Rotary Phase Converter (Create 3-phase power from a single phase source)

[Frank S]

Some food for thought. if you already have 1 rotary converter with or without the starting assistance of a pony motor you can parallel in idler motors till kingdom come as long as your line amperage is sufficient to handle the per phase load amperage of the equipment which is going to be run off of the converters.
I often use the motor on my end mill as a booster idler for when I need tr run heavy loads on my lathe and vice versa. I do this because my converter is the same size as the motors on the lathe and the mill which means either must be started under no load. Ideally I would have a 5HP converter.
Here is a chart which shows the maximum amount of installed HP which can be run on a given sized converter as long as all motors are lightly loaded and not started at the same time. the chart also describes how multiple converters may be linked together for starting larger motors
Attachment 21883
If I had some large capacitors I would be tempted to see if I can get my little 3 hp converter to start an 8 hp inverter rated motor that I have and allow it to run as an idler in parallel to see if I would have sufficient power to rower up a 240 to 480 v transformer that is needed to run my 7.5 HP Cleereman index drill now that the electric co has installed new 2 ought feeder lines to my meter as opposed to the old #4 AWG lines I had before. I might have to add a 3 hp idler before the 8 hp but that would or should according to the chart give me the equivalent of a 14 HP converter

According to Phase-A-Matic, Inc.
Due to the high in-rush current required to start a motor (5 to 10 times the normal running
current), most applications require sizing the HP of the Rotary Converter 50% larger, or
more than the horsepower of the largest motor, or any combination of motors started at
exactly the same time. The first motor started, if not running heavily loaded, generates
additional 3-phase power back into the circuit. You can then run additional motors provided
they do not run heavily loaded and are not started at the same time. A maximum of up to 3
times the HP rating of the Rotary Converter can run at the same time - if not heavily loaded,
and not started simultaneously. For example, a 30 HP Rotary Converter potentially could
run motors totaling up to 90 HP.

[Frank S]

If you are going to have to try and run any 3 ph CNC equipment you need to also have a voltage stabilizer which is as near as I can ascertain is something like a static phase converter and a bank of capacitors tied into the rotary converter.

[JeffEck]

Thank you, David and Frank, I am going to do some experimenting and see what happens.

[Supraman]

do these plans only show using a pony motor to start the idler motor ?

[nhengineer]

The plans are complete including the schematic and all the necessary purchased parts information. If you buy the plans and you're not satisfied, Jon has a 100% guarantee. Of all the converter plans sold, no one has asked for a refund yet. If you find something not to be clear or missing, contact me here and I'll get what you need.

[Supraman]

The plans are complete including the schematic and all the necessary purchased parts information. If you buy the plans and you're not satisfied, Jon has a 100% guarantee. Of all the converter plans sold, no one has asked for a refund yet. If you find something not to be clear or missing, contact me here and I'll get what you need.

Thanks, I might be being picky but, I don't want to use a pony motor to start the idle motor. Was hoping your plans included using start caps to get the idle motor started. I've also seen plans that include a time delay and a relay to take the start caps out of the circuit. I'm just a dumb guy farting around in his garage so I can't figure everything out on my own. I need a wiring diagram for dummies :P

[nhengineer]

A guy who bought my plans used a rope around the converter motor pulley instead of a pony motor. He told me it works slick but that was many years ago.