Greenfield.
The trade name for flexible metallic conduit.
Ground Fault / Ground-Fault Overcurrent.
(1) An abnormal connection in an electrical circuit, where the normal load path is either partially or completely bypassed through this non-circuit return path, which is the equipment-grounding system of an electrical power distribution system. The low impedance causes high-magnitude values of overcurrent to flow at the point of fault in the circuit. (2) A flaw in an electrical circuit in which some or all of the circuit current is escaping and flowing to ground or along the equipment-grounding system back to the power source ― bypassing the connected load. These faults pose an electrocution hazard due to the level of current involved. (3) An unintentional, electrically conducting connection between an ungrounded conductor of an electrical circuit and the normally non-current-carrying conductors, metallic enclosures, metallic raceways, metallic equipment, or earth.
Grounded (Grounding).
The connection or act of connecting a conductive body to the ground or to another conductive body that extends the ground connection.
Grounding Electrode.
A grounding electrode is a conducting object through which a direct connection to earth is established. As used with the grounding of the electrical service in a building or other structure, this electrode is the conductor or other material that physically connects the electrical system to earth ground. Several types of these electrodes are recognized by the NE Code: underground metallic water piping systems, metal rod and pipe electrodes, ground rings, and rebar or bare-copper conductor concrete-encased electrodes.
Grounded Neutral or Grounded-Return (Grounded Circuit) Conductor.
All three terms describe the grounded conductor in an electrical circuit. The NEC does not address the single-phase AC grounded-circuit or grounded-return conductor as a grounded neutral conductor because it carries the full-load current of the single-phase AC supply. By NE Code requirements, two or more phases (single-phase AC sources) must share this common grounded conductor for it to be addressed as the neutral conductor in the multi-wire circuit.
