440 motor question

[Bill Dufour]

I am looking at a bandsaw with a 440 motor. are these normally changeable to 208-240 3 phase? this is a powermatic 87.
Bill D

[David Kumm]

If the motor is dual voltage and has more than 3 leads in the motor P-head, you might be good. If there are only 3 leads, the others might still be buried inside the windings but unlikely. Figure 300-500 to replace, rewind, or transform the voltage from 240-480. Dave

[roger wiegand]

Look at the plate on the motor case. It will almost always tell you. (are you sure it's not 480? That would be the more typical voltage)

Unfortunately buck/boost transformers for three phase aren't cheap, you may well be better off swapping motors if it can't be rewired for 208.

[John McClanahan]

If it is dual voltage it should show wiring for hi voltage and lo voltage. The lo voltage being 220-240 volts.

[Carlos Alvarez]

Consider what it would cost total if you sold this motor and bought the correct one instead.

[Jeff Heath]

Motor plates aren't always accurate. When I bought my Monarch lathe, the 15 hp motor was marked "440V only". When I opened up the peckerhead, it had all the wires for dual voltage, and I simply changed it from Hi to Lo. Easy enough to do if your wires are number labeled.

If not, as Dave stated, often enough, a motor shop can pull the wires for you without a rewind. It all depends on how it was wound in the first place.

PM 87 is a fine saw. I used to own one. Nothing too remarkable, as I recall, about their motors, and you could probably find a 220V 3 phase replacement pretty easily for it.

[Bill Dufour]

The Model 87 is being sold for $1,000 but it is wired for 440 according to seller. He is not sure if welder works or not. Glad to hear the motor is likely switchable to lower voltage. Just more information to make price negotiations with. Problem is it is about 400 miles each way from me and it is 3/4 of an inch too long for my Ranger pickup.
Bil lD

[Steve Rozmiarek]

Bill, it's VERY likely that is a dual voltage three phase motor. 3 phase machines in the US are commonly installed on "residential" 3 phase or 208 volt. 480 volt is less common for the environment that a heavy hobby/light industrial machine will be in, so most motors that are wired for 480 on them, have the taps for lower volt 3 phase too. In a previous career, I changed out dozens of 3 phase motors a year, and it was rare to find a non dual voltage motor. They were usually the really old stuff that lightning had left alone for 30 years.

[Bill Orbine]

The motor controls is the other issue besides the 440 motor. The control may or may not be compatible with lesser voltage hook up. Something to think about on your 400 mile ride.......

[Steve Rozmiarek]

The motor controls is the other issue besides the 440 motor. The control may or may not be compatible with lesser voltage hook up. Something to think about on your 400 mile ride.......

A magnetic starter will use a stepped down control circuit voltage (24 or 120 volt are common), usually it just takes a different lead on the control circuit transformer to set the right voltage.

[Jeff Heath]

A magnetic starter will use a stepped down control circuit voltage (24 or 120 volt are common), usually it just takes a different lead on the control circuit transformer to set the right voltage.

Yes, and very easy to work around. You will also, as stated above by Bill, need to find new heaters for the starter. Most likely, the small transformer for the controls can be just rewired by switching the leads to different "taps". Heaters are dependent on the maker of starter included, and are easily acquired for most vintage starters on ebay for short money, in most cases. Since the voltage of the motor will drop from 480V to 240V, the FLA (fully loaded amp) rating of the motor doubles, thus the need for new heaters. It sounds like a lot for someone dealing with this for the first time, but it really is a piece of cake, and we can walk you through it. Depending on the manufacturer, you'll need to be equipped to turn either one screw, or two, depending on the heater. Really, really complicated.....

[Bill Dufour]

Changing heaters etc should be no problem for me since I do not have three phase in my shop. I will use a VFD and retain the existing pushbuttons for LV control. Folks say a vfd will make the transmission last longer since it will have. a slow start and not a hard lunge on starting and stopping.
Bil lD

[Andrew Hughes]

You lose the lunge but gain a nice high pitch whine. Always a trade off

[Bill Dufour]

You lose the lunge but gain a nice high pitch whine. Always a trade off

You should be able to use auto-tune or manually adjust the carrier frequency to reduce or eliminate the whine.
Bill D
Not a good idea to have wine in the shop with power tools

[John Gulick]

Simple conversion, the motor leads need to be re configured and the coil(s) need to be changed in the starter. A good electrician will know how to complete the work.