rotary phase converter motor selection

[ampedtech]

What kind of 3 phase motor should be used for this kind of converter 3450 rpm or 1725 rpm.

Explanation as to why one motor would be better than the other would be cool too.

Any other consideration for motor selection would be great.

 

[tcmtech]

See this thread. https://www.electro-tech-online.com/threads/3-phase-converter-schematic-miller-system.100563/

Typically the higher RPM motors make better converters due to their higher speed and power when compared to a lower speed one in the same size frame .

 

[Jaguarjoe]

When I looked into this a long time ago, I read that an older motor with lots more iron was better to use than the newer chintzier motors.

 

[gary350]

Single phase motors are 3450 rpm or 1725 rpm. I have never seen a 3 phase motor that is 3450 RPM. Most 3 phase motors are 1200 RPM.

If your building a rotary phase convert you need a 3 phase motor RPM is not important. If your building a static 3 phase converter you do not need a motor.

 

[tcmtech]

They come in the two and four pole configurations just like single phase ones as well. The vast majority I have are 1740 and 3450 RPM with only a few 1175 RPM and one 875 RPM three phase.

Depending on what the OP is planning to power a rotary converter unit may be necessary like for a three phase machine or welder or other big device its necessary but for a three phase motor driving a mechanical load its not if the converter box is built right.

Unless he comes back and specifies what he is doing we may never know.

 

[gary350]

There are 3 windings inside of the motor. A static converter uses only 2 of those windings so the motor runs at 2/3 power. A rotory type converter used a 3 winding so the converter runs at full power.

 

[tcmtech]

A static converter uses only 2 of those windings so the motor runs at 2/3 power. A rotory type converter used a 3 winding so the converter runs at full power.

Thats the old and cheap design that was at best 2/3 capacity. My design is balanced system so it allows for full power use on single phase.

It might be worth your time to read my thread!