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Discussion Starter · #1 ·
Being American I know very little about foreign power systems. In the US we have 120/240 single phase for residential, and 208Y120, 240 delta, or 480Y277 three phase in commercial and industrial. All at 60 hertz.

Canada has 347 or 600 V ? What configuration is this? Is this 60 hertz?

I've heard of 780 ? Or 960? As well. Then residential in Europe is 220v 50 hrtz single phase? What is the common industrial 3 phase in Europe? How about the middle east or Asia, what sorts of power system are found there? Anybody know any history or theory reasons why these particular systems were developed.
 

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You didn’t mention other power system configurations. I worked in a mill where all the low voltage 3 phase was 575 volts. We also had 2300 volt 3 phase, 4160 volt 3 phase and 6600 volt 3 phase. All of the turbines generators were 6600 volt, both steam and hydro.
 

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I've heard of 575v, but know nothing about it. What configuration is that? I've never been around medium voltage stuff although I would be interested in learning about it.
 

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I've heard of 575v, but know nothing about it. What configuration is that? I've never been around medium voltage stuff although I would be interested in learning about it.
575 volt 3 phase is just like 480 volt 3 phase. All the motors with the exception of some larger stuff(over 400-500 HP) were 575. Big synchronous motors were 2300 volt, a few air compressors. One motor was 6600 volt, it was a compressor in the oxygen plant.
 

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So is that a Y system? You guys must get away with running some wicked small wires for big loads at 600v. Is it a 208y120 system for the 120 receptacles?
 

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A lot of European countries have 240/415, it's a Y connection, 50HZ.

The nice thing about it is they need only 1 transformer voltage, 240. If single phase is needed, it's just 240. If 3Ø is needed, the transformers can be connected ∆, the result is 240 3Ø 3 wire (no high leg). If higher power is needed, they can be connected Y, the result is 240/415.

Since their single phase stuff is 240 (no 120 over there), no transformer is needed with either system.

Their motors are also 240/415.

Some places have 220/380 50HZ.

400/690 50HZ is fairly common in mines overseas.

I've worked with 2400, both Y and ∆ as well as 2400/4160Y.

Some of the larger buildings around here are 'primary metered' meaning the service voltage is whatever the PUCO lines are, either 7,200/12,470 or 14,400/24,940.

Power plants I've worked on are 13,200 or 13,800.
 

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So is that a Y system? You guys must get away with running some wicked small wires for big loads at 600v. Is it a 208y120 system for the 120 receptacles?
Yes it is a Y. We use it for everything that you would use your 277/480 for, except the voltage is a little higher. I don't know the history behind why.
A rough rule of thumb for 600V is 1Hp=1A. So a 10Hp motor is around 10A, a 50Hp motor is around 50A. I've seen an 150Hp motor with a nameplate of 132A.

Our 3 phase 120V stuff is a 120Y208V system, just like yours, we just step it down from 600V instead of 480V. Some commercial services would be 120Y208V right from the POCO if they don't need big motor loads.
 

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Worked with a fellow here in the states from Sweden. Good worker. Back in the 70's and 80's he said some homes there had 30 amps servicers. But at 220 Y/ 3 phase 4W-there was plenty of power ...
 

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I've heard of 575v, but know nothing about it. What configuration is that? I've never been around medium voltage stuff although I would be interested in learning about it.
A 575 Delta can also be found in old installations like paper and textile mills. The connection hopefully is a corner ground, but a floating system is possible also.
 

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Grew up cutting my teeth on two Phase, Philadelphia had tons of it getting updated. My shop teacher got all kinds of old stuff for us to play with as we had 2 phase in our shop also. Every time I hear an electrician on here say two phase I cringe knowing they don't mean 5 wire.
There was some around here also up until the 1950’s. My papaw sidejobbed a local funeral home-mortuary-crematorium that used 2 phase 3 wire for a freight elevator and I think the combustion air fans for the cremation ovens. The power company had a Scott T I think he said for the conversion.
He hated every day he was there he said, the morticians were ghouls who scared off the small crew that was working, he had to finish it himself.
 

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Work for a water bottling company where all bottling equipment was manufactured in Germany (KRONES) and used 380 volt, 3 phase.
A BIG transformer at each production line dropped the voltage from 480 VAC to 380 VAC.

The big issue we had was the other equipment (conveyors, other auxiliary equipment) that was not manufacturered by KRONES used 480 VAC.

There was one control cabinet had contained both systems, so when troubleshooting you had to be very attentive to what you were checking.

Arrived at work one day in time to stop a possible big mistake.
There had been some problems with one of the machines that ran on 380 VAC.
One of the maintenance "electricians" had convinced the Maintenance Manager and Plant Manager the taps on the transformer were not correct and needed to be changed to get 480 VAC out of the transformer.

The line had been shutdown, the transformer was shutdown and locked out and it was shift change time.
The maintenence "electrician" was told to brief me on the task before leaving.

I about fell out.

Spent the next hour explaining to the managers their "go to guy" was wrong.
I was the "new guy" and not yet "trusted" with my opinion.
Showed them the machine nameplates and the transformer nameplate.
Stopped that potential disaster.

I remember that part of the problem, but don't remember what the original problem was.

The "moral" of the story is you should try and understand the different voltage systems out there, especially if working in production type facilities.


I'm sure it has been covered here a time or two.
For those that don't understand why some countries use 220 volts as their single phase, voltage it's really pretty easy to understand.
If you take a 380 volt phase to phase, three phase,
transformer and measure from one phase to ground/neutral, you get 220 volts.
No need for a transformer.

380 ÷ 1.73 = 219.65 volts phase to ground/neutral
 

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Work for a water bottling company where all bottling equipment was manufactured in Germany (KRONES) and used 380 volt, 3 phase.
A BIG transformer at each production line dropped the voltage from 480 VAC to 380 VAC.
Yep we had transformers on top of the big control cabinets. We tried to get 480 equipment and US (AB) PLC's installed once and only once, they did not get it.
We used vacuum pumps for suction on some lines, asked for 480 volt, ok no problem. The made the line 480 volt motors. Problem was they replaced the motors but did not redesign the mechanical parts, so a 60hz vacuum pump ran at 3450 RPM not 3000 RPM. Load went up motors burnt up.
 
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Adapting foreign production equipment to US frequency and voltage can be both fun and challenging at the same time. Disastrous if adapted the wrong way.

Many times a 380V/50Hz motor can be run directly on a 460V/60Hz system, depending on the load type, it will run 20% faster, but the volts/Hertz remains the same. Some load types the extra speed is not a problem, other load types the extra speed and loading can be disastrous. That keeps it interesting because each case needs to be evaluated separately.

If the extra speed causes excessive loading compared to the nameplate values, then it's time for a 60Hz motor with the proper power rating or a VFD drive to cut the frequency down to the 50Hz the motor/machine was designed for. Belt driven equipment gives one more option to change the sheave ratios to make it compatible.

But many times just changing the voltage and leaving the frequency the same (higher) can also lead to problems. Each case needs to be evaluated on its own, for a permanent reliable fix. This makes each case an interesting study in adjusting compatibility.

Even VFD conversions can have issues, 50Hz motors come from places that use Wye power systems and their typical VFD drives require a Wye power system. If you install it here on a delta power system, your like to have VFD drive problems. Lots of details usually to look into for a successful continent conversion. It keeps it interesting.
 
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