While single-phase power supplies are more common these days. three-phase is still chosen as the power supply of choice for many different types of applications. The generators in the power station provide three-phase electricity. It's a way to provide triple the power along three wires, allowing power to be supplied over two wires without having to increase the thickness of the wires. It is commonly used in industry to drive electric motors and other equipment.
By its very nature, three-phase electricity is smoother than single-phase or two-phase electricity. It is this more consistent electrical power that allows the machines to run more efficiently and last longer than related machines operating in other stages. Some applications are able to work with three-phase power in ways that simply don't work with single-phase power.
Note that since three-phase electricity is rarely used for domestic purposes. the table below is only relevant to electricians, electrical engineers, and other technicians.
| Country/Region | Three phase power (industrial voltage) | Frequency (Hz) | Number of wires (excluding ground) |
| Abu Dhabi | 400 V | 50Hz | 3,4 |
| Afghanistan | 380 V | 50Hz | 4 |
| Albania | 400 V | 50Hz | 4 |
| Algeria | 400 V | 50Hz | 4 |
| American Samoa | 208 V | 60Hz | 3,4 |
| Andorra | 400 V | 50Hz | 3,4 |
| Angola | 380 V | 50Hz | 4 |
| Anguilla | 120/208 V | 60Hz | 3,4 |
| 127/220 V | |||
| 240/415 V | |||
| Antigua and Barbuda | 400 V | 60Hz | 3,4 |
| Argentina | 380 V | 50Hz | 3,4 |
| Armenia | 400 V | 50Hz | 4 |
| Aruba | 220V | 60Hz | 3,4 |
| Australia | 400 V | 50Hz | 3,4 |
| Austria | 400 V | 50Hz | 3,4 |
| Azerbaijan | 380 V | 50Hz | 4 |
| Azores Islands | 400 V | 50Hz | 3,4 |
| Bahamas | 208 V | 60Hz | 3,4 |
| Bahrain | 400 V | 50Hz | 3,4 |
| Balearic Islands | 400 V | 50Hz | 3,4 |
| Bangladesh | 380 V | 50Hz | 3,4 |
| Barbados | 200 V | 50Hz | 3,4 |
| Belarus | 380 V | 50Hz | 4 |
| Belgium | 400 V | 50Hz | 3,4 |
| Belize | 190 V | 60Hz | 3,4 |
| 380 V | |||
| Benin | 380 V | 50Hz | 4 |
| Bermuda | 208 V | 60Hz | 3,4 |
| Bhutan | 400 V | 50Hz | 4 |
| Bolivia | 400 V | 50Hz | 4 |
| Bonaire | 220V | 50Hz | 3,4 |
| bosnia and herzegovina | 400 V | 50Hz | 4 |
| Botswana | 400 V | 50Hz | 4 |
| Brazil | 220/380 V | 60Hz | 3,4 |
| British Virgin Islands | 190 V | 60Hz | 3,4 |
| Brunei | 415 V | 50Hz | 4 |
| Bulgaria | 400 V | 50Hz | 4 |
| Burkina Faso | 380 V | 50Hz | 4 |
| Myanmar | 400 V | 50Hz | 4 |
| Burundi | 380 V | 50Hz | 4 |
| Cambodia | 400 V | 50Hz | 4 |
| Cameroon | 380 V | 50Hz | 4 |
| Canada | 120/208 V | 60Hz | 3,4 |
| 240 V | |||
| 480 V | |||
| 347/600 V | |||
| Canary Islands | 400 V | 50Hz | 3,4 |
| Cape Verde | 400 V | 50Hz | 3,4 |
| Cayman Islands | 240V | 60Hz | 3 |
| Central African Republic | 380 V | 50Hz | 4 |
| Chad | 380 V | 50Hz | 4 |
| Guernsey & Jersey | 400 V | 50Hz | 4 |
| Chile | 380 V | 50Hz | 3,4 |
| China | 380 V | 50Hz | 3,4 |
| Colombia | 220 V | 60Hz | 3,4 |
| 440 V | |||
| Comoros | 380 V | 50Hz | 4 |
| Congo (Kinshasa) | 380 V | 50Hz | 3,4 |
| Congo Republic (Brazzaville) | 400 V | 50Hz | 3,4 |
