Thread: 575 Volt 3 Phase - Who Uses it?

Hi all,

Due to a vendor error, I have to dispose of a 3 HP 575 volt 3 phase explosion proof motor.

Who uses this type of electrical service (575 V 3 P) ? Are there certain industries where this is common?

Or maybe, its a really nice, brand new boat anchor for a, shall we say, 'substantial' boat.






Thanks for any help.

Jess

550-600 volts was common with textile mills in the South. But the only textile mills still in business are concerned with automation on a large scale and would have no interest in one surplus motor for sale somewhere.

550 volts is prevalent in parts of Canada still I think...perhaps a Canadian can address this.

480 volts is of course standard voltage for mid and large size concerns in the USA and that motor would run just fine on 480 volts, allbeit at a slight reduction in horsepower. My facility is 480 volts and if I needed your motor, I wouldn't hesitate to buy it myself if the price was right. (if it's *real* right I might buy it anyway as I'm thinking of setting up a spray booth ) The problem is convincing other 480 volt folks that running a 575 volt motor would not hurt it in the long run...I know it's fine, but "they" may not and will therefore be hesitant to buy it.

575 is the Canadian equivalent of our 600 volts.

In general, there is "300 volt class" and "600 volt class".

480 is really 277/480 Wye, and because the line-ground voltage is under 300, 277/480 is actually in the "300 volt class", as is 120/240 Wye and 240 Delta.

Note that that is a special "Marine Duty" motor, undoubtedly intended for service on USCG regulated ships.

And, undoubtedly priced accordingly.

I'm sure ... for a price ... a 600 volt class VFD could be found for this unit.

In which case it would be a good candidate for a lathe or other machine tool conversion, one which is operated in an explosive atmosphere.

Yes, a spray booth would be a good application.

Don, did you notice that this motor is a face mount? Recon you just happen to have those particular face dimensions on a driven machine laying around your shop?

Holy smokes, that's a heavy duty motor. I've never seen a cast iron wiring can before.

Keep in mind the can needs to be *sealed* as in airtight. The comparatively chintzy stamped steel and cast aluminum jobs won't compress the gasket enough.

Does it have a mount for a feedback encoder?

Also I was under the impression that Canada's 575vac was equivalent to our 480v. A couple pieces of plant equipment we inherited as "hand-me-downs" from a Canadian plant were 575vac, 3ph input to the control panel and 575vac, 3ph electric motors. Thankfully the control voltage was 120vac so changing that was as simple as chucking the control transformer and obtaining USA motors.

-Matt

You could use it in a 480 Vac system with a 480 Vac VFD, but only up to about 1400 RPM (50 Hz). Above that there wouldn't be enough voltage to maintain the V/Hz ratio, and the motor would draw excessive current.

Another option would be to use a 480 Vac to 575 Vac step-up transformer to feed a 575 Vac VFD. That way you could get the full speed range.

The ideal solution would be to find someone in Canada that wants it.

John

"The ideal solution would be to find someone in Canada that wants it"

How about a U.S. 600 volt system?

How about a U.S. 600 volt system?

I guess that would work too, but D had already said he thought it would be a tough sell:

But the only textile mills still in business are concerned with automation on a large scale and would have no interest in one surplus motor for sale somewhere.

John

Thanks for all the helpful input on this.

I don't believe it has provisions for an encoder.

The weight is around 130 lbs, 141 lbs on a skid ready to ship, which would benefit a local user that would not require shipping, if one can be found.

I guess If I ever decide to sail up the east coast I could dock at Don's and drop it off?

Thanks,
Jess

yea on my grand parents farm on one of the old sylos we have a 550 3 phase on the auger just thought ide say that

600 volts or 575 volts, no differnce really, just a slight increase in cuurent (amps) when your electrical system puts out 575 instead of 600 volts.

The city I live in ,(Calgary Alberta) will only provided 600 volt electricity to new industrial customers. This is for voltage drop reasons. If you want 480 3 phase or 208 3 phase, you have to provide the transformer to do so.

A week ago, in a very large and heavily growing industrial park here, I measured line to line voltage supplied to a large welding -machine shop. At 11.00 am, which is a heavy use period, voltage was 582 v, line to line, or phase to phase. At 12.10 (lunch time) it was 604 v.

I have measured this difference several times. Bigger loads from the customers equals slight voltage drops. As far as electricians are concerned here 575v equipment and 600v equipment are the same thing.

575 vs 600V is just semantics. 575V is the "Utilization voltage" for motors, while 600V is in reference to the "Distribution voltage" supplied by the utility, and is the "standard" in most of Canada. In the US we have 480V as the Distibution voltage and 460V as the utilization voltage, 240V distibution vs 230V utilization etc. etc. This is because the motor mfgrs use a lower rating in order to compensate for some expected voltage drop without sacrificing performance and to provide a compromize for older systems still in use that were 550V or 440V. All new motors are 230/460V or 575V now.

As mentioned by others there are pockets of 600V distibution throughout the US such as many Southeast textile milss, but for the most part it is rare here. You best bet is to return it or look to a surplus outfit to find a home for it.