- Joined
- Sep 25, 2014
- Messages
- 1,094
Threads about addressing conversion from single phase to 3 phase come up frequently. Often one aspect of inquiry is how to make 3 phase machines work with as little spend as possible - people have come up with some great solutions. I got into this hobby 35 years ago, and started out with a commercially made, 5 hp rotary converter. The RPC worked great for that first lathe, and made it easy to power the next 8 machines that followed. In all, I think I have 13, 3 phase motors from very small up to 5 hp. The RPC worked well, the drawbacks were that it did not start the lathe well on the higher speed motor setting. With the 4J chuck on I'd get one start and the second start befor too long would trip the RPC thermals. Also, the particular unit was quite noisy (though I have seen others that are much quiter).
I've wanted to play with a CNC machine and when an agreeable opportunity for an industrial machine came up, I took the plunge. This VMC has a 15 hp spindle motor and most of the advise I got was that it was a poor idea to run this unit on an RPC. The best solution would be a Phase Perfect. So off to the store for a 20hp PP. The price tag was painful, it cost as much as the VMC!
Phase Perfect is a solid state phase converter, similar to an RPC in that L1 & L2 pass right through, the voltage balance is essentially spot on and it is rated for motor starting right to the capacity of the machine (20 hp) in my case. Needless to say the 5hp motors start very well (sort of like having 8 new speeds on my lathe to choose from). There is an annoying buzz, which I can't hear as soon as a machine is running.
As a whole shop solution it is awesome. I had to pull a new supply for the converter (it is a higher current device), but for the rest I simply swapped the supply to the 3 phase sub-panel and everything was available to run. The VMC started great (I know nothing about CNC stuff - however that will be another post). I encourage more folks to consider PhasePerfect - and this coming from a person who is a fan of RPC phase converters (and a penny pincher too). I've no affiliation, just a satisfied customer.
I've wanted to play with a CNC machine and when an agreeable opportunity for an industrial machine came up, I took the plunge. This VMC has a 15 hp spindle motor and most of the advise I got was that it was a poor idea to run this unit on an RPC. The best solution would be a Phase Perfect. So off to the store for a 20hp PP. The price tag was painful, it cost as much as the VMC!
Phase Perfect is a solid state phase converter, similar to an RPC in that L1 & L2 pass right through, the voltage balance is essentially spot on and it is rated for motor starting right to the capacity of the machine (20 hp) in my case. Needless to say the 5hp motors start very well (sort of like having 8 new speeds on my lathe to choose from). There is an annoying buzz, which I can't hear as soon as a machine is running.
As a whole shop solution it is awesome. I had to pull a new supply for the converter (it is a higher current device), but for the rest I simply swapped the supply to the 3 phase sub-panel and everything was available to run. The VMC started great (I know nothing about CNC stuff - however that will be another post). I encourage more folks to consider PhasePerfect - and this coming from a person who is a fan of RPC phase converters (and a penny pincher too). I've no affiliation, just a satisfied customer.
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