Electrical theory question...
Let's take as an example 50AMP RV service. A voltmeter between the two hots shows 240 volts, between one leg (or the other) and neutral shows 120 volts. My question concerns what happens when each...
Forum Discussion
larry cad wrote:
This is how you are able to have a neutral conductor that is rated for 50 amps. and yet have two hot conductors, EACH rated for 50 amps. If both hots are running 50 amps current EACH, the total current would be 100 amps. but none of it will flow in the neutral conductor because it will flow back and forth between the two hots. The absolute worst case would be if only one hot wire is loaded (with 50 amps) and the other had no load at all. This would cause 50 amps return current to flow in the neutral wire.
This might help:
Each leg that carries 120v is 180* out of phase with the other. The current carried by the neutral is the difference of the two hot legs. To further larry cad's example above, if you are using 20 amps from one leg and 30 amps from the other, only 10 amps will flow back through the neutral.
This is also why 240 appliances like a clothes dryer for example, have no neutral, just two hot legs and a safety ground.
