# A thought about getting around a new 3 phase installation.



## wiz1997 (Mar 30, 2021)

Just about all the machines I currently work on were built in Holland.
They are all supplied with 240 volt, single phase, but all have 3 phase motors.
Our VFD's are 240 volt, single phase input, three phase output.
So the answer to the question is Yes it can be done, very easily. 
We use Siemens Micromaster 420 with various kW ratings.
The size of the VFD will depend on the kW or horsepower of the motor.
I've also used Allen Bradley, Danfoss, and several off the wall brands.
Make sure when you order whatever brand and size you decide on, that you specify 240 volt single phase input.
The question is does the entire machine need 3 phase or just the motors?
Getting in contact with the manufacturer for their suggestions might be the way to go before you do the wrong thing and void the warrenty.


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## oldsparky52 (Feb 25, 2020)

wiz1997 said:


> Getting in contact with the manufacturer for their suggestions might be the way to go before you do the wrong thing and void the warrenty.


IMO this is the first step.


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## SWDweller (Dec 9, 2020)

I have done the single to 3phase with a VFD countless times. Only really works for motors. You have to add a transformer if you have any electric heaters in the circuit. That is 50% of you issue. As for the 50 hz I am not so sure about that. While you contacting the mfg you best be calling the mfg for the drive. Thinking out loud at 50hz your going to be in a low voltage condition.


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## mofos be cray (Nov 14, 2016)

I believe a vfd should be able to do it. To switch to 3 phase from single phase you double the hp rating of the drive. A vfd will should give you any frequency you want.
also I don't know the rules in the states but in Canada if the power were metered separately then you could not bring the second feed into the building.
They want one main disconnect that would shut off power to the building.


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## MotoGP1199 (Aug 11, 2014)

Lock said:


> Ok so a building in the company im working for wants to use a new machine from out of the country. I'm in US. So We have 240v single phase there and the machine is 3.6kva, 220v, three phase, at 50Hz. So I was thinking of running wires from our neighboring building underground that has 3 phase and intalling a frequency converter to get the power from 60 to 50 Hz. BUT! i just thought of this while repairing another machine. Is it possible to run a machine off of a VFD? (The machine has PLC and many little servo motors.) Ok so if I'd put in the 1ph, 240v, 20A, 60Hz input drive could I then program the output of the drive to 3ph, 220v, 20a, 50hz? does this seem like it'd work? I have never tried to power a complex machine with a VFD. Let me know if anyone has tried it and know that it works.
> 
> THANKS IN ADVANCE!



If its an entire machine needing 3 phase then look into getting a rotary phase converter. If its just a single motor a VFD is all you need. 



wiz1997 said:


> Just about all the machines I currently work on were built in Holland.
> They are all supplied with 240 volt, single phase, but all have 3 phase motors.
> Our VFD's are 240 volt, single phase input, three phase output.
> So the answer to the question is Yes it can be done, very easily.
> We use Siemens Micromaster 420 with various kW ratings.



Are you saying your using a VFD for the entire machine or just the motors? Also is the rest of the equipment 50hz, 60 hz or 50/60hz, just curious?


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## wiz1997 (Mar 30, 2021)

MotoGP1199 said:


> If its an entire machine needing 3 phase then look into getting a rotary phase converter. If its just a single motor a VFD is all you need.
> 
> 
> 
> ...


We are using the VFD's for just the motors. 
Most of the rest of the equipment, contactors, PLC's, temperature controllers, level sensors, and a few other devices are all 24 VDC, so frequency doesn't matter.


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## JRaef (Mar 23, 2009)

Lock said:


> Ok so a building in the company im working for wants to use a new machine from out of the country. I'm in US. So We have 240v single phase there and the machine is 3.6kva, 220v, three phase, at 50Hz. So I was thinking of running wires from our neighboring building underground that has 3 phase and intalling a frequency converter to get the power from 60 to 50 Hz. BUT! i just thought of this while repairing another machine. Is it possible to run a machine off of a VFD? (The machine has PLC and many little servo motors.) Ok so if I'd put in the 1ph, 240v, 20A, 60Hz input drive could I then program the output of the drive to 3ph, 220v, 20a, 50hz? does this seem like it'd work? I have never tried to power a complex machine with a VFD. Let me know if anyone has tried it and know that it works.
> 
> THANKS IN ADVANCE!


it's not a good idea to feed electronics with the output of a VFD, the VFD output is intended to be used on an induction motor, not another power supply. 

But, your servos are all going to have the equivalent of a VFD on them anyway, in fact I would bet that the smaller ones are using a single phase input anyway. What you really need is a wiring diagram for the mach9ine and determine if 3 phase is even needed for anything.


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