| Cook Islands | 415 V | 50Hz | 3,4 |
| Costa Rica | 240V | 60Hz | 3,4 |
| Cote d'Ivoire | 380 V | 50Hz | 3,4 |
| Croatia | 400 V | 50Hz | 4 |
| Cuba | 190 V | 60Hz | 3 |
| 440 V | |||
| Curacao | 220 V | 50Hz | 3,4 |
| 380 V | |||
| Cyprus | 400 V | 50Hz | 4 |
| Czechia | 400 V | 50Hz | 3,4 |
| Denmark | 400 V | 50Hz | 3,4 |
| Djibouti | 380 V | 50Hz | 4 |
| Dominica | 400 V | 50Hz | 4 |
| Dominican Republic | 120/208 V | 60Hz | 3,4 |
| 277/480 V | |||
| Dubai（City, THE UAE） | 400 V | 50Hz | 3,4 |
| East Timor | 380 V | 50Hz | 4 |
| Ecuador | 208 V | 60Hz | 3,4 |
| Egypt | 380 V | 50Hz | 3,4 |
| Salvador | 200 V | 60Hz | 3 |
| U.K. | 400 V | 50Hz | 4 |
| Eritrea | 400 V | 50Hz | 4 |
| Estonia | 400 V | 50Hz | 4 |
| Ethiopia | 380 V | 50Hz | 4 |
| Faroe Islands | 400 V | 50Hz | 3,4 |
| Falkland Islands | 415 V | 50Hz | 4 |
| Fiji | 415 V | 50Hz | 3,4 |
| Finland | 400 V | 50Hz | 3,4 |
| France | 400 V | 50Hz | 4 |
| French Guiana | 380 V | 50Hz | 3,4 |
| Gabon | 380 V | 50Hz | 4 |
| Gambia | 400 V | 50Hz | 4 |
| Gaza | 400 V | 50Hz | 4 |
| Georgia | 380 V | 50Hz | 4 |
| Germany | 400 V | 50Hz | 4 |
| Ghana | 400 V | 50Hz | 3,4 |
| Gibraltar | 400 V | 50Hz | 4 |
| U.K.（GB） | 400 V | 50Hz | 4 |
| Greece | 400 V | 50Hz | 4 |
| Greenland | 400 V | 50Hz | 3,4 |
| Granada | 400 V | 50Hz | 4 |
| Guadeloupe | 400 V | 50Hz | 3,4 |
| Guam | 190 V | 60Hz | 3,4 |
| Guatemala | 208 V | 60Hz | 3,4 |
| Guinea | 380 V | 50Hz | 3,4 |
| Guinea-Bissau | 380 V | 50Hz | 3,4 |
| Guyana | 190 V | 60Hz | 3,4 |
| Haiti | 190 V | 60Hz | 3,4 |
| Netherlands | 400 V | 50Hz | 3,4 |
| Honduras | 208 V | 60Hz | 3,4 |
| 230 V | |||
| 240 V | |||
| 460 V | |||
| 480 V | |||
| Hongkong | 380 V | 50Hz | 3,4 |
| Hungary | 400 V | 50Hz | 3,4 |
| Iceland | 400 V | 50Hz | 3,4 |
| India | 400 V | 50Hz | 4 |
| Indonesia | 400 V | 50Hz | 4 |
| Iran | 400 V | 50Hz | 3,4 |
| Iraq | 400 V | 50Hz | 4 |
| Ireland | 400 V | 50Hz | 4 |
| Ireland, Northern | 400 V | 50Hz | 4 |
| Isle of Man | 400 V | 50Hz | 4 |
| Israel | 400 V | 50Hz | 4 |
| Italy | 400 V | 50Hz | 4 |
| Jamaica | 190 V | 50Hz | 3,4 |
| Japan | 200 V | 50 Hz / 60 Hz | 3 |
| Jordan | 400 V | 50Hz | 3,4 |
| Kazakhstan | 380 V | 50Hz | 3,4 |
| Kenya | 415 V | 50Hz | 4 |
| Korea, North | 380 V | 50Hz | 3,4 |
| Korea, South | 380 V | 60Hz | 4 |
| Kosovo | 230 V | 50Hz | 3 |
| 400 V | |||
| Kuwait | 415 V | 50Hz | 4 |
| Kyrgyzstan | 380 V | 50Hz | 3,4 |
| Laos | 400 V | 50Hz | 4 |
| Latvia | 400 V | 50Hz | 4 |
| Lebanon | 400 V | 50Hz | 4 |
| Lesotho | 380 V | 50Hz | 4 |
| Liberia | 208 V | 60Hz | 3,4 |
| Libya | 400 V | 50Hz | 4 |
| Liechtenstein | 400 V | 50Hz | 4 |
| Lithuania | 400 V | 50Hz | 4 |
| Luxembourg | 400 V | 50Hz | 4 |
| Macao,China | 380 V | 50Hz | 3 |
| North Macedonia | 400 V | 50Hz | 4 |
| Madagascar | 380 V | 50Hz | 3,4 |
| Madeira | 400 V | 50Hz | 3,4 |
| Malawi | 400 V | 50Hz | 3,4 |
| Malaysia | 415 V | 50Hz | 4 |
| Maldives | 400 V | 50Hz | 4 |
| Mali | 380 V | 50Hz | 3,4 |
| Malta | 400 V | 50Hz | 4 |
| Martinique | 380 V | 50Hz | 3,4 |
| Mauretania | 220V | 50Hz | 3,4 |
| Mauritius | 400 V | 50Hz | 4 |
| Mexico | 220 V | 60Hz | 3,4 |
