Is 240v really necessary?

[S610]

After having learned that many systems do not provide 240v, and adding it would be pricey I don't think it is required. No central a/c, electric stove, dryer, or big power tools. I thought the well pump may require it but it appears they even make deep well Grundfos pumps and electric lawn mowers that work on 120v.

Am i missing something?

 

[Q-Dog]

Higher voltage means lower amperage. But, if you don't have 240 loads you don't need a 240 system.

 

[pvgirl]

Well pump and heat pump/ac are the common requirements for 240 volts, but if you don't have those or are able to 120 volt versions you don't need a 240 volt system.

 

[jimf909]

No, as pointed out above. I never missed 240 but situations are different for different people.

 

[S610]

Well pump and heat pump/ac are the common requirements for 240 volts, but if you don't have those or are able to 120 volt versions you don't need a 240 volt system.

I thought I would need it for the well pump but it seems Grundfos has other options though it may depend on well depth.

 

[OffGridForGood]

120v pumps are available but will be double the amperage of similar 240v pump of same output.
Higher amperage = larger ga. wire.
So you may be buying larger ga. wire to feed a 120v pump. (cost more).
That said, you only buy the well pump wire once!

 

[S610]

120v pumps are available but will be double the amperage of similar 240v pump of same output.
Higher amperage = larger ga. wire.
So you may be buying larger ga. wire to feed a 120v pump. (cost more).
That said, you only buy the well pump wire once!

I will make a note of that! Heavy wire may cost more but probably not as much as another 3 grand inverter.

 

[OffGridForGood]

I will make a note of that! Heavy wire may cost more but probably not as much as another 3 grand inverter.

LOL - I expect so!

My own well pump is 120v which is not ideal in my case because I run a 120 /240 system best when L1 and L2 are balanced loads. It is impossible to balance the other leg of a high load like a well pump, that will cycle at radom times during the day. A 240v pump would keep equal load on both legs.
That said, I am not pulling a perfectly good deep well pump just to change it's voltage, LOL, one day this pump will need to be replaced, and 240 will be my solution, until then it runs fine (with enough battery and inverter to support it) so it can stay as is.

 

[12VoltInstalls]

240 split phase is useful- when you need it.

I run on a 12V 2kW inverter and it does every household thing I need it to.

What it doesn’t do is run my TiG or the bigger power tools. Nevertheless, when I upgrade to run the TiG on solar power instead of generator I’m not replacing the current system: I will create a second system to run the shop tools.

So many times opinions of what people need are not what they need. What they need is for stuff to just work.

 

[rhino]

120v pumps are available but will be double the amperage of similar 240v pump of same output.
Higher amperage = larger ga. wire.
So you may be buying larger ga. wire to feed a 120v pump. (cost more).
That said, you only buy the well pump wire once!

I switched my inefficient high surge 240V well pump for a 120V grundfos and never had issues. The wiring did not have to change since it is still only about 6A when running with no surge.

 

[S610]

I switched my inefficient high surge 240V well pump for a 120V grundfos and never had issues. The wiring did not have to change since it is still only about 6A when running with no surge.

Did you have to add a soft starter to it? Which one did you get?

 

[rhino]

Did you have to add a soft starter to it? Which one did you get?

All of the Grundfos are "soft start", they don't need anything extra. With my old 240V pump that it replaced you could always tell when it came on because the lights flickered from the high surge. With the Grundfos you'd never know.

 

[Rednecktek]

When mine dies I'll be willing to spend the $1600+pipe+wire+fittings, but until then let the lights dim in the pump house. ?

 

[Vigo]

Just to point out about the 120/240 split phase balancing issue.. if you run ONLY a 120v system there is nothing to be concerned about there since the only balancing getting done will be between parallel inverters (if you run more than one) and they figure that out automatically between the two of them.

I have a 120/240 split phase system with an autotransformer (no grid connection) but i have repeatedly considered just getting a separate 120v inverter. The main reason why you perhaps wouldn't do that is if you have devices that use BOTH 120 and 240, which unfortunately is common with large appliances like oven/range combos, washer/drier combos etc. My system works fine as it is, but there are definitely a bunch of design considerations you just wouldn't have to account for if you run a 120-only system.

 

[Supervstech]

If ya need it ya need it.
I dont think I would buy a 1500.00 120V well pump to replace a 240 one, just to avoid buying a 3000.00 inverter that would provide more options if I need some MORE POWA!

 

[OffGridForGood]

The solar enthusiast's trap:
I just need to add one more (battery/Inverter/PV array) and yup I will be all set...add some new loads, and repeat.

I believe I started with an idea to have some batteries and inverter to run shop lights during (frequent) power outages...since standing in the dark, and pulling out the honda was not that convenient...somehow that road led to this whole "on-site-power-plant" that kinda grew up from the original vague plan...thanks to all your help guys!

 

[HarryN]

I can't speak for your application - but for my grid connected home, my biggest regret electrically is not having 3 phase.

There are so many neat used wood and metal tools that can be purchased at low cost because they are 3 phase and most home owners just can't easily power them.

Yes I know that there are ways around this, but just pointing out that if I went though the bother of going off grid, I would either go 120 vac single phase or just go full 3 phase vs goofing around with split phase.

 

[MichaelK]

Most of the split-phase 120/240V units are higher end products, so just buying anything that puts out 240V means you are getting a higher quality product.

 

[OffGridForGood]

I can't speak for your application - but for my grid connected home, my biggest regret electrically is not having 3 phase.

Actually, if I configure it, my three MPP 6048's can output three phase 120/208.
The bigger machines in the shop already had VFD's on them since no 3-phase was available from the utility, I just kept those rather than building a 3-phase system, which would then require me to balance that 3-phase power, ah, no thanks!

 

[OM617YOTA]

I went with split phase 240v because that was the easiest way to integrate into my home wiring and 240v well pump.

I need to try my welder on solar produced 240v.