Phase Converter

[James Tibbetts]

I am soon going to need a phase converter. The maximum simultaneous load I can envision is a 7.5 hp table saw, a 3 hp jointer, and for arguments sake lets add a 5 hp dust collection system. I have read a good deal about them but time to get the end users input.
Pros, cons, recommendations on sizing, and experiences please with theses animals! Brands to go after..ones to avoid? All information will be welcomed and greatly appreciated!


Jim

[Andrew Hughes]

James I have and run a 10hp Phasemaster From Kay. Its so quite that I sometimes forget to turn it off.
I use it to start a 5 hp direct drive jointer.
I used to have a Rpc from Phonix phase converters and I hated it because it was so load and it rattled the wall next were it was sitting.
So would not recommend them.

[David Kumm]

It's all about the quality of the motor and how well balanced the voltage is under normal load. The more the load varies. the better electonics you need inside the box. Kay and Arco use a special motor ( I don't remember the details ) and don't use start caps, only run caps. You can also just buy the electrics in a box and use your own motor. Different companies size their units differently. Kay and Arco label theirs by the largest hard starting motor it run start, others need to be oversized. When you price out a Phoenix, Great Lakes, or Am Rotary, you must compare a 15-20 hp unit to match a Kay or Arco 10 hp. Read up and talk to different companies. There are forums that talk a lot about RPCs. I ran a Kay for years but now use a Phase Perfect. The PP is expensive but worth it in my world. A 10 hp PP will run your stuff but cost about 4K. The benefit is the voltage is balanced within 2% not matter the motor size. Dave

[James Tibbetts]

Andrew my jointer and table saw are both direct drive . Sounds like maybe a 20 hp unit would easily handle every I have in mind.
David that's good stuff about the comparison pricing. I would not have known that. PP is gonna out of my price range I'm afraid.

[James Tibbetts]

Ouch!! I just looked up the 20 hp Kay unit. $3000

[Andrew Hughes]

When I bought the first converter from Phonix I was trying to stay in a budget and what my service could handle.Since I'm in a residential houses built in the 50s I was limited.
Currently my service from the utility has been pumped up twice with a new line drop and a 27 kW transformer that I share with neighbors.So I could go bigger now.But do your home work
The surge and run from everything must be calculated.You don't want to buy too big of a Rpc and find out you have a soft service.
I still blink the light in the house a tiny bit.
Good luck and call Phasemaster they are great to talk to.

[Steve Jenkins]

When I set mine up I called Kay Industries , told them what I needed to run and bought the one they suggested.no problems in 12 years . I fed mine into a 3 phase panel so I can add more circuits if needed . Mine will start a 25hp and run a total of 75. Not sure about the smaller ones but mine needed a fused disconnect on the incoming side. I started out with a nonfused one because that is what I had and I blew the fuse on the power companies transformer on the pole. Kay is a great. Company to work with and has excellent customer support.

[David Kumm]

James, call Kay but I think a 10 hp is closer to what you need. If that limits you in future you can always run the DC off a vfd and a separate circuit. The 10 hp Kay puts out 30-35 amps on the generated leg if I remember right and multiple motors running help each other out so you can handle more than you think. Dave

[Bradley Gray]

I have a 10 hp Kay also. The spec say it will start up to 10 hp and will run a total of 20 hp at one time.

[James Tibbetts]

I called the power company today to come out and evaluate the cost/possibility of 3 phase to the house. Visit to be scheduled. I had priced the upgrade from my current 100 amp service to 200 amp; and all three of the electricians mentioned that I was probably only getting about 60 amps max on my existing "old style" meter. No idea if that is valid or not, but I'm assuming a 3 ph service will require it's own meter or an upgrade/replacement of the existing.

Dave and Bradley from what I'm reading you guys are on the mark for what I'm gonna need. The 10 hp unit is still not cheap.
Looks like Kay is at the front of the line.

Andrew I will talk with Phasemaster as well. Hard to have too much information.

[James Tibbetts]

Steve that's a big dog of a converter! Way out of my league.
The separate 3 ph panel is exactly what I had in mind. I like the idea of adding new circuits if my layout changes.

[Harold Balzonia]

Phase-A-Matic is a great company to deal with. I live not too far so I just walked in the door to the factory and they were amazingly helpful for a little guy with a little shop. I walked out with a static converter that they just built and tested it right in front of me. They have small static converters and huge rotary ones, as well, in addition to voltage regulators and transformers. Well worth a telephone call... 1-800-962-6976

[Darcy Warner]

Find a good old heavy 254 frame cast iron motor, 1750 rpm, add a control panel. Best control panel I ever owned was from Parrish electric in Monroe IN. All solid state controls. Feed a MLO Siemens panel and pipe your circuit's out of there. 15hp panel from them was 400.00, used motor was 175, surplus panel with breakers was 275, misc wiring, lugs, disconnects, etc. was a few hundred bucks.

