Diff btween purpose built RPC motor and regular 3 phase motor

Sorry for the long title, I try to provide enough info so people don't waste their time opening posts to see what's in it.

Anyways,
I would like to know if their is really a big difference between a P-A-M RPC and a good homebuilt RPC using a standard motor.
Below are the specifics on why Phase-a-matic thinks their RPCs are so good.
Are they full of it, or just trying to justify the cost?

I have a Phase-A-Matic rotary converter, according to Phase-A-Matic), it's built on a baldor motor designed as a rotary phase converter, there are no start capacitors, relays or contactors with connections which can come loose or arc.

Therefore they claim their failure rate is zero.

P-A-M's MTBF = "Failure rate (MTBF) is so low it's almost impossible to determine. We find that within the first 12 months approximately 1 in 150 might have a problem, and usually within a few weeks or months. After the first 12 months, it might be one or less in 5,000 over a 30 year period."

Thank you for the info,
Steve

"I would like to know if their is really a big difference between a P-A-M RPC and a good homebuilt RPC using a standard motor."

P-A-M, Ronk, et. al., all have proprietary motors with which they build their IPCs.

Usually, the special characteristics include some form of a low resistance rotor, in order to limit the starting current of the IPC.

Certainly, a standard resistance rotor may be used, and that is precisely what we usually do when we select an off-the-shelf three-phase motor for our IPC's idler.

Many of the proprietary manufacturers claim to be self-tuning, but that is most likely a fiction.

There have been thousands of IPCs constructed by HSMers, using conventional low resistance induction motors, and after "tuning", most of these have been completely successful.

Probably the only thing better than a well-tuned IPC is a Phase Perfect.

Peter,
Thank you I was hoping you'd catch this post.
I see that P-A-M is offering a CNC module that goes woth their regualr RPC, total package runs about 1900 I think.
Would you be inclinmed to think that this compares well with the PhasePerfect?
I think that one runs about 2k as well, IIRC.
Steve

"I see that P-A-M is offering a CNC module that goes woth their regualr RPC, total package runs about 1900 I think.

"Would you be inclinmed to think that this compares well with the PhasePerfect?"

I don't think anything can.

The P-A-M, Ronk, et. al., are "dumb" devices, containing no "intelligence".

The Phase Perfect contains several computers, with which the operation of the converter and inverter sections are constantly being optimized, at least once per cycle (16.67 milliseconds).

I believe the "CNC Module" is a standard low-resistance IPC, with additional run caps added internally, and with which the user can "tune" the device, without actually adding components not supplied within the IPC.

In a sense, the "CNC IPC" is what is says it is: an IPC with which it is possible to get +/- 5 percent without additional components.

That doesn't mean that considerable tuning isn't required to achieve +/- 5 percent.