Can I run this Italian motor on 'Merican electricity?

[Mark Gibney]

This is the motor nameplate on an older Italian band saw I just got

475548

It's 4 hp, 3 phase, 380 volts, 50 hz, 1420 rpm.

I have 240 volt 3 phase at my shop.

Can I somehow use this motor on the saw, keeping to similar rpm, or should I just buy a 5 hp motor and reduce the pulley diameter to keep the same blade speed?

I can get a used 5 hp motor for about $300.
If I put a 5" pulley on the motor, at 1725 rpm the blade speed will be just over 6,000 ft / minute.
The current pulley is 6" and the blade speed is just under 6,000 ft / minute.

I do not know what the alternative voltage that was indicated on the lower right corner of the nameplate is.

Thanks in advance, Mark

[Tom Trees]

VFD/inverters are one way
https://www.youtube.com/watch?v=ddD_7kvxsZo

Congrats on the new machine! :cool:

Tom

[Bill Dufour]

Maybe. Is it star or delta wired?
Bill D.

http://www.gohz.com/star-delta-motor-connection-380v-220v

[Bill Dufour]

VFD/inverters are one way
https://www.youtube.com/watch?v=ddD_7kvxsZo

Most VFDs do not change voltage, just frequency so you would need a transformer. A motor is probably cheaper then a transformer.
Bill D.

[Patrick Kane]

Yep, definitely easier to replace the motor. I have seen guys run high voltage 3 phase motors off transformers, but only on saws that were direct drive. In that case, swapping in a different motor isnt that simple.

How does the motor mount to the bandsaw?

[Charles Lent]

They are all right. Replace the motor is the best and cheapest way, unless the motor is a special design, maybe with a gear reduction or something that is integral to the motor frame.

You can run a 50 cycle AC motor on 60 cycle power, but it will run proportionately faster, since induction motors are frequency dependent.
But then you need the 3 phase power and voltage to be correct within about 15% too, and this will require a transformer. A VFD will allow you to get the speed accuracy if it is necessary for the purpose. So now you need a 3 phase transformer and a VFD. Both are expensive, so my suggestion to buy a new motor for your voltage and speed requirement, if you can find one.

I once worked for a Czech Republic manufacturer who was selling their machines in the USA. About 1/2 of my job involved in matching their machines to our USA power as close as possible. The other 1/2 was doing field service for their equipment in all 50 States and the Caribbean Islands. I got to fix what no one else could, or help them fix it.

Charley

[Greg Quenneville]

The motor nameplate shows the alternative position of the connecting strips for lower voltage. My Italian bandsaw was the same, so I connected it per the lower voltage scheme and used a 240v VFD connected to my 240v mains power.

If you do this take care not to drop the little nuts (7mm?) into the motor. Remind me to tell you sometime how I know that.

On edit:
I just re-read your post and see that you have 240v 3Ø power already, so just change the terminals around and you should be good to go.

Greg

[Rod Sheridan]

The motor nameplate shows the alternative position of the connecting strips for lower voltage. My Italian bandsaw was the same, so I connected it per the lower voltage scheme and used a 240v VFD connected to my 240v mains power.

If you do this take care not to drop the little nuts (7mm?) into the motor. Remind me to tell you sometime how I know that.

On edit:
I just re-read your post and see that you have 240v 3Ø power already, so just change the terminals around and you should be good to go.

Greg

I must be missing something, doesn’t the 380 volt diagram show the motor in Delta configuration?

If so that is the low voltage configuration and The WYE configuration would be 660 volts…..Regards, Rod

[Bill Dufour]

Worst you can do is fry the motor with wiring it wrong. may have to replace it anyway. I would connect for the other way and see what happens. If it for the lower voltage you are good. If it reconnects for higher voltage nothing bad happens.
Bill D

[Tom Trees]

Apologies for being presumptuous about suggesting it would be as easy as I thought, I had a look at the ABB motor on my Euro machine
as I was sure I'd read of 60hz figures on the motor before.

My machine is seemingly only suitable to run at 60hz when 440/480 Y, and no figure given for 60hz Delta,
only other figures on the name plate are for the 220/240 D, and 380/420 Y @ 50hz.

Sorry about that
Tom

[Greg Quenneville]

Well, if that’s the case you can run it using a 240v VFD to get the lower Hz, input either 240v single or three phase, whatever you can buy cheaper. The benefit would be cheaper than a new motor + pulley plus you get soft start capability which is nice on a bandsaw.

[Bill Dufour]

Difference between 50 and 60 hz is not much rpm change. 20% higher at 60HZ.
Bill D.

[Mark Gibney]

When I get advice like on this thread I realize how little I know about motors!
Thanks everyone, and in fact I emailed the Italian makers to get their take on it.
I'll let you know what they say.

Mark

[Dan Friedrichs]

I must be missing something, doesn’t the 380 volt diagram show the motor in Delta configuration?

If so that is the low voltage configuration and The WYE configuration would be 660 volts…..Regards, Rod

Rod is correct. 380V is the delta (low voltage) connection. The other connection option would be wye (high voltage). See this diagram for an example: https://i.pinimg.com/originals/85/53/79/85537942ec9337862ab758e07441e73f.jpg

So the voltage is wrong (either way you configure it) and the frequency is wrong.

You could change the voltage with a transformer, but that likely costs more than a new motor.

You could change the frequency with a VFD, but that also likely costs more than a new motor. You could probably get away with running it on 60Hz, though. It would run 20% faster (60/50), but you could either live with that or change a pulley to get the desired blade speed. It also might slightly stress the motor, so wouldn't be ideal if you are regularly using it near "full power" for long intervals.

But the voltage is the real deal-killer, here. Cheaper to buy a new motor.

[Mark Gibney]

A new motor it shall be.

The Italian company who made this motor emailed me back and told me just what you said Dan.

Thank you all for the education.

[Greg Quenneville]

Hey Mark, I apologise for the dud advice. I didn’t look carefully at the plate, and as Rod posted, its a 380v and higher motor.

Greg

[Mark Gibney]

No worries Greg. The Creek is the hive mind in action and all that.

[Tom Bender]

Hi Mark
So now you get to find out about motor frame sizes. It is usually listed on the nameplate but I don't see it. Google 'motor frame sizes' and find a chart. It may be that you can fit more than one size into your saw. You will need to select one to shop for a motor. You will also need to select hp and rpm.

Next you need to choose blade speed. Typically a band saw has a stepped pulley to allow a choice of speeds. If yours has only a single pulley it may be set up to run production which means a high blade speed. Unless you plan to run at production speed you might want to slow it down a bit.

Selecting a pulley or two is another whole engineering effort. That done you can get whatever you need from Motion Industries.