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Single phase to 3 phase for novice. Help!

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Plastic
Joined
Sep 12, 2004
Location
NH
After searching the net and forums I'm more confused then ever. Can you recommend a forum post or website? My situation, I'm moving to a shop with no 3 phase power. 220 single phase is available. I've a 3 phase surface grinder (2hp) and a 3 phase CNC bed mill (5 hp).
I have no idea what would be the best solution for me to power the machines. An electrician is recommending a phase shifter from Amazon for each machine. Somebody told me they might damage the CNC computer. I really don't know what the easiest and best solution for me is. I can't find even good beginner information on what a VFD is.
A friend of mine has a rotary face converter and it is unbelievable noisy, so I don't think that's what I want. I'm a total novice with this and hardly know anything about electricity. So if there are some good sites or posts that are educational, or links to products, I'd be most grateful for links and recommendations.
Thank you so much!
 
Without an Amazon link its hard to make a judgement on what your electrician is recommending, no experience, but I hear the chinese ones are garbage. If cost is of no concern, the Phase Perfect is best. Next would be a VFD, you will need one for each machine, look at them on Automation Direct, might be some reading literature there too, VFD = Variable Frequency Drive. A VFD has to be wired direct to motor, bypassing all stock electrical controls. The low cost option is a Rotary Phase Converter, downside is noise, the upside is there are no sensitive electronics or boards to fry. Plans for a diy rpc can be found here, Fitch-Williams design is what I would use, supposedly if built with an 1800rpm motor they are quieter.

Expect other opinions.
 
No particular reason for an RPC (Rotary Phase Converter) to be any noisier than other motors.

They do tend to be made from cheap old motors, so maybe folks don't change the bad bearings, I dunno.

They are pretty much "stone hammer simple", and very durable. Some CNC stuff is apparently fussy, and needs very good power. Then it is time for a (rather expensive) Phase Perfect.
 
Thank you, to all who replied. I'm starting to think my best option is a RPC. My friends' is so loud, makes you want to wear ear plugs. I figure his must be shot. I looked at the website of North America phase converters earlier. I'll talk to them. I'm afraid Phase Perfect is for now financially not in the cards. I appreciate any advice.
 
Thank you, to all who replied. I'm starting to think my best option is a RPC. My friends' is so loud, makes you want to wear ear plugs. I figure his must be shot. I looked at the website of North America phase converters earlier. I'll talk to them. I'm afraid Phase Perfect is for now financially not in the cards. I appreciate any advice.

As Thermite posted, prob something wrong with, er, there exists large opportunity for improvement.... Changing correction capacitors can change noise, steel end bell on the motor can be loud, etc, etc.

There exists on PM (here) a subforum for RPC's. Google search it for Fitch - a very easy to read schematic will pop up and you're on your way. Your startup RPC could be as simple as a used 3 phase motor with a pull rope scavenged from an old lawnmower. Mine, only slightly more sophisticated than that, has been running my CNC stuff for 30 years.

CNC is generally a little trickier, but doable. Details matter, a lot. Good luck!
 
If you can learn how to make a RPC before the move ...

It's just a three phase motor and a relay with three contacts. Maybe a couple of balance capacitors. Your concern is a quiet motor.
My judge for quiet is that if the target machine is louder than the the RPC motor then you are ahead.
 
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I went through the RPC situation years ago for my newly acquired Jet 1440.
A couple of solid-state conversion trials did not work out at all; kept blowing the capacitors. The thing about this type of lathe is that it starts under full spindle load; I’m sure many other brands do the same thing.

They then made a rotary converter using a Century 7 1/2 hip motor and some caps.
That worked great, but was really loud. (maybe your friends situation?)
It was around $300.

It got so bothersome, that I spent the $$ and bought a Phase-A-Matic converter.
IIRC, it was around $900….. but as I said, this was years ago.
It has worked flawlessly for a long time now.

Fortunately, I was able to recoup the money spent on the hybrid converter as a guy living in the rural area needed one.
 
It got so bothersome, that I spent the $$ and bought a Phase-A-Matic converter.
IIRC, it was around $900….. but as I said, this was years ago.
It has worked flawlessly for a long time now.

Phase-A-Matic static, or RPC? I have a PAM rpc, purchased used, its always been pretty noisy. Its currently disconnected for some remodeling, while down I've replaced bearings and put some vibration isolation feet on it, hoping it will be quieter. If that does not help I am planning to build a sound insulated enclosure.
 
