(A) Many electricians prefer to reduce the service neutral conductor. However, for most installations and especially for a dwelling equipped with an electric range, electric clothes dryer and electric hot water heater, a neutral conductor one size smaller than the ungrounded conductors is usually more than adequate. It is recommended that the correct neutral size first be determined using the procedure outlined.
(B) NEC Section 220-22 will allow us to reduce the service neutral. Example:
Lighting and appliance load 5100 watts.
Range load reduced 70% (8000 by 70% = 5600 watts)
10,700 watts
10,700 watts - 230 volts = 46.5 amperes
(Prior Code, § 152.37)