Types in Present Use
See also: Mains electricity by countryThere are two basic standards for voltage and frequency in the world. One is the North American standard of 120 volts at a frequency of 60 Hz, and the other is the European standard of 220–240 volts at 50 Hz. The differences arose for historical reasons as discussed in the article mains electricity. Usually NEMA type receptacles and plugs are used on 60 Hz systems, and CEE and other types are used on 50 Hz systems, but exceptions exist. The outline maps show the different plug types, voltages and frequencies used around the world, colour-coded for easy reference.
Socket types are sometimes designated by an arbitrary letter designation from a 1998 US government publication, which has no official standing but is sometimes useful as a de facto naming standard when comparing different AC power plugs and sockets.
In Europe, the European Committee for Electrotechnical Standardization (CENELEC) publishes a list of approved plug and socket standards used in the member countries.
Read more about this topic: AC Power Plugs And Sockets
Famous quotes containing the words types and/or present:
“Science is intimately integrated with the whole social structure and cultural tradition. They mutually support one other—only in certain types of society can science flourish, and conversely without a continuous and healthy development and application of science such a society cannot function properly.”
—Talcott Parsons (1902–1979)
“The present era grabs everything that was ever written in order to transform it into films, TV programmes, or cartoons. What is essential in a novel is precisely what can only be expressed in a novel, and so every adaptation contains nothing but the non-essential. If a person is still crazy enough to write novels nowadays and wants to protect them, he has to write them in such a way that they cannot be adapted, in other words, in such a way that they cannot be retold.”
—Milan Kundera (b. 1929)