| 480 V | |||
| Moldova | 400 V | 50Hz | 4 |
| Monaco | 400 V | 50Hz | 4 |
| Mongolia | 400 V | 50Hz | 4 |
| Montenegro | 400 V | 50Hz | 3,4 |
| Montserrat | 400 V | 60Hz | 4 |
| Morocco | 380 V | 50Hz | 4 |
| Mozambico | 380 V | 50Hz | 4 |
| Myanmar | 400 V | 50Hz | 4 |
| Namibia | 380 V | 50Hz | 4 |
| Nauru | 415 V | 50Hz | 4 |
| Nepal | 400 V | 50Hz | 4 |
| New Caledonia | 380 V | 50Hz | 3,4 |
| New Zealand | 400 V | 50Hz | 3,4 |
| Nicaragua | 208 V | 60Hz | 3,4 |
| Niger | 380 V | 50Hz | 4 |
| Nigeria | 415 V | 50Hz | 4 |
| Northern Ireland | 400 V | 50Hz | 4 |
| North Korea | 380 V | 50Hz | 3,4 |
| Norway | 230 V | 50Hz | 3,4 |
| 400 V | |||
| Oman | 415 V | 50Hz | 4 |
| Pakistan | 400 V | 50Hz | 3 |
| Palau | 208 V | 60Hz | 3 |
| Panama | 240V | 60Hz | 3 |
| Papua New Guinea | 415 V | 50Hz | 4 |
| Paraguay | 380 V | 50Hz | 4 |
| Peru | 220V | 60Hz | 3 |
| Philippines | 380 V | 60Hz | 3 |
| Poland | 400 V | 50Hz | 4 |
| Portugal | 400 V | 50Hz | 3,4 |
| Puerto Rico | 480V | 60Hz | 3,4 |
| Qatar | 415 V | 50Hz | 3,4 |
| Romania | 400 V | 50Hz | 4 |
| Russia | 380 V | 50Hz | 4 |
| Rwanda | 400 V | 50Hz | 4 |
| Saint Kitts and Nevis | 400 V | 60Hz | 4 |
| St. Lucia | 400 V | 50Hz | 4 |
| Sint Eustatius | 220V | 60Hz | 3,4 |
| St. Maarten | 220V | 60Hz | 3,4 |
| Saint Vincent and the Grenadines | 400 V | 50Hz | 4 |
| Samoa | 400 V | 50Hz | 3,4 |
| San Marino | 400 V | 50Hz | 4 |
| Sao Tome and Principe | 400 V | 50Hz | 3,4 |
| Saudi Arabia | 400 V | 60Hz | 4 |
| Scotland | 400 V | 50Hz | 4 |
| Senegal | 400 V | 50Hz | 3,4 |
| Serbia | 400 V | 50Hz | 3,4 |
| Seychelles | 240V | 50Hz | 3 |
| Sierra Leone | 400 V | 50Hz | 4 |
| Singapore | 400 V | 50Hz | 4 |
| Slovakia | 400 V | 50Hz | 4 |
| Slovenia | 400 V | 50Hz | 3,4 |
| Somalia | 380 V | 50Hz | 3,4 |
| South Africa | 400 V | 50Hz | 3,4 |
| South Sudan | 400 V | 50Hz | 4 |
| Spain | 400 V | 50Hz | 3,4 |
| Sri Lanka | 400 V | 50Hz | 4 |
| Sudan | 400 V | 50Hz | 4 |
| Suriname | 220 V | 60Hz | 3,4 |
| 400 V | |||
| Swaziland | 400 V | 50Hz | 4 |
| Sweden | 400 V | 50Hz | 3,4 |
| Switzerland | 400 V | 50Hz | 3,4 |
| Syria | 380 V | 50Hz | 3 |
| Tahiti | 380 V | 50 Hz / 60 Hz | 3,4 |
| Taiwan,China | 220V | 60Hz | 4 |
| Tajikistan | 380 V | 50Hz | 3 |
| Tanzania | 415 V | 50Hz | 3,4 |
| Thailand | 400 V | 50Hz | 3,4 |
| Togo | 380 V | 50Hz | 4 |
| Tonga | 415 V | 50Hz | 3,4 |
| Trinidad and Tobago | 115/230 V | 60Hz | 4 |
| 230/400 V | |||
| Tunisia | 400 V | 50Hz | 4 |
| Turkmenistan | 380 V | 50Hz | 3 |
| Turks and Caicos Islands | 240V | 60Hz | 4 |
| Uganda | 415 V | 50Hz | 4 |
| Ukraine | 400 V | 50Hz | 4 |
| USA | 120/208 V | 60Hz | 3,4 |
| 277/480 V | |||
| 120/240 V | |||
| 240 V / 480 V | |||
| U.S. Virgin Islands | 190 V | 60Hz | 3,4 |
| Uruguay | 380 V | 50Hz | 3 |
| Uzbekistan | 380 V | 50Hz | 4 |
| Vanuatu | 400 V | 50Hz | 3,4 |
| Venezuela | 120 V | 60Hz | 3,4 |
| Vietnam | 380 V | 50Hz | 4 |
| Virgin Islands (UK) | 190 V | 60Hz | 3,4 |
| Virgin Islands (USA) | 190 V | 60Hz | 3,4 |
| Wales | 400 V | 50Hz | 4 |
| Yemen | 400 V | 50Hz | 4 |
| Zambia | 400 V | 50Hz | 4 |
| Zimbabwe | 415 V | 50Hz | 3,4 |