Missing Grounding Conductor (EGC) in Service Disconnect.

250.24  Grounding Service-Supplied Alternating-Current Systems

(A) System Grounding Connections.

A premises wiring system supplied by a grounded ac service shall have a grounding electrode conductor connected to the grounded service conductor, at each service, in accordance with 250.24(A)(1) through (A)(5).

The grounding electrode conductor used to bond the service grounded (neutral) conductor to the grounding electrode(s), can be installed at any accessible location from the load end of the service-drop or service-lateral up to and including the service disconnecting means.

Electrical systems are to be grounded (earthing) and connected to the earth in a manner that will limit of voltage and called by lightning, line surges or unintentional contact with higher voltage lines and that it will stabilize the voltage to earth during normal operation.