Phase-A-Matic static, or RPC? I have a PAM rpc, purchased used, its always been pretty noisy. Its currently disconnected for some remodeling, while down I've replaced bearings and put some vibration isolation feet on it, hoping it will be quieter. If that does not help I am planning to build a sound insulated enclosure.
Rotary Phase Converter.
It's not exactly quiet, but much quieter than the Century hybrid.
Mine sits on rubber cushions under the work bench.
Also, I used a wall-mounted quality power disconnect to make sure the contacts were engaging/disengaging uniformly.
An enclosure would help with the noise, but allow some air passage.
 
Phase-A-Matic static, or RPC? I have a PAM rpc, purchased used, its always been pretty noisy. Its currently disconnected for some remodeling, while down I've replaced bearings and put some vibration isolation feet on it, hoping it will be quieter. If that does not help I am planning to build a sound insulated enclosure.

Try balancing the rotor. I did and it made a difference on a 5hp motor. Just spun it on two v-blocks. Added nuts to round protrusions around the circumference
of the rotor. The rotor ends (if looked at with the rotor in a vertical position) reminds me of Stonehenge. The right size nuts just threaded on the posts.
Baldor got that right.
 
I've been running an American Rotary 20hp for 10 years and just recently bought a 10hp. Check their site. They have RPC that are set up for CNC.
 
Try balancing the rotor. I did and it made a difference on a 5hp motor. Just spun it on two v-blocks. Added nuts to round protrusions around the circumference
of the rotor. The rotor ends (if looked at with the rotor in a vertical position) reminds me of Stonehenge. The right size nuts just threaded on the posts.
Baldor got that right.

The official way is apparently to put the amount of washers needed on the appropriate stud, and peen it over to hold them.

Bought a used RPC years ago, and it sounded like a clapped out dump truck with a load of scrap on a bad road. I tightened up the sheetmetal, but the real deal was the unbalanced rotor.

Did the washers trick and ever since it has has had a soft whine that is no issue at all.
 
Then it is time for a (rather expensive) Phase Perfect.

The Phase Perfect is now available in an "Enterprise" model, this is basically a slimmed down/less expensive chassis, with fewer add-on options. Comparing the Phase Perfect Enterprise to well-known/name-brand/with-a-warranty RPC's it pencils out to 25-50% higher initial purchase price, depending on horsepower rating you need to support, brand you are comparing against, etc. So yes, it's a bit more expensive, but the gap has closed recently.

A point to consider: in many installations the Phase Perfect actually pencils out cheaper within a year or two of ownership when you factor in power usage and what you will owe your utility.
 
I decided to know the RPC and VFD solutions. I have multiple VFD's and I can build RPC's from scratch.
Not bragging but saying that when you become self-sufficient the downtime is minimal and you are not going
to be screwed by products like a Phase-a-matic. I bought one and returned it. The rotor had a big blob of putty
to balance it. A lot of money for that. I made something a lot better.

DSC_1029.JPG
 
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The Phase Perfect is now available in an "Enterprise" model, this is basically a slimmed down/less expensive chassis, with fewer add-on options. Comparing the Phase Perfect Enterprise to well-known/name-brand/with-a-warranty RPC's it pencils out to 25-50% higher initial purchase price, depending on horsepower rating you need to support, brand you are comparing against, etc. So yes, it's a bit more expensive, but the gap has closed recently.

A point to consider: in many installations the Phase Perfect actually pencils out cheaper within a year or two of ownership when you factor in power usage and what you will owe your utility.


Maybe..... the Enterprise PP is $3100 in 10 HP/240V, probably around 2x the RPC alternative, depending (my price info on RPC may be out of date).

7.5 HP 240V is still $2700,
 
Try balancing the rotor. I did and it made a difference on a 5hp motor. Just spun it on two v-blocks. Added nuts to round protrusions around the circumference
of the rotor. The rotor ends (if looked at with the rotor in a vertical position) reminds me of Stonehenge. The right size nuts just threaded on the posts.
Baldor got that right.

Bingo, i balanced my phase-o- junk. night and day difference, the real charm was when that one could no longer be patched, another story, i bought a panel and a toshiba 40 hp idler, that thing is almost silent in fact ive went home forgetting to turn it off because the old one was , the bucket of bolts type.


When I find it I don’t need it
When I need it I can’t find it!
 








 
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