220v system

[GuyMitts]

Hi, as I am looking to set up a very simple solar power set up I have run across a small question.

I want to set up solar power to my Water Pump House. Here is what it has.
1 Well pump - 3/4hp, 220v, turns on when needed, about 2 times per day, 5 minutes each.
1 water conditioner, 110v, turns on about 1time every 3 days, 2hr on time
2 outlets, when needed, very very seldom, like 1 or 2 times per year.

I have a 12v/110v 1000watt inverter used elsewhere, but it can be used here.
Here is my question, should I buy an additional 12v/110v 1000w inverter or
should I buy a 12v/220v 2000w inverter.?

Here is an additional question, will the newer 220v box (if that is what is recommended) comes with a single 220v line or two 110v lines in the plug?

Additional information: My well (water pump) is hard wired it the breaker box so I will be connecting the solar power system to the breaker box.
I Have a budget of 750-800 dollars for this project.
This will be off-grid

 

[Bud Martin]

Are you in the USA?
How is the 220VAC pump getting the power right now, from utility?
If you want to use inverter for the 220VAC pump, then you need to by 220V output inverter, I cannot see how buying another 120VAC inverter will solve the need of 220VAC power source to run the 220VAC pump.
BTW, do you have the full spec of the 220VAC pump? Because you need to find out what the startup surge is so you can get the inverter that can handle it.

 

[pollenface]

The well pump will likely need an inverter with a surge capacity 5-7 times the pumps continuous power needs to account for inrush current during startup. I think you may be looking at $800+ just for the inverter.

Two 110v inverters will not make 220v, they will not synchronise and blow each other up.

 

[GuyMitts]

Are you in the USA?
How is the 220VAC pump getting the power right now, from utility?
If you want to use inverter for the 220VAC pump, then you need to by 220V output inverter, I cannot see how buying another 120VAC inverter will solve the need of 220VAC power source to run the 220VAC pump.
BTW, do you have the full spec of the 220VAC pump? Because you need to find out what the startup surge is so you can get the inverter that can handle it.

The current power supply is PGE, local power company. I live outside the Portland OR area, on an Island, When the power goes out for 200 of us, and there are 1000's more inside the city, you can guess who is going to get priority. We seen to be the last ones to get our power back on. 7-9 day without power is a long time.

I don't have the specs on the pump surge capacity. The company that installed it for me is no longer there. All I remember is that it has 3/4 hp. It is also on a 20Amp breaker.

 

[GuyMitts]

The well pump will likely need an inverter with a surge capacity 5-7 times the pumps continuous power needs to account for inrush current during startup. I think you may be looking at $800+ just for the inverter.

Two 110v inverters will not make 220v, they will not synchronise and blow each other up.

Well, I haven't heard of the 5-7 times the pumps continuous power. 2-3 times is what I've heard. I'll look into it.

The requirement for the one 220v inverter needs looking into.

thanks

 

[chrisski]

Here is an additional question, will the newer 220v box (if that is what is recommended) comes with a single 220v line or two 110v lines in the plug?

I have only started looking at 220 V inverters and have not found that option.

That is similar to an RV 50 amp jack that has two 120 volt inputs that typically are wired to one to one set of breakers, and the other to a different set of breakers, but can be combined to a single 240 volt Iine,

I would be interested if that exists.

A decent inverter will tell you in the manual what you can expect for different notes surge wise. SInce you have to buy it to see if it really works, its also nice if whatever you decide on can be stacked in parallel with another.

 

[Bud Martin]

You can buy 240VAC 60Hz single phase inverter, or you can buy 240V split phase (120V-0-120V) inverter.
240VAC 60Hz: example

Aims Power PWRINV5K24012W 5000 Watt 240Vac 60hz Power Inverter New

Aims Power PWRINV5K24012W 5000 Watt 240Vac 60hzPower Inverter New. 1 year warranty. Direct from Manufacturer.

factorypure.com

Split phase:

120 240V Split Phase Inverter Chargers Archives

Split Phase Inverter Charger outputs 120/240v power supply which is split compared to 230V L N single phase system. Inverter capacity from 3000W 6000W 12KW 15,000w 18000 watts. Pure Sine Wave Output, 120 240V 110/220V 208V adjustable. Battery DC voltage from 12V 24V 48V to 96V. Models w/ builtin...

www.sigineer.com

 

[Hedges]

Expect surge current to be 5x the current rating on the motor label. Usually only lasts a fraction of a second.

