3 phase converter

[james susick]

Who here has used phase converters. I got my hands on a Baldor 5hp 3phase motor I would like to put on my bandsaw if It will work. I dont know much other then I need a phase converter. What do I need and what is the cost for a converter? The motor is the same rpm as the 2hp 230 on my saw now.

Thanks

[Paul Nienaber]

Factorymation . Com has very reasonably priced phase converters. You should also be able to do some research at their site. I'm no expert, but I've read that you may be limited on the hp rating that it's feasible to convert. $ wise that is. You will also lose some of your hp rating when converted. There will be more knowledgeable people along later to help you out.

[Carroll Courtney]

I made this RPC from a wiring diagram off of the website www.practicalmachinist.com and owwm.org And here,there are several pages of information of what others have done facing the same thing you are.Like the other poster said,phase converter or VFD will be big bucks for a 5hp----Carroll

[David Freed]

I bought a 20 hp American Rotary brand rotary converter and if I ever need to buy another one I won't even consider anything else. Their rotary converters are balanced to be able to deliver nearly full hp. They also sell static converters but they clearly state on their website that, by design, all static converters no matter who makes it will only deliver about 2/3 of the motors rated hp. Their rotary converters come complete with a starter box so all you have to do is run the wiring. I don't know what size converter you are considering but you need to be sure you have a large enough electical service to run one. I installed my converter on a 100 amp breaker.

I disagree with the statement that they cost big bucks. A 5 hp AR converter is less than $500. The 20 hp like I bought is under $1300. For me to have 3 ph service run to my shop was going to cost me $15,000.

[David Freed]

Paul,

Out of curiosity I went to Factory Mation to see what converters they offered. I didn't see any listed, so I used their search engine, and the result said they did not have any. Do you have a link to what you were refering to?

Carroll,

I would like to see the motor you used to make your rpc. Do you have a picture of it?

[Paul Nienaber]

You are correct. They have VFD's that are single phase input and three phase output. Can't remember the other site right now. sorry for wasting your time.

[Steve Kohn]

I don't know where you are but the Chicago CL has what you are looking for.

[David Freed]

You are correct. They have VFD's that are single phase input and three phase output. Can't remember the other site right now. sorry for wasting your time.

No problem. Even though I am sold on American Rotary, I just like to see what other companies are offering.

[Rick Lizek]

[QUOTE=David Freed;1208274]Paul,

Out of curiosity I went to Factory Mation to see what converters they offered. I didn't see any listed, so I used their search engine, and the result said they did not have any. Do you have a link to what you were refering to?

Factorymation lists them under AC Drives not phase converters. You will not learn everything about them on their website. You must talk to their techs when they are open to find out how to apply and size them. The bigger ones list them as three phase in and three phase out but they can still be used as converters. I've told them they need to edit their website becasue people get confused and jump to the wrong conclusions about their products. The site is pretty much written for folks who know what they are looking for and doesn't do well for the neophyte. Very good service and good prices. I've bought four of their AC Drives in the last years for various applications. The Drives do more than operate three pahse motors on single phase. Variable speed, soft start, increasing the rpm are just a few things the Drives will do.

A classic example of the confusion is VFD's don't give full power. Nothing could be further from the truth! Too often they are confused with static converters.

[Carroll Courtney]

Here is my setup that is mounted on my PM90 lathe.Has a Pod on the front so I can set the rpm by just turning a knob.---Carroll

[james susick]

Well the deal is the motor is like new and the guy wants $200. Its not sounding worth it now. I can get a lesson 3hp or 4hp single phase new for $400-$500 here in Pittsburgh. Im only doing it cause my bandsaw does not resaw well, so slow. I was wrong my General 18inch only has 1-1/2hp 230wired. It resaws nice but so slow.

Thanks guys for the info.

[Chip Lindley]

James, I do concede 1.5HP is the bare minimum on a large 18" BS. 5HP on your saw is a bit of overkill. But if the price is right, why not? Eh? IMO you could realize all that your BS can do with a 3HP motor. The 5hp 3ph motor would be close to 3HP run on a static phase converter. 2/3 of 5 = 3.3.

If you absolutely, unequivoquably do not plan to add other 3ph machines to your shop, a static phase converter would be your most economical route. But, since we should never say NEVER, you can keep your eye out for a good deal on an honest-rated 5HP RPC. Once you have one 3ph machine running, uncanny how the bargains just keep popping up!

For many years I have run all my 3ph bargains off of an old ARCO Roto Phase Model A 5hp RPC. Bought at auction for only $165. It has served me well. (up to 5hp) ARCO RPCs are rated HP for HP! They include no horsepower hype!

Another issue as yet unmentioned: You will need a 3ph starter (size 1) for your 5HP motor. Either magnetic or manual with the correct overload heaters installed for your motor's FLA rating.

[Carroll Courtney]

David here acouple of pics of my setup.The S/S is on the side of the cabinet and the plug is at the bottom which is a twistlock.I only have three machines that are 3phase,so I just roll it over by the plug or run a 3phase ex-cord. The slave motor is in my storage cabinet and mounted on drawn slides so I can pull the drawn out if I need to use it for long periods of time.To help keep it cool.If I use it for short periods,I just leave it in the cabinet.Some guys will install a 20hp RPC and hook it up to a 3phase panel and run several outlets,but what I have works for me.----Carroll

[Larry Edgerton]

I run my whole shop off of a 50 hp rotary converter, but......

If I was doing it today I would look at some of the electronic options. VFD's are good for one machine, and I have one on a drill press and it works just fine but there is another type out that will run a whole shop, can't remember the company, but there is a fellow here that bought one so you should be able to find the thread.

Used rotary converters can be found cheap, but they are a bit noisey and need to be adjusted by a professional for the load. As such they can not be all things to all motors and I know I am doing harm to some of my machines with my setup. If and when work picks up I will switch to an electronic. I have a rural shop and no shot at ever getting three phase.

[Paul B. Cresti]

I run pretty much my whole shop off a rotary phase convertor from Kay Industries. It is a 15hp model; Kay rates them very conservatively...they sya the largest motor is can handle is a 15hp and combined total of 30 hp. I have the model with the voltage regulator. It has worked great for me and the support I recieved from Kay was equally great.

I bought it as part of a package deal with my machinery purchase so I actually got a good "deal" on the convertor itself. Do yourself a favor if you are considering getting other 3 phase machines consider a Kay