220 volts, not 200 volts
Why do me measure ac voltage in 220/440 etc.,instead of
200 0r 400 volts ?
Electricity enters a house through the service entrance,
consisting of two 120-volt lines and one neutral line
which acts as a return path for electricity, completing
its circuit. Voltage entering the house can vary by five
percent (6 volts) from the norm of 120 volts, depending
how close the house is to the electrical substation or
the power generating plant. Thus, voltage may be listed
as 115 or 125. This deviation is harmless, because
appliances and lighting devices are designed to operate
with up to 10 percent variation in voltage-12 volts for
120-volt service or 24 for 240-volt service.
I hope that this answers your question.
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Update: June 2012