A frequent question in this forum and others is, what is the "standard" voltage in one country or another. This FAQ will attempt to collect this information in one place. Since there are many easy to find websites showing residential voltages, this will be primarily for industrial voltages. If there is enough demand (and time) in the future, I may add residential as well.
This is meant to be a collaborative effort of many members, and requires input of anything that you don't see here, or correction if you see a glaring error. Keep in mind however; just because you have not seen something in your country does not mean it does not exist, someone else may have contributed it. I will not challenge any input up front, but if a preponderance of evidence shows me that someone's suggestion was in error, I will edit it accordingly. As the originator, I will be the only one able to edit, but I am not a benevolent dictator, just a facilitator. To send a comment for inclusion or modification, use the link at the end of this FAQ to "Send a comment to the author". I will take care of formatting.
Remember, this is always a work in progress.
3 phase Low Voltage
USA: All 60Hz[ul]Official / Common: (quasi-official, it can vary from one utility to another) [li]480Y277*[/li][li]480 delta*[/li][li]240/120 4wire center tap ("red leg") delta*[/li][li]208Y120*[/li][li]240 delta[/li][/ul]
[ul]Defacto / Legacy: [li]600V delta (isolated areas)[/li][li]480V corner gounded delta[/li][li]440 delta[/li][li]200Y115[/li][li]240 open delta[/li][li]240 corner grounded delta[/li][/ul]
3 phase Medium Voltage
USA: All 60Hz[ul]Official / Common: (quasi-official, it can vary from one utility to another) [li]34500Y/19920*[/li] [li]24940Y/14400*[/li][li]13,800 delta*[/li][li]12,470Y7200*[/li][li]13,200Y7620*[/li][li]4160V delta*[/li][li]4160Y2400[/li] [li]2400V delta[/li][/ul]
[ul]Defacto / Legacy: [li]34500 delta[/li][li]23000 delta[/li][li]22860/13200[/li][li]20780Y/1200[/li][li]8320Y/4800[/li] [li]6900 delta[/li][li]4800 delta[/li][/ul]