The ground and the neutral are permitted/required to be connected at 1 place only.
That place is where the power first enters the building and is referred to as the Service.
From that point forward, those 2 wires are never supposed to be connected together ever again.

The reason behind that stems from the behavior of circuit breakers and (also) fault currents. The system is designed to be installed with that single point of commonality between the ground and the neutral and everything that you can buy and install has been designed and tested with that constraint.

If the ground and neutral get connected together in more places, problems can develop that are very difficult to find and fix.

Connecting them together willy-nilly as the old boss said to can cause ground loops, strange behavior of electronic equipment and a host of other potential problems.


Ghost307