[Anthony Spotorno]

Had an American Rotary unit, ultimately pulled it out and installed a Phase Perfect 20HP model.

Every manufacturer of my equipment asked me before they sold me their equipment what type of 3ph unit I had and just about everyone of them recommended Phase Perfect.

Voltages are incredibly stable for all of the electronics in the equipment.

[Darcy Warner]

All the electronics in machines are generally run off a control transformer. As long as you keep track of the generated leg, keep it off any control circuit's, or off the control transformers, there shouldn't be an issue. Ran a few weinigs with accuset heads off phase converters.
Ran a couple other new machines with digital crap off the same thing.

[Bruce Wrenn]

Check over at "Practical Machinest" web site. They have TONs of info, including shop builds for RPC's.

[Bill Dufour]

With only 100 amps total I think you need to upgrade your supply drop. 20hp single phase at 240 is about 86 amps. Add some lights in the shop, maybe heat or ac and you are over100 amps in the shop alone. i believe you only have 100 amps for the house and the shop?
How is you voltage are you in town with stable volts or in the country where it can sag down.
Bill

[James Tibbetts]

Bruce I will put Practical Machinist on my reading list for tomorrow. Thanks.
Bill you are correct on the service.. 100 Amps total. The "shop" is the garage and the driveway. I'm expecting to have to upgrade if 3 phase is available at the house. For now, if I have to, I can limp along with a converter of some type to power the biggest draw, (table saw), and use the single phase dc.
I still need to go through this discussion as I expect to be in a new shop within a year.

[Bill Dufour]

I highly doubt that three phase is even available in your area. If it is you are looking at well over 10,000 to install the service drop. then monthly demand charges. But you should ask anyway.
Also be prepared to ask cost to install 200 or 400 amp single phase service drop.
Bill

[David Kumm]

I run my garage shop with 100 amps ( although a full 100 ) so it is doable with a 10 hp rpc or 10 hp PP. The PP does save a few amps. Not ideal but I can run my 12 hp sander and 7.5 hp dust collector.l I did find that a smaller air compressor was handy to run the WB and pneumatic blast gates so the big 5 hp did not kick in at a bad time.

You can also get luck on CL or ebay as used converters are common. There is a new in the box Arco on the web now. Dave

[Larry Copas]

It pays to ask the right questions.

I built and designed my own 10 HP RPC. The phases are perfectly balanced.....but only for a 5 hp motor. Voltage is low when running bigger loads, and high when running a small motor such as a 1 hp grinder. Still within limits. If I had balanced phases for a 10 HP motor voltage might have been too hot for a small motor.

My converter will easily start a 15 HP motor.....but won't come close to starting that same motor when installed in an air compressor.

How many amps does the converter pull at start up? The neighbors might get upset if lights dim. The power company can disconnect service if it interferes with others.

[Patrick Irish]

How many amps would a 15hp RPC need to power? I can't find the answer to that question. If I have a 90amp panel, what's the largest RPC I should install? I'm guessing something in the 40-50amp range would be good.

I have 5hp 3 phase planer and will likely add a larger 7.5 at some point.

[Keith Hankins]

Reach out to American rotary. If you were going to run a single device then I'd say go VFD, but since you will have multipe, call them, they are great to work with. Mine came with a baldor motor. I bought a 10hp that would run a 7.5. First call them tell them what you have and go from there. American made and they stand behind it. I think I just got a flyer from them, and they are having some sales. I was a novice and they worked with me and got me what I needed and it was not the most expensive option. Good luck

[Scott T Smith]

I've run a 30hp Phasa-a-matic for about 10 years without any problems. Other than an occasional shot of grease, it's been maintenance free.

Phase-a-matics used to be popular with machine shops (don't know if they still own this market or not). They have a quality enough output for the CNC electronics.

Mine is installed with a disconnect switch in front of it. It's output feeds a 240VAC 3 phase panel so all of my equipment is on the appropriately sized circuit breakers.

[jack forsberg]

I use the Rotary for other voltages beyound house hold and VFD for anything up to 15HP I offer VDF up to 15 HP out on single phase for $1000 . these are single phase input drives . I built mine but you can buy some good kits .

here is mine


https://www.youtube.com/watch?v=hYVVy0CrUfo