Three phase generation, needing only split phase...

Thread Starter


Joined Nov 29, 2005
Hello all.
Am very tempted to buy a unit that generates 40KW on 480VAC 60 Hz 3phase. (I do not know if it is star or delta). My needs are just 240VAC split phase under 12KW :rolleyes:
Is there a way to transform/modify the power outputted ?


Joined Jan 23, 2018
Three-phase power can have the voltage changed using three single phase transformers, which for a given power level will probably cost less than a single three phase transformer. But I am not aware of a simple way to efficiently convert the total 3-phase power to the same total single phase power. Certainly it can be done but it is neither simple nor cheap.


Joined Nov 22, 2017
My needs are just 240VAC split phase under 12KW :rolleyes:
Is there a way to transform/modify the power outputted ?
Three to single-phase transformers have a three-phase input and a single-phase output.
They are particularly handy when it is necessary to power a big single-phase load but only a three-phase system is available. The three to single-phase transformer allows an excellent distribution of the power absorbed by a single-phase load on all three phases.
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Joined Mar 14, 2008
Do you need the 240V split-phase to get both 120V and 240V?

You could use one single split-phase 240V-120V output transformer connected to one of the generator's three phase outputs.
You should be able to draw at least 10kW from the one phase.


Joined Jul 18, 2013
Very simple, I have implemented it a few times, all a 3ph transformer is, is 3 single phase transformers mounted on the same frame.
There is no perceivable difference.


Joined Jan 23, 2018
A scheme not mentioned would be to feed the 480 volts/3phase into a full wave rectifier and the use an inverter to provide the desired 240 volt output. That would allow the alternator to deliver it's rated output under the most favorable conditions, It might possibly also be the most efficient, and certainly the inverter output transformer could provide whatever voltage and frequency was chosen. Of course, a 12 KW inverter with a 3phase 480 volt input is not a simple thing.