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Why do they use different voltages for power in different parts of the world? View All

10 years ago - 4 months left to answer. - 1 response - Report Abuse
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Historical reasons. Edison insisted on 110 V (DC) but was convinced by Westinghouse to switch to AC so that transformers (step up/down) could be used. So that became the North American standard. In Europe AEG started with 110 V (following Edison) but at 50 Hz (instead of North American 60 Hz) because it fit neater into the metric system. After WWII the voltage was doubled to 220 V because higher voltages use less copper - which was at a premium. Other countries in the world ususally followed the standards of their colonizing powers. The proliferation of 110 V receptacles and devices in North America prevented the doubling of voltage but that is one of the reasons your large appliances use 220-240V plugs.

10 years ago


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