Electric-Light
Senior Member
In 120v application, I doubt there's any difference in magnetic trip characteristic between 15 or 20A breaker. The difference in thermal trip provides appropriate protection of conductors from overload.
For 100' extension cord, a 15A motor FLA motor load needing a high starting torque will benefit from a 10AWG conductor extension cord, but a 16AWG will do for a 60W work light on a 100' cord.
Even with the 16/3 100' if the hot shorts to ground, there's enough current to activate the magnetic trip.
Since the ground conductor isn't used to carry current, it really isn't subject to overload. It just provides a bleeder ground or a path to short out so if the hot shorts to case, it will trip the breaker.
Why can't we have something like 10/2, 16-ground extension cords?
For 100' extension cord, a 15A motor FLA motor load needing a high starting torque will benefit from a 10AWG conductor extension cord, but a 16AWG will do for a 60W work light on a 100' cord.
Even with the 16/3 100' if the hot shorts to ground, there's enough current to activate the magnetic trip.
Since the ground conductor isn't used to carry current, it really isn't subject to overload. It just provides a bleeder ground or a path to short out so if the hot shorts to case, it will trip the breaker.
Why can't we have something like 10/2, 16-ground extension cords?