Dedicated Circuits/Isolated Grounds

On a regular outlet the ground screw and pin are bonded to the mounting yolk on the outlet. An isolated ground outlet has the ground isolated from the mounting yolk. In buildings constructed with metal studs,metal outlet boxes are usually also used. When a regular outlet is installed with this type of contruction, the ground is bonded (connected) to all the metal studs in that room and probably the whole building. Electrial noise is introduced into the ground pin of the outlet this way. If an isolated ground outlet is installed the ground will not be bonded to the building metal studs and will not pick up electrical noise. If you install an isolated ground outlet in a metal box you would have to run 2 ground wires the box. One to ground the box and one to ground the outlet. They would both connect to the same ground bar in the panel. The outlet ground has to be insulated so it does not touch any other metal on the way to the outlet. If it did touch metal the isolated ground outlet would be useless. There is no advantage of installing an isolated ground outlet if the outlet box is mounted to wood studs and fed with NM (romex) cable.

Jaffeassc, there is nothing wrong with installing isolated ground outlets in your setup. They cost a bit more and are not needed when the box is mounted to wood studs. You can use regular hospital grade outlets without an isolated ground and save a few bucks. Some people might use isolated ground wiring and outlets if type MC (metal clad) cable or metal conduit is used to feed the outlets even if the metal boxes are mounted to wood studs. The long run of metal surrounding the conductors could introduce some noise into you systemt through the single ground wire connected to the raceway and the outlet. It is a NEC code to ground all metal raceways,enclosures,and boxes. The ground screw to the box must be an approved ground screw and always green in color. You could simply wrap the bare ground wire in the romex cable around the ground screw on the box and then connect it to the outlet. Or use a plastic or fiber outlet box that requires no grounding. Always use the screws on the outlet to secure the wires. Tighten with the loop on the wire going clockwise. If you dont the wire will try to back off the screw when you tighten it. Do not use the push in slots in the back of the outlet. The hospital grade outlets usually have a clamp that the wire goes under and is tightened by the screw. Do not wrap the wire around the screw in this case, use the clamp. Leave 6 inches of wire out of the box to connect to the outlet. Thats a little hard to do with #10 but thats a NEC code too.