnight 200 charge controller
Schneider Conext 4024 split-phase 120/240V inverter

I'm wiring 4 grid-tie panels in series for ~120VDC and run that about 135' with hardly any voltage drop. 150' is only slightly more, so wire at least 4 panels in series and that distance will be doable. Here's a pic of an array frame I built that now holds 4 panels. It could hold 6 panels, but at a different voltage. At 120VDC the voltage drop for 150' is right at 2%, which would be considered acceptable.

Running the wellpump is going to be easier with a 48V system. I would recommend skipping 24V and go straight to 48V. I always recommend having 2X panels for the load you run, so if you pump utilizes 2000W, have 4000W of panels. That would be 3-4 of my arrays, depending on the number of panels and how you wire them.
 

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Birdog

New Member
Wow. Thank you very much.

The well pump was more in the $800 each. The pump kicks off at 23.95 amps (230 volt) as runs at 10.15.

Questions:
- What well pump are you using and what depth is your well?
- Are you pumping into a pressure tank?

Thanks,

Bill
 

mike95490

Solar Enthusiast
You can build it cheap several times ( the path you are on) or you can build it properly, once.
You need a 48VDC system, 240VAC inverter for the pump (pure sine)
I started with 3,000 w of panels, which was ok in great conditions , adding another 2,000w array helped quite a bit.
Your inverter, batteries and DC wires HAVE to pass a huge amperage to get a 240V pump started. These AC motor specs are pretty much universal, My 1/2 hp 240VAC pump consumes 1,000w as logged by my inverter, even though "logic" says 1/2 hp is only 400w. But that's not real life with losses and other obscure electrical issues ( power factor )......

Well Pump Motor Specs.jpg
 

pvdude

Solar Enthusiast
I am working on finishing my first solar project to run the well pump here.
Bought one of these:

My well pump is a 1HP Goulds.
Runs at about 8 amps, but starting LRA (Locked Rotor Amps) is 41! (almost 10kw to start it)
The inverter is rated at 6800watts continuous, 8kw for 30 minutes, 12kw for 30 seconds, perfect for starting a pump.

Hope to finish installing it this month.
 

Steve_S

Offgrid Cabineer, N.E. Ontario, Canada
I use a Grundfos SQ-5 Deep Well Pump. It is a Soft-Start 120VAC Unit (aka Solar Friendly, no Surges) which starts at 550W and ramps to 1100W by the time it reached the 52PSI cutoff point. (Real Time Measured & Observed) The Pump is 260 feet deep, pushes to a 50 Gallon pressure tank and then 75' to house. You never ever notice the pressure drop or rise (marvelous when in a hot shower) and that is even with two filters, 1 large sediment filter & 1 fine filter in line.

LINK to SQ Family: https://product-selection.grundfos.com/products/sq?tab=products

GrundFos also has the SQ-Flex Family which can run AC or DC for those wishing to run their wells from direct DC.

PS, MichealK and others here DO KNOW THEIR STUFF yelping about rants etc... seriously ? check the tude or you'll be looking elsewhere for answers.
 

MichaelK

Photon Sorcerer
The well pump was more in the $800 each. The pump kicks off at 23.95 amps (230 volt) as runs at 10.15.

Questions:
- What well pump are you using and what depth is your well?
- Are you pumping into a pressure tank?

Thanks,

Bill
I'd say you are very lucky. My pump replacement years ago cost me 5K.

My pump is a 1hp Grunfos positioned at 380'. I don't use a pressure tank. I have a 5000 gallon storage tank situated about 150 vertical feet above my cabin. The pump delivers water from about 100 feet down to about 200' above. After the pump turns off, I have gravity feed that gives me about 75psi at the cabin. A one-way valve at the wellhead prevents water from draining past the cabin back into the well-bore.

Here are some important numbers to digest. When running the pump off an AC-Delco generator, the pump consumes 10.0-10.1A while running, and pumps 275gallons per hour. When powered by the inverter, the pump consumes 9.5A and pumps 305 gallons per hour. These numbers are averages over an 8 hour day. Same voltage for both.

The AC coming out of the inverter is cleaner than the generator, so the pump runs easier, with more water being pumped with less amp draw.

I would recommend the XW to anyone.
 

newbostonconst

Solar Addict
I also have a Grundfos SQ5 2-wire 1/2HP 137ft deep well. I run it off a Outback GS4048 inverter with a large house at the same time. The house usually uses just under 1kw consistently. Battery bank is 18 cell 280ah in parallel with 2 50ah battle born batteries.

Get a nice hybrid or off grid inverter that has a generator input so you can start the generator as needed. Then you can add to the system as you go.

You can even start with the inverter and cut the run time of the generator down. Charge for a few hours and then turn it off. Then add some solar to charge the batteries. Then add more battery.....work up on it.
 

Hedges

Photon Sorcerer
Is that 9000W peak, or 9000 Wh/day?

I like SMA. A bundle like this (contains two Sunny Island for 11.5 kW continuous, 22 kW surge) would make about 12 kWh/day


If expanding PV, I would use Sunny Boy AC coupled PV inverters (6 kW up to 24 kW of them) and over-panel 50%, with some panels oriented toward morning sun and some toward afternoon.

