I want to power my 1 HP well pump that is U.S. 240v split phase from a small solar system.

[Savage]

I have a 240v well and I occasional have extended power outages. I want to hook up an inexpensive 3000w (6000 surge) US 240 split phase inverter or a 120v to a US split phase 240v voltage converter/transformer to an existing small backup solar system. The budget is $500 or I just will buy a small backup generator to run the pump. I already bought A 110/220 converter but it turned out to be for the European 220 single phase, as is every one I find on Amazon.

 

[Craig]

I do not think it can be done with reliable products for $500
lead acid rv battery $110
SCC $100
inverter 300
Panels 120
plus wire and fuses
this would be a bare minimum system and Im not sure how long battery would run for.

 

[Savage]

I do not think it can be done with reliable products for $500
lead acid rv battery $110
SCC $100
inverter 300
Panels 120
plus wire and fuses
this would be a bare minimum system and Im not sure how long battery would run for.

The small solar system is already set up, $500 to convert 12v DC or 120v AC into 240v split phase AC using an inverter or converter/transformer.

 

[indianajonze]

Any luck with this? I too would like to occasionally run my 240v well pump from my solar inverter, ideally connected to my 120/240v 30 amp manual transfer switch with a L14-30p NEMA input

 

[Savage]

Nothing yet.

 

[Steve_S]

12VDC to 240 VAC Split Phase 60hz will be very hard to find, most use 24VDC to get there. A quick search shows Pure Sine 24vdc-240VAC Inverter/Chargers running around 1100-2500 USD, the $1100 being lower end High Frequency inverters (not best for motors / pumps, ok for electronics only) whereas a Low Frequency PureSine will handle everything and take 3X the surge for starts (HF typically max out at 2x surge capacity).

I have a Yiyen (an OEM) APC-Combi 3024 Inverter/Charger (secondary system) which is not feature rich and fairly basic but works very well and they sell for $650 ish USD and they make 240 Split Phase 60hz models, some with ETL, UL & CSA certifications as well. REF: https://www.alibaba.com/showroom/yiyen-inverter.html

Another brand OEM is sigineer who also have a 12VDC to 120/240 60hxz split phase inverter. I have not used Sigineer myself but know a couple of fellows that do and they love'm and you really can't beat the price. REF: https://www.sigineer.com/product/30...0vac-double-phase-pure-sine-inverter-charger/

 

[Supervstech]

Knowing the running, and starting amps will help here.
if ALL you are running is the pump, the inverter doesn’t have to be split phase. A true 230v inverter will work, but the frequency needs to match, so 60hz. The low cost inverters should operate the pump, but the running rating needs to be able to handle the startup under pressure... most are 20amp pumps, and will pull 60 amps or more on startup. Try getting the specs for the pump, and source an inverter that can output the amps.

 

[Supervstech]

If the pump operates with a 15amp running load, a 5000 watt with 20second surge is going to be needed to start the pump.
if it only pulls 8amps running, then maybe a 3000watt inverter will power it... find out.

 

[Savage]

It’s a 1 HP motor so that should be around 8 amp @ 230v.

 

[offgriddle]

The question is not if solar equipment is available to power this for it certainly is, the question is how many amp hours in a typical 24 hour period do you require to operate your 8 amp per hour device?

 

[offgriddle]

Don't forget, your well pump will need three to five times the rated wattage to start the pump. P = 8 amps x 220 volts. So your invertor will have to produce 1760 watts to run, BUT, three to five times that wattage to start.

 

[Mars]

I was thinking about a similar setup (running a 240VAC load using a 120VAC inverter) and came to the conclusion that using an autotransformer connected transformer was the best solution. I found suitable transformers on ebay for about $50-90.

 

[Savage]

The question is not if solar equipment is available to power this for it certainly is, the question is how many amp hours in a typical 24 hour period do you require to operate your 8 amp per hour device?

15 minutes a day.

 

[Steve_S]

FYI for anyone looking to buy a Water Pump while being solar powered / battery powered.

Soft Start Pumps are really the only solution for anyone using Solar Power & Batteries. My own Grundfos SQ5 is a soft start 120V deep well pump, 260' deep, -> 50 Gal pressure tank -> 75' to cabin @45 PSI you never feel a drop in pressure. It starts at 550W and increments by 100W till it peaks at 1000W when reaching max pressure. NO big surges or hits and Very Inverter Friendly.

REF: https://us.grundfos.com/products/find-product/sq.html

 

[Supervstech]

15 minutes a day.

This should be easily handled by a single battery, and an inverter able to handle the startup amps. Figure 28 amps startup. A good 2000 watt inverter with low frequency surge would handle 6000watts. Or a cheaper 4000 watt with 8000watt surge should hold it.
And a 100 watt panel should be able to recharge the battery in most daylight conditions.

Why do you only need to run the pump 15minutes a day?

 

[Supervstech]

Hi, i am looking for a similar gadget, what is the exact name of that "autotransformer" ?

Thanks

It would technically be a step-up transformer.

 

[Supervstech]

Ok, what i find is that the great majority are for European usage, a European 220/230v is significantly different from South/North America.

A transformer doesn’t care where it is used...
If it is a 2:1 transformer, rated for the current you need to produce it will work in either direction... AC power is great that way.
A 2000 watt transformer that can step down 480v to 230v, will step up 120v to 240v... most will state this on the data plate...

 

[Supervstech]

Ok, what i find is that the great majority are for European usage, a European 220/230v is significantly different from South/North America.

Keep in mind... you canONLY power 240v devices with the step up... it will NOT give you split phase...

 

[Supervstech]

Any of the step up transformers rated for the wattage your well pump need will work. FOR THE PUMP. Not to feed a mains panel with 120 and 240v circuits.

 

[Mars]

Hi, i am looking for a similar gadget ( one that can take 2-120v and up it to 240v) what is the exact name of that "autotransformer"?

An autotransformer is just a transformer. What makes it an autotransformer is the way you connect it. An autotransformer has the primary and secondary windings connected together. Here is a video that helps explain the connection:

In this video they are boosting 120V to 600V. If the second winding were to be 120V instead of 480V they would get 240V out.

You could use any transformer that has either a 120x240V or a 120/240V winding.

Mars