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	Subject - Dist. Panels used as disconnect switches Steven T. SITUATION: Power is supplied to two separate buildings by way of a single distribution panel which in turn is controlled by a 'switchgear' ("disconnect switch"). Each building has it's own distribution panel which are bonded to the building's EQC (ground rod) and in this case only one rod for each building and for each of the three distribution panels (including the power source's disconnect enclosure/switchgear. PANELS: Each enclosure has a grounding rod (the number of rods for each box is not of issue) and each enclosure has it's own "EGC" (a copper wire) which connects each panel to that panel's ground rod. SERVICE CABLE: The single phase system's direct burial cable consists of a 3 wire conductor with an armor shield that is fairly well secured to the districution panel and the distribution (disconnect) switch's panel box by way of what appears to be compression fittings whichsecure the exposed cable's enried into the bottom of both box's. MY COMMENT: Regardless that there's an EGC and GR installed on and for each panel, I see the code as requiring a "bonding jumper" (a dedicated conductor and not the panel bodys alone) to properly bond this cable's shielding to each of the panel's EGC terminal. I do not see the panel's sheet metal as being suitable as a dedicated grounding source regardless that it seems to meet the standards for electrical panel construction. MY QUESTION: Does not the code [ 250.130(A)] require this scenario's shield to be bonded to more than just each panel's body and accordingly does not the NEC/IEEE require this shield to be connected directly to the EGC's terminal by way of a suitably sized copper conductor? TO REITERATE: Does not the NEC/IEEE require a dedicated and listed conductor for grounding in this scenario? I see the NEC's 250.130(A) as being written to assure that installers do not reply on a sheet metal box's construction (i.e.; a spot welded carbon and hinge bodied steel panel as being suitable for a permanent and reliable EGC w/o the use of a suitable and dedicated EGC, no? --------------------------------------------------------------------- Many thanks, Steven T. jagerbombme um Ryan_J These remote structures can't be fed with a three wire cable since there is a metallic path between the structures. See 250.32. Also, the conductor that goes from a panel to a ground rod is a grounding electrode conductor (GEC), not an equipment grounding conductor(egc).