American Voltage

[Sanditech]

Hi
I am trying to find the common voltage level(LV)of medium to large industrial plants in North America. All I can ascertain at present is a domestic level of 120V 60Hz P-N.
Which based on the standard UK distribution sytem would give 210V P-P ?
But do industrial (petro-chem) use this as there main LV distribution voltage level?

SANDITECH

 

[dpc]

Common US (Nominal) Voltages (<1000V)

Three-phase:

208V/120V (wye - so 208V P-P, 120V P-N)
480V/277V (wye)
240V/120V (delta with one phase center-tapped - not recommended or widely used)

Single-Phase:

240V/120V (single-phase 3-wire - primarily residential and light commercial)

Some 240V equipment is dual-rated for 240V and 208V, but don't count on it.

HTH

 

[jraef]

Slightly expanded version of dpc's response.

Industrial: US - 480/277 Y is dominant, especially new installations. Some 480 delta is still out there, plus a little bit of 600V in the South East textile industries. Canada (also part of N. America last I checked) - the dominant supply is 600V (delta?), with some 480 systems in select industrials. In some areas the 240V options mentioned by dpc may be the only thing available, but for the most part utilities like to give out 480 for industrials because it means smaller transformers (translate; cheaper).

Medium Voltage: 2300V and 4160V for motors etc., 12.47kV for sub-distribution and 13.8kV for exceptionally large motors.

Commercial (& some light industrial areas): US - 208/120 Y is split in dominance with 240V with center tap because is makes lighting circuits easier to implement. Canada uses 600V in commercial systems as well, but I have been corrected in the past on this so I think they also have 208/120 Y as well (I'm sure some Canadians will pipe up on this).

Residential: Almost exlusively 240/120V 1 phase in both countries. If you get on your knees and beg, they MAY grant you a magnanemous gift of 3 phase power (I know, because I got it after begging for 8 years).

"Venditori de oleum-vipera non vigere excordis populi"

 

[Laplacian]

Our petchem facility has a sitewide distribution voltage of 13.8kV. Utilization voltage for large motors is also 13.8kV. Large motor busses are either 4.16kV or 2.4kV. Low voltage is 480V.

Other common industrial voltages are 13.2kV and 6.6kV.

 

[mc5w]

We also have 347Y600 volts 4-wire 3-phase in parts of Canada and upstate New York.

Highway lighting power is either 480 volts 2-wire end grounded or 240/480 volts 3-wire single phase.

Some parts of Cleveland Public Power have 480 volt ungrounded single phase streetlighting power. Cleveland Public Power did not start grounding their stuff until 1991. You do not want to step on a CPP handhole cover or lean against a streetlighting pole in Cleveland, Ohio because CPP's stuff is only Code 2 out of 3 times. In the late 1980s they were still using GREEN hot leads!

 

[jghrist]

Standard US voltages (ANSI C84.1-1989) are:
(bold-preferred)

2-Wire:
120
3-Wire LV:
120/240
240
480
600
3-Wire MV:
2 400
4 160
4 800
6 900
13 800
23 000
34 500
46 000
69 000
3-Wire HV:
115 000
138 000
161 000
230 000
3-Wire EHV:
345 000
500 000
765 000
1 100 000
4-Wire LV:
208Y/120
240/120 (from delta with one winding center tapped)
480Y/277
4-Wire MV:
4 160Y/2 400
8 320Y/4 800
12 000Y/6 930
12 470Y/7 200
13 200Y/7 620
13 800Y/7 970
20 780Y/12 000
22 860Y/13 200
24 940Y/14 400
34 500Y/19 920

 

[Sanditech]

Thanks to all, having now seen the mass of voltage variants, I'm glad I live in the UK/Europe.

SANDITECH

 

[jraef]

Sanditech,
People think of the US as one homogenous "country" just because we all speak the same language (sort of). We are actually a collection of semi-sovereign states, each with it's own history and developement rate. Many are the same, but many are not. And even within states, control over things like electrical distribution was hotly contested among some cities and economic areas in the early days of electricity as each developed their own way of doing things. Add to that the need to transmit over much larger distances than what you worry about in Europe, and you end up with a list like jghrist's.

You mean to tell me that every country in Europe has exactly the same voltage standards? Wow. Given your history of not getting along with each other, I find that hard to beleive!

"Venditori de oleum-vipera non vigere excordis populi"

 

[jghrist]

And that's just the standard voltages. Most of the transmission lines in my neck of the woods are 100 000 volts - not on the list.

 

[davidbeach]

jraef,

It is actually Europe's history of not getting along with each other that gave rise to a much more standardized set of voltages. WWII wiped out so much infrastructure that they, particularly on the continent, had to basically start over again in the late 40's. I'm sure that if we in the US had to start over we might well have many fewer voltages in use than we do now.

 

[akselj]

jraef wrote:
You mean to tell me that every country in Europe has exactly the same voltage standards? Wow. Given your history of not getting along with each other, I find that hard to beleive!


Untill some 10 years ago England had a slightly different voltage standard, 3 phase 240/415 V, the rest of Europe was 220/380V, it was changed to a common standard 230/400 V.
The difference from the old standards are so small that old equipment can still be used.

In Norway you can find 3 phase 230 V delta.
Most house installations are 3 phase.

England do use a standard plugs for domestic installations that is very different to the ones used in the rest of Europe, and there are some differencies in the grounding terminals, but ungrounded plugs can be used without a converter.

MV installations in factories are normally 3 phase 6 or 10kV

 

[jraef]

davidbeach,
That is an interesting perspective, it never occurred to me. Maybe that is what we are doing in Iraq and Afganistan, standardizing their infrastructure! I'm surprised the spin doctors haven't caught on to that one... yet.

"Venditori de oleum-vipera non vigere excordis populi"

 

[pennpoint]

Yep!! just as I thought; its black copters and 60Hz... We rule.
Say! just how do clocks run on 50Hz anyway?

Best Regards
Pennpoint

 

[RalphChristie]

From the list provided by jghrist:

1 100 000 Volts
Is this the highest voltage in use today in the world? (On transmission lines)

Just curious

Regards
Ralph

 

[bigbillnky]

There are still a few 575V systems out there, but they are rare.

Bigbillnky,C.E.F.....(Chief Electrical Flunky)

 

[akselj]

Say! just how do clocks run on 50Hz anyway?

Best Regards
Pennpoint


If you bring your mains controlled clock you will get a short workday, but clocks are built for 50 or 60 Hz.

Greetings Aksel, Denmark

 

[vonbad]

bigbillnky
I am currently working on a project with the motor voltage at 575; 3?. Have no clue as to hold old the plant is, but it's the specification that was given to me.

 

[jghrist]

575 volts is the standard utilization voltage for a 600 volt system.

 

[Warpspeed]

In Australia thank goodness 240/415 50Hz is universal for residential/light industrial, and the plugs are all the same everywhere too !

However historically the railway industry in each of the seven states started off laying tracks everywhere within their own area, but with a different gauge. BIG problem at the borders hehehe.

 

[alehman]

AFAIK, 765kV is the highest AC transmission voltage in use in the U.S. There are a few +-500kV DC lines.