Using a 110 to 220 step up converter

Hi, have an off-grid 110 volt solar system. Need to add a well pump to the system (previously gravity fed surface water). Problem is that the well head is 120 feet from the house (septic system set back requirements) and about 230 feet deep (with about 40 feet to the top of the water). Plan is to place the pump at about 210 feet. But that gives a run of at least 330 feet and the pump installer is figuring a 3/4 hp pump. Likely a Grundfos 5SQ07-270. Because it has built in soft-start, we are hoping to avoid the usual motor start up surge. But still, that's 600 watts. At 330 feet I'm not sure what wiring to run. I've done the calculations and it should be able to handle 12/3wg the whole distance. Just don't want to get caught having to move up to 10/3 for the higher amps over that distance. Luckily the pump has a wide voltage range so It should be able to handle even a 20 volt drop at 220. Any thoughts? Go with the 110 volt without a step up converter? or go with the 220 with a step up converter. And do the step up converters use power when not in use? couldn't find an answer to that.
Thanks.
Thanks.
Comments
I also found if the autoformer is turned on with the pump pressure switch closed, the gfi opens, but if the autoformer is powered first, no problem. A well pump likely wouldn't have gfi though, so likely not an issue.
Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-Lister ,
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-Lister ,
Just guessing though. My 1/2 hp pump is an energy hog at 100'. And 12 AWG was barely enough - voltage sinks to ~108 under use.
I'm not sure what gensets do to make 220 volts. That may yield the answer.
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-Lister ,
Highly simplified becaause thats how I roll.
My X240 can step up from 120v source to 240v load (which I do to run a pump), or step down from 240v source to 120v load.
Step down might be used, for example, on a split phase 120/240v generator to load balance L1/L2 where a big 120v load taken directly off one leg can cause issues for the genny.
Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
or no step at all, but simply for load balance, because many 240VAC inverters need balanced loading to operate most efficiently.
I am using the 240V windings only.
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-Lister ,
120 in one leg?
So to do this, you really need to understand how transformers and electricity work and should be wired. Make a mistake, and you will be looking at the charred stump where your hand was.
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-Lister ,
But I'd avoid the issue and use a 115V well pump. No need for 3/4 HP when water is at 40' (+ draw down).
12 gauge copper is fine for the Grundfos 5SQ07-270 (8.4 amps, 2000 watts).
I am available for custom hardware/firmware development
Pump is set at 120', but water depth is about 35' below the pressure tank, and I run low PSI in the systems, so pumping head is low.
Neat use of the secondary windings to make an autotransformer Mike.