Running only 10 minutes per day. Pump is much larger than really needed.
Is this a well pump? Down in the hole, or on the surface?
If not a well pump, just a transfer or booster pump, there are low power alternatives.
Shallow pump on the surface, again alternatives.
Deep well pump, the alternatives aren't economical, so suitable inverter would be the way to go.

Generator to run pump and larger tank so only used once a week might be an alternative.

 

[TorC]

If your usage on the pump is really that low, you can probably switch to 1/2HP or smaller pump. That will make things easier on the inverter, although a 3/4HP isn't hard to run on a decent inverter. Unless you're just running a sink, toilet, and brief shower for a couple people in a cabin I'm a bit doubtful your runtime on a pump like that is really that low.

Do you have any specs on well depth, static water level, and production capacity? The static water level in particular will be needed if you decide to change your pump.

Here is the spec sheet for Franklin single phase motors: https://franklinwater.com/media/124017/Page-13.pdf Should be pretty much standard for any mfr., so you've probably got a 35-40A Locked Rotor startup surge. That's well within doable.

What's the power draw on the water conditioner?

For as little use as you have, and only for larger devices, you can probably use the search mode of the inverter minimize draw, or perhaps even a precharge with DC contactor to run the inverter, and another contactor on the inverter output for actual pump control. Same for water softener. Just a potential optimization to put in the back of your mind for now.

 

[TorC]

This is one inverter worth considering: https://www.donrowe.com/Magnum-Energy-MS4448PAE-p/ms4448pae.htm

I was looking at it for another system, but it doesn't have some features I wanted, but it was *very* tempting otherwise. Could be right at the edge of starting your pump if it's a 2-wire, but if you've got a 3-wire it should have no trouble at all. Even the inverting no load is very nice.

If you're up for completely changing, this thread has info I'm investigating now for a well: https://diysolarforum.com/threads/t...phase-ac-pumps-for-solar-water-pumping.22876/

As for your total usage, going off-grid should be easy. To use pessimistic specs, 6.8A full load at 240V, that's 1632VA. Call it 1632W for convenience. At 1/2hr runtime per day, that's ~.8kWh. Worst case inverter idle inverting is .6kWh for 1.4kWh/day. To give yourself a 3 day zero input buffer with 80% DoD cutoff, that's a 110Ah 48V LFP bank for the pump alone. That's not terribly expensive. Add in the conditioner, ideally measured through a run cycle with a Kill-A-Watt. Figure half a cycle daily to ensure you won't run short.

For panels, I'm not sure what minimum reasonably likely daily output is where you are. Might be in the neighborhood of 1-1½hrs/day nameplate. A battery system like above can go a long time with input a bit under daily usage, however. Depending on the conditioner, 1kW nameplate will probably mean you'll almost never to never need a generator.

Tools on occasion can be ignored unless it's probable you'll be running them in the middle of the worst conditions of the year.

 

[GuyMitts]

Expect surge current to be 5x the current rating on the motor label. Usually only lasts a fraction of a second.

Running only 10 minutes per day. Pump is much larger than really needed.
Is this a well pump? Down in the hole, or on the surface?
If not a well pump, just a transfer or booster pump, there are low power alternatives.
Shallow pump on the surface, again alternatives.
Deep well pump, the alternatives aren't economical, so suitable inverter would be the way to go.

Generator to run pump and larger tank so only used once a week might be an alternative.

Yes, it is a well pump. Down the hole. It kicks on and fills my water tank. About 10 minutes. The water tank provides water for the house. That's the way its been for almost 30 years.