My own home system is like that, but rather than a trailer was individual inverters which I hung on the wall.
The trailer bundle is worthwhile if the forklift batteries it has are in good shape. Otherwise, buy two Sunny Island for about $2500 each.
 

ken morgan

Solar Enthusiast
Good Lord some of you are so full of yourself. treating people like that is a good way to get them to go to other forums there by hurting the forumowner who provides this little arena that you like to preen yourself in.

To the OP: Get a killowatt and do a power audit. there are threads that explain this. search: how to do a power audit?

Once you have those numbers you can move onto the next stage which would be asking for suggestions on an inverter to power what you have (or possibly what you plan to have if upgrades are on the horizon.)

From their would be determining size of battery bank to power (how many hours/days/?? without solar input or genset running.

Last would be size of PV array to charge said batteries. what time frame, location of array solar inclination etc.
 

Just John

Photon Sorcerer
Good Lord some of you are so full of yourself. treating people like that is a good way to get them to go to other forums there by hurting the forumowner who provides this little arena that you like to preen yourself in.

To the OP: Get a killowatt and do a power audit. there are threads that explain this. search: how to do a power audit?

Once you have those numbers you can move onto the next stage which would be asking for suggestions on an inverter to power what you have (or possibly what you plan to have if upgrades are on the horizon.)

From their would be determining size of battery bank to power (how many hours/days/?? without solar input or genset running.

Last would be size of PV array to charge said batteries. what time frame, location of array solar inclination etc.
I can tell you, if his generator is a modified sine wave, a Kill-a-Watt meter won't last very long. Anything with an electric motor, you can hear the difference, and it likely will contribute to an early pump death. Harbor Freight is not exactly known for top of the line products. The "normal" Kill-a-Watt meter also won't retain the consumption data when it is unplugged (or the generator is turned off). They are great for seeing how much energy your refrigerator uses in a month, but get the more expensive version with non-volatile memory.

Since he is running everything off a generator, he might already have a good idea of his power consumption, if not, he should start with the audit as you suggested.

I suggest that he might look at some all in one units from Growatt or MPP, and get two for the split phase. That also gives him two solar charge controllers to start adding panels, plus the ability to charge batteries using the generator. Starting from scratch with a solar system means don't use 12v, 24v and 48v are much better options.

Two SCC also means that he can do as someone suggested and have an east array and a west array to get more out of the morning and evening sun.

Batteries, there are many choices/options, but in the long run lead acid is more expensive.
 

ken morgan

Solar Enthusiast
I can tell you, if his generator is a modified sine wave, a Kill-a-Watt meter won't last very long. Anything with an electric motor, you can hear the difference, and it likely will contribute to an early pump death. Harbor Freight is not exactly known for top of the line products. The "normal" Kill-a-Watt meter also won't retain the consumption data when it is unplugged (or the generator is turned off). They are great for seeing how much energy your refrigerator uses in a month, but get the more expensive version with non-volatile memory.

Since he is running everything off a generator, he might already have a good idea of his power consumption, if not, he should start with the audit as you suggested.

I suggest that he might look at some all in one units from Growatt or MPP, and get two for the split phase. That also gives him two solar charge controllers to start adding panels, plus the ability to charge batteries using the generator. Starting from scratch with a solar system means don't use 12v, 24v and 48v are much better options.

Two SCC also means that he can do as someone suggested and have an east array and a west array to get more out of the morning and evening sun.

Batteries, there are many choices/options, but in the long run lead acid is more expensive.
and that is kind of how we should all approach helping each other, with measured words of experience without all the snark that some of the other members put out.
 

Just John

Photon Sorcerer
and that is kind of how we should all approach helping each other, with measured words of experience without all the snark that some of the other members put out.
I'm just as guilty, it is difficult to communicate sometimes with only the written word.
It's just as likely the intention was not snarky, it just came out that way. Very difficult to judge your own writing.

Inflection, tone, and even facial expressions go a long way to how things are perceived.
 

ken morgan

Solar Enthusiast
I'm just as guilty, it is difficult to communicate sometimes with only the written word.
It's just as likely the intention was not snarky, it just came out that way. Very difficult to judge your own writing.

Inflection, tone, and even facial expressions go a long way to how things are perceived.
True that true that, I find the same thing even when dealing with Japanese on the phone, even though i speak Japanese quite well when I can't see the face to gather extra quantifiers it get tough at times.
 

ken morgan

Solar Enthusiast
Snark or general Bullshitting between friends or acquaintances is acceptable. EG: I have a forum i go on where every other pst is an insult to someone's mother or wife...but we have been on the same forum for over a decade so its cool we all know each other. newbs come we tone it down and let them know that after a time the gloves come off.. when they get some salt on their collar.
 
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Just John

Photon Sorcerer
Just wanted to add, I've had success measuring surge startup with this meter (for a reasonable price):


To measure you need to only clamp one side of the AC line, so this helps:

 
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