190/380 Volt, 50 Hz Huh???

I found a large cannibalized CNC mill at the scrapyard. No name plate etc, painted white and blue, bottom of casting says Made in Mexico.
It had a very nice Parker hydraulic power pack which I took along with some prime cast iron for gibs, parallels etc..

When I got home I looked at the 2hp, 1425 rpm Baldor motor on the power pack and discovered it was 190/380 volt and 50Hz.

I looked at what countries that voltage is used and none are near the pacific northwest.
List of Voltages & Frequencies (Hz) by Country - Electric Power Around the Globe

How did they run that mill?
Why the odd ball power requirements?
Was this mill destined for the North Korean market? lol

Doug W said:

I found a large cannibalized CNC mill at the scrapyard. No name plate etc, painted white and blue, bottom of casting says Made in Mexico.
It had a very nice Parker hydraulic power pack which I took along with some prime cast iron for gibs, parallels etc..

When I got home I looked at the 2hp, 1425 rpm Baldor motor on the power pack and discovered it was 190/380 volt and 50Hz.

I looked at what countries that voltage is used and none are near the pacific northwest.
List of Voltages & Frequencies (Hz) by Country - Electric Power Around the Globe

How did they run that mill?
Why the odd ball power requirements?
Was this mill destined for the North Korean market? lol

Click to expand...

50 Hz moves more slowly, one Sine-wave to the next. Lower top, wider base, yah get about the same "energy under the curve" 190/380 @ 50 Hz as @ 220-240/440-480 @ 60 Hz. Energy is what matters so JF run it. RPM will be higher as well. Of course.

NB: I could be off a tad. I haven't bothered to do the math.

BEEN done for more than a hundred years, already - several times "Right here, on PM", and not uncommonly right on a motor's data plate as well.

FWIW-nothing_useful:

If it was for DPRK, it would have to run on human feces, and very short rations at that. Time to time, the poor sods go so hungry as to grow cobwebs across their arsehole for lack of regular through traffic.

Think I'm joking, view a satellite shot of the night sky from space:

North Korea vs South Korea at night : MapPorn

South Korea is the part as has electric lights. As do China, Japan, Tiawan, even far-Eastern Russia.

DPRK is the dark gap in the middle.

That ain't ocean.

It is lack of electricity and not a lot to light with it if they DID have it.

The flux density at 190:380V/50Hz is very close to that of 230:460/60Hz and the motor will perform fine on US domestic 3-phase supplies, just add 300 rpm to the rated nameplate rpm associated with the increase in line frequency of 10 Hertz.

motion guru said:

The flux density at 190:380V/50Hz is very close to that of 230:460/60Hz and the motor will perform fine on US domestic 3-phase supplies, just add 300 rpm to the rated nameplate rpm associated with the increase in line frequency of 10 Hertz.

Click to expand...

Thank you!

But why did they spec the 190/380?
Was it to make the machine more marketable elsewhere?

Doug W said:

Thank you!

But why did they spec the 190/380?
Was it to make the machine more marketable elsewhere?

Click to expand...

"Elsewhere", of course. ANYWHERE that the grid is 50 Hz not 60 Hz. That happens to be a rather LARGE percentage of the nations of the world.

Some of them even have the actual electricity, not just a 'standard' for it.

The wealthier ones even industry to USE it:

Mains electricity by country - Wikipedia

Japan was built-out in such a manner that they even have BOTH, and that is a bug, not a feature.

The next level up from "wall sockets" yah need to dig deeper for details of the grid.

But anywhere "50 Hz" appears, so, too will service Voltages generally follow what you have on the dataplate of the motor in front of you.

IOW, it is dirt-common, not at all unusual.

Doug W said:

Thank you!

But why did they spec the 190/380?
Was it to make the machine more marketable elsewhere?

Click to expand...

Only the manufacturer could give a definitive answer. My first employer shipped machines all over the world and many were fitted with 380V, 50Hz motors. Later, more were shipped with 690V, 50Hz motors for cost savings on switchgear related to lower current for a given power rating.

