240v Inverter questions..

S

Schaef

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So here's the scoop..

(Im based in the US)

I can purchase a 3000w inverter that outputs 120v for about $800
I can also purchase a 5000w inverter that outputs 240v single phase for about $800
240v to 120v 10,000w transformer = ~$200

Let's say I purchase the 5000w inverter.
I'll connect the inverter to grid via split phase 240v
I'll connect the 240v single phase output of the inverter to a 240v-120v transformer

Will I have a total of 10,000w of 120VAC power, because I stepped the voltage down? (with a transformer that can handle that much, of course)
(Obviously, this is before factoring in inefficiency and whatnot to the equation)

Is this as good as it seems in my head, or is there something fundamentally wrong that I'm missing entirely?

Thanks for your help!!

Schaef
 
No you will have 5000watts split between two 2500w legs- what ever loses your system has..
later floyd
 
From transformer perspective, you are not losing much. They are 99% efficient. What I saw in videos, there
are as well transformers in the US, which will create you a split phase system. So 240V in and 2x120V out. Half the
power on each leg of course. But if you are happy with all on one leg, then just go with the simple step down from
240V to 1x120V --> the wattage is same of the inverter of course primary 5000W/240V = 21A --> secondary 120Vx42A =5000W
 
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The transformer will just be a single phase I think - not split phase, but I suppose the answer is still the same.. my amperage increases, but total wattage stays the same.. thats why I was confused..

OffGridInTheCity - This is an off-grid inverter that you can bypass battery/solar for grid power if batteries are low/solar isn't keeping up. The inverter does not feed into the grid, though.

However, that does answer my question.. amps increases, watts stays the same.. Thanks!
 
Can the inverter take 2phase as input and not single phase 230vac? Make sure that... Many of the single phase 230VAC inverters require that you put in phase + neutral and not phase + phase!!!
This is important to check or else you need another transformer before it and you suddenly realizes its better to buy a proper unit :)
 
Daromer:

This is a pet peeve of mine. That many companies sell inverters designed for the European and other markets that show specs that they are 220-240v. Many say 50-60 hz. I don't know what the answer is to this coming question....what percentage of people in the USA know that Europe uses one leg to neutral and one leg hot at 230v, where we use 2 legs hot, normally interchangeable, and a neutral/ground wire in newer cases? I bought Victron, and many of the units for sale in the USA are not set up for our situation. Very confusing.

Also, I read up extensively about a year ago on transformers for split phase use. Victron goes into detail talking about how the current can be different on the phases, and that it is not always 50/50. I've already forgotten almost everything I read, so anyone concerned should just check it out on their own.

For the OP...it would be very helpful for you to specify what units you are looking at. Buyer beware....
 
Daromer - I had actually asked that question specifically of the inverter in question. It does in fact accept split phase 240v as input, and outputs single phase 240v. It has 220-230-240v selectable outputs, as well as a 50/60hz output.

I assume connecting 240v split phase vs connecting 240v single phase to a transformer isn't allowed..(outputting single phase 120v) I have to purchase either a transformer built for one or the other?

The 5000w Inverter - https://www.sigineer.com/product/50...220v-230v-240v-support-batteryless-operation/

The 3000w Inverter - https://www.sigineer.com/product/30...110v-120v-with-40a-utility-charger-50hz-60hz/
 
Came up with another question. Lets say I get the 5000w inverter. Its got a 10,000w surge for 3 seconds. The system will run 240v through the transformer to turn it into 120v. Is there usually a "surge" rating on transformers? Like.. If I get a 5000w transformer, does it have a surge rating of some sort, or is 5000w the max?

Also, should I be considering a autotransformer? That way, I'd get 240/120 split phase...
 
My 2 cents, get a transformer that is rated high enough to handle the surge. So if your surge is 10000w then get a 10000w (or higher) transformer. If you want splitphase then you need a transformer for that
 
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