Does this article require that you MUST run a grounding conductor with the branch circuits? I failed an inspection today in a patient area of an dentist office, because I did not run a separate grounding conductor to the panel. I used a grounding pig tail from my hospital grade receptacles to the back of my metal 1900 box. All the branch circuits are installed in EMT. Is this type of installation suppossed to be redundant? I really dont have a big problem with having to pull a ground to the receptacles (i've got plenty of room) but, I would like to know for the future if I have made a mistake.
Yes, you do need to install a separate insulated equipment ground wire. All receptacles and other electrical equipment in patient care areas require redundant grounding (metal raceway with insulated ground wire). Read 517.13(B)
Bob Where it says shall comply with A and B the B section requires the insulated ground.
517.13 Grounding of Receptacles and Fixed Electric Equipment in Patient Care Areas. Wiring in patient care areas shall comply with 517.13(A) and (B). (A) Wiring Methods. All branch circuits serving patient care areas shall be provided with a ground path for fault current by installation in a metal raceway system, or a cable armor or sheath assembly. The metal raceway system, or cable armor, or sheath assembly, shall itself qualify as an equipment grounding return path in accordance with 250.118. Type AC, Type MC, Type MI cables shall have an outer metal armor or sheath that is identified as an acceptable grounding return path. (B) Insulated Equipment Grounding Conductor. In an area used for patient care, the grounding terminals of all receptacles and all non–current-carrying conductive surfaces of fixed electric equipment likely to become energized that are subject to personal contact, operating at over 100 volts, shall be grounded by an insulated copper conductor. The grounding conductor shall be sized in accordance with Table 250.122 and installed in metal raceways or metal-clad cables with the branch-circuit conductors supplying these receptacles or fixed equipment.