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Running a three-phase asynchronous motor in single-phase?

published: 13/04/21, 21:19
by idy
Is it possible to run a 600W 50Hz asynchronous motor with a 12v 75am battery and 1000w inverter (DC / AC) if possible for how long?

Re: Bjr is it can run a three-phase asynchronous motor (torque with a capacitor to convert it to monoph

published: 13/04/21, 22:10
by Obamot
In theory, we can get out of this by using a specific assembly to transform the three-phase current into single-phase and vice versa (eg: with a capacitor, a frequency converter, etc.).

Example: once I sold an offset machine and the guy paid cash. Shortly afterwards the guy who could not install three-phase (because of the owner) was confronted with this problem, but as far as I can remember he had to change the motor ... It was a small A3 offset machine, so that was going to...

There is a more serious problem, which is whether the 250V will suffice for your needs. In my example that was enough ...

Three-phase motors are readily 400V ... but there is a better efficiency.
If you really need a lot of power, single phase may not be enough. Or it will not be possible to make an assembly that holds up.

It is still possible to change the power supply to your electricity supplier.

Re: Bjr is it can run a three-phase asynchronous motor (torque with a capacitor to convert it to monoph

published: 13/04/21, 23:11
by izentrop
Hello, for the engine it is possible with a loss of 1/3 in power.
For the calculation of the capacitor http://www.volta-electricite.info/articles.php?pg=2000

On the other hand for the inverter it will take at least a 6 kVA if not it will cut out before the motor starts.

Re: Running a three-phase asynchronous motor in single-phase?

published: 13/04/21, 23:23
by idy
Good the mechanical power developed by the engine is just to have a torque of about 1N / m

Re: Running a three-phase asynchronous motor in single-phase?

published: 13/04/21, 23:26
by idy
That is to say, the inverter will not be able to hold out to run the motor. : Idea:

Re: Running a three-phase asynchronous motor in single-phase?

published: 14/04/21, 00:16
by izentrop
It is necessary to count a starting current 10 times the nominal current. 6 kVA is for a low-end inverter. If in the characteristics of the inverter it is indicated that it can withstand a starting current of 10 X without tripping, why not. You have to be on the move.
For example, I tested a 3 kVA converter on a freezer with a measured 150 W motor ... starting impossible. Well in general these engines start under full load.