Doug W said:

Thank you!

But why did they spec the 190/380?
Was it to make the machine more marketable elsewhere?

Click to expand...

Market area for 380V is "bit more" than just the north korea. 380V three phase is same as 220v single phase:


Lots of Europe or world was previously 220V nominal(380v three phase), nowadays 230v is a sort of compromise between 220 and 240(UK). Tolerances are mostly overlapping so 220V equipment works fine on 240V and vice-versa with few exceptions. (like 220v light bulbs in theoretical situation that 240v grid would be at the upper tolerance limit)

Doug W said:

Thank you!

But why did they spec the 190/380?
Was it to make the machine more marketable elsewhere?

Click to expand...

It's because the motor was originally DESIGNED for use HERE (North America) as a 230/460V motor, meaning the windings are set up so that the lower voltage is 1/2 of the higher voltage, because that is how WE do things in this country.

Motors create their rated torque by virtue of the relationship of voltage and frequency or "V/Hz ratio", what MotionGuru referred to as the "flux density". So when this motor was made, it was made as a 460V 60Hz motor, so the V/Hz ratio was 460/60 or 7.67V/Hz and as long as the motor gets that, +-10%, it provides rated torque. If you have only 50Hz, as most other countries do, this V/Hz ratio design works fine at 380V (7.67 x 50Hz = 383V, close enough). So this same motor can be used as a 380V 50Hz motor and sold to people in countries that use that voltage, which (at one time) was virtually everywhere else EXCEPT North America, i.e a very large potential market for Baldor.

In those other countries though, "dual voltage" motors are designed differently from ours, they use Wye windings for the higher voltage, then Delta winding for the lower voltage, so the relationship is 1.732:1, not 2:1. That means a "normal" dual voltage motor made for 50Hz countries would be 380V as the high voltage, and 220V as the low voltage.

So BECAUSE this motor was BUILT for use here, but SOLD for use elsewhere, they have to let people know that they cannot use it at their lower voltage, because it is BUILT per our 2:1 relationship. So the nameplate is warning them that the "low" voltage is 190V (1/2 of the 380V), which doesn't actually exist anywhere, so they can't actually use it at 220V and expect proper performance.

Well that explains why I didn't see 380/190 volts used anywhere.

Thanks.

Oh and the scrappies moved some iron so I saw the machine label the Parker power pack came off of and it is a Mazak.

Here is the kicker!

I removed the motor today and saw it has 2 spec plates on it, one with the 190/380 and the other with 208-230/460.
They were on opposite sides and the latter obscured by the gage and control valves etc..

Doug W said:

Here is the kicker!

I removed the motor today and saw it has 2 spec plates on it, one with the 190/380 and the other with 208-230/460.
They were on opposite sides and the latter obscured by the gage and control valves etc..

Click to expand...

Not going to say "We told you so!", but if it isn't too hard to take, how about this instead:

"Why are we not surprised?"

thermite said:

Not going to say "We told you so!", but if it isn't too hard to take, how about this instead:

"Why are we not surprised?"

Click to expand...

You posted a lot of verbiage in this thread, when all you had to say is 'look at the other attached spec plate'. LOL

Doug W said:

You posted a lot of verbiage in this thread, when all you had to say is 'look at the other attached spec plate'. LOL

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Noo... didn't NEED a second plate, nor know if it had one, given it is as commonly done all on just the one plate.

You'd have READ some of the "verbiage", mine or anyone elses, yah might have figured only several million of us out here knew what the numbers HAD to be.

Six eggs or half-a-dozen sorta thing.

Now.... about pouring piss out of a boot by reading the instructions, printed on the heel?

That ain't my kind of advice at all.

MY advice is to not piss in yer boots in the FIRST damned place.

Why did you think God in her infinite wisdom invented POCKETS?

And .. "the good news is.." we should be off to a fair decent New Year.

Enjoy!