No neutral with 240 volt

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  #1  
Old 11-14-15, 08:25 PM
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No neutral with 240 volt

I am confused about the difference between 110 volt and 220 volt. 110 has a hot, a neutral and ground. The neutral is bonded to the ground at the main panel. With 220 you have two hots and ground but no neutral.
My questions:
What is the purpose of the neutral? I heard it completes the circuit. If so, why is it grounded at the main panel?
Why does a 240 volt appliance such as a water heater have no neutral?
 
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Old 11-14-15, 08:42 PM
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Your house is supplied with 240 volts from a transformer that has a center tapped secondary. From the center tap to either of the 240 volt legs is 120 volt. That center tap comes to your house along with the 240 volt legs and informally called the neutral.

Houses haven't had 110/220 for several decades.

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Old 11-15-15, 03:21 AM
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In addition, on a 240 volt circuit, each leg of the circuit becomes a neutral 60 times a second.

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Old 11-15-15, 05:08 AM
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Why does a 240 volt appliance such as a water heater have no neutral?
A water heater is a 240 volt appliance, no neutral is needed. A neutral is only needed with the branch circuit conductors when 120 volts is required. You cannot get 120 volts from a water heater circuit. On the other hand, a clothes dryer needs both 120 and 240 volts. The motor and controls are all 120 volt, only the heating elements are 240 volt. In this case, a 4-wire circuit is required (120/240 volt). A dryer circuit has 2 hot conductors, 1 neutral conductor and a ground conductor.
 
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