Powermatic electric motor

[Danny Smith]

I need a little help. I bought a used powermatic 66 with a 3hp 3 phase motor and really need to find a cheap 3hp single phase motor to replace it. Thanks, Danny

[Jeff Sudmeier]

Danny,

I am not sure, but it may be cheaper to buy or build a phase converter for it, are you sure you need to replace the original motor?

[Tim Morton]

I need a little help. I bought a used powermatic 66 with a 3hp 3 phase motor and really need to find a cheap 3hp single phase motor to replace it. Thanks, Danny

You might try electricmotorwarehouse.com I don't think any 3HP motor will be cheap, but the leeson motors are great, I bought one for my Powermatic 8" jointer and also for my delta 14" bandsaw.

[Todd Burch]

You bought a top of the line saw, and you want to put a cheap motor in it?

[John Weber]

What size the frame and specs, I have some 3 hp Delta motors that might work. They are standard frame sizes and not the special Uni motor.

John

[mike malone]

you'll be looking for "C" face motor...check the shaft it is usually 7/8" x 2-1/2" for the units using 3 belts, the 2-belt models can use a shorter shaft.

you may also be able to use the orig magstarter too, just leave off the the center wires
good luck
mike

[Dev Emch]

In terms of running stuff under 5 HP, your going to find that the bulk of a phase converter is the cost of the idler motor itself. Your better off by just buying a phase converter.

A simple phase converter will consist of one three phase idler motor (5 HP would be nice) plus two oil filled run capacitors, a starter relay and one or two electrolytic start capacitors.

You may find a replacement motor for the saw; however, I sincerely doubt you will be better off. Your going to need to rewire your entire starter and your going to have to replace your heaters. Often I have found that it costs much more money to order the saw as single phase from general or powermatic than as three phase. For 2 to 3 HP, its a wash. For 5 HP, it can be as much as 200 to 300 dollars more!

I would check out fleezbay and other "used" sources. You can buy phase converters whole or in parts or as a "starter panel" which is everything except the idler motor.

And should you get another three phase tool, you investment can be used on that one as well.

Good Luck...

[Steve Cox]

I just bought a 3hp phase converter off Ebay for $318 shipped. It was cheaper for me than replacing the motor of my new Ritter edge sander.

[Danny Smith]

Thank you all for responding. I think I'm going with the phase converter. Does anyone know if a static converter would be okay?

[jack duren]

you can buy a replacement baldor motor for less than $200....rebel

[Dev Emch]

Also keep in mind that every single phase motor out there is putz, kludge or jerry rig. These hamster cage units cannot start themselves so dozens of engineers over the years have come up with all sorts of ways to start a single phase motor. Most of these are liabilities in the woodshop and oil and sawdust can work together to shorten the life of these motors. I hate single phase motors for this reason. Electrical motors are inherently three phase so your always better off using three phase if possible. There is a reason industry prefers them!

[Dev Emch]

Danny...
There are three types of phase converters. Static, rotary and VFD. The VFD is a solid state electronic black box and these are the best way to go but they are also the most expensive. They are also hard to repair and have tons of technical features that will make the first timer's head hurt. One advantage is that if you buy a modular VFD, you can replace the starter in your saw with this unit. The VFD can accept either three phase input or single phase input and it contains all of the conversion hardware. Once done, you will never know that your saw is three phase and its pig tail will be single phase. It also contains your overload hardware so you can forget about dealing with new heaters and overload relays.

One word of caution however! Older motors need one extra protective device with newer more modern VFDs. This is called an RWR filter. That means Reflective-Wave-Reduction Filter. Newer motors are designed to be used with VFDs so this is not an issue. Older motors predate modern switching VFDs so you need to add this one filter. Its not a major deal. Just make sure you dont forget it if the saw is older.

Rotary converters have been around since WW-II. This is what I am using right now and there is nothing wrong with them. They work great. I designed and built my first converter which I used for a few years. My current converter is a 15 HP Kay which is more than most hobby shops need.

As to static converters. Well, this is kind of an oxymoron. If you recall from my other posts, single phase motors need help in getting started. Now a three phase motor can run on single phase power but you need to understand two things. First, your going to have issues getting it started. Second, your going to see a major drop in your namplate power rating. As I recall, its roughly 1/3 less power. A static phase converter is a box full of capacitors, etc. that mimick a two phase power system thus providing a rotating magnetic field to allow the motor to start. Once running, the motor operates more or less as a single phase motor. Most static converters have a red light on them which indicates when the motor is being overloaded due to this modified run mode. If you see the red light come on, BACK OFF the motor!

Most woodworking and metalworking tools do not run in a continuous mode. The power load goes up and down and you never see a long period of continuous use. This is why static converters will work and in some cases is all you need. If your not truely testing your saw, you may be able to live with no issues using one of these. But every case is unique and I cannot say with certainty that your saw will work just fine with one of these. Its a case where you have to give it a try. If your ripping 8/4 oak all the time, I would not use a static converter. If your using the saw as a typical hobbyist, its worth a try.

The major difference between a static converter and a rotary converter is that you have the idler motor which operates as a rotating transformer. Many folks who have started out using static converters have gone and added a surplus idler motor and built a rotary converter using nothing more than a static converter and an ilder motor. The static converter is then used to start the idler which in turn generates or converts the three phase power you need.

My own personal feelings is that I would avoid the static converter. In the long run, your better off with a small rotary type converter rated at about 5 HP.

But one more warning! Three phase, industrial woodworking machinery is extremely addictive. Once you punch the three phase barrier, you will fight yourself from bringing home all sorts of stuff! Keep this in mind when buying a converter. You may be better off buying a 10 HP converter if you can envision yourself bringing home a planer or lathe or what not.

[Gary Bordeaux]

I bought a PM 66 on ebay it has a 5hp 3 phase motor. I am using a static phase conveter and it works great. I will buy any 3 phase tool and power with a static converter. You can usually get 3 phase equipment cheaper even after spending the $100 for the converter. It will lower the power output by 1/3 but I bet you would not notice.

[Hal Flynt]

http://www.taunton.com/finewoodworking/pages/w00126.asp
From the pages of Fine Woodworking Magazine

Making Three-Phase Machines Work in a One-Phase Shop


I found this looking for something else.

[Steve Cox]

Good basic article but their prices are off to me. I just bought a new 3hp rotary converter from Andersen Converters on Ebay. $328 shipped to my door. Works like a champ.