Using triphased motor on single phased motor capacitor specification diagram 1

[cuchara]

Hello everyone!

I'am new here, trying to find the way to use a three-phase 380 Volts motor in single-phase 230V
I spent sooo much time looking for answers but the only things I've found are more questions.

So making the question simple, I have these 3 motors:

and I need to use them with 230v single phase, witch capacitor do I need for each one, and how do I have to connect them?




Please don't tell me to go to search in google, I've already did that and I have so many questions now. Because I don't find what I need precisely for these type of motors.

The informations that I find in one place are different in an other place.

I just hope that someone who really understand these could help me.

Thanks a lot.

 

[edison123]

Google rotary phase converters and single phase to 3 phase VFD's. Good luck.

Muthu

http://www.edison.co.in

 

[waross]

What Edison said. By the way, the third motor is not a three phase motor.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[davidbeach]

I don’t know, maybe I’m just too jet lagged, but a single phase of a single phase of a 380V ought to be close enough.

I’ll see your silver lining and raise you two black clouds. - Protection Operations

 

[panter]

Suchara,
you probably saw the connection of a three-phase motor using a capacitor to a single-phase system. It does not give good results and there is a real danger of burning the motor .

 

[waross]

I agree David. Non of those motors needs 380 Volts. They will all run on 220 or 230 Volts.
From there the issue is single phase to three phase.
The motors may be run on single phase with a capacitor but with a serious reduction in power.
A rotary phase converter is probably the cheapest solution.

If you want to "Roll your own" try a 1/2 HP, 3 phase motor started and run with capacitors. That should develop enough back EMF to run those two small motors on three phase.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[itsmoked]

Much much cheaper than a rotary phase converter is a VFD.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[cuchara]

Thank you very much for your answers they helped me understand many things

yes, the third motor is mono, can you help me choose its capacitor / s?

yes, they all work at 230V but I have others that work at 380

I don't mind losing 30% power on some of themes.

I am very interested in this particular model; Link
It seems too simple to me, I don't know that they existed

I see that the 5kw model takes more than 30A that can burn any extension, right?
How do you connect them?

 

[waross]

For 230 Volt try an 80 uf capacitor as per the nameplate.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[cuchara]

It is written on the plate I thought it did not say anything because there is a lot of space before uf, What does the P stand for?

 

[jraef]

When using a capacitor to make a 3 phase motor spin on single phase you don’t lose 30% of the motor power, you lose 50% or more, especially in terms of PEAK torque, which the motor uses to re-accelerate when a load is put on it. That means it becomes very easy to stall the motor.

Those are old motors and not likely to survive long being run from an inverter drive. The lure of “free” motors is intoxicating, I know, but the reality of trying to make them work is often not worth the price you paid for them…


" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden

 

[cuchara]

ok ok i got you

I had those motors for free

What interests me is that they have reducers so even if they lose their power they can be used for a machine that turns parts at very low speed to weld

Why can't old motors survive a variator?

what has changed the most?

 

[waross]

variator?
Do you mean a Variable Frequency Drive?
The winding insulation does not stand up well to the high voltage stresses imposed by the effects of the high frequency puls width modulation switching.
Even new motors are at risk.
Inverter grade motors have enhanced insulation to withstand the high voltage transients.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[cuchara]

yes I mean VariableFD

ok thanks for the explanation

 

[cuchara]

Thank you very much for your help
I learned many important things that will help me make future decisions I was right to come here.

I already have the 80uf capacitot for the third motor
But my question now is which coil do I have to connect it to?
I only have 6 scrambled wires with no name I managed to separate the 3 coils but now I wonder which of the three I have to connect the capacitor is it a starting or permanent capacitor?

 

[waross]

The two windings with matched resistance will be the running windings. I parallel for 110 Volts, in series for 220 Volts. Polarity matters.
The odd winding will be a 110 Volt starting winding. It connects in parallel with ONE run winding. That is from one line to the center connection between the two run windings so it sees 110 Volts.
The capacitor goes in series with the start winding.

is it a starting or permanent capacitor?

If you have a starting switch or starting relay, the capacitor is a starting capacitor, else a run or permanent capacitor. If the capacitor explodes, you have probably used a starting capacitor when you needed a run capacitor.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[waross]

On an old motor, if the starting switch is broken beyond repair, look for a starting booster in refrigeration supplies. It is a capacitor and electronic starting switch in a package.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[cuchara]

Thank you very much for your answer, you explain it very well but my familiarity with the subject is not enough to understand everything.

How am I supposed to find the polarity of the coils?

starting switch or starting relay

I hope it is a running capacitor because I do not have any supplementary data on this motor all I achieved was to separate the coils as shown in the photo

am going to use it in 220 V so I have to connect it in a star,But first I have to find the polarities right?

 

[edison123]

For the 220 V, you have to connect it in delta. See the motor nameplate.

Muthu

http://www.edison.co.in