Electrical grounding

[Brian2147]

Upgrading my electrical in a triplex . From adding neutrals And grounds and such. Do I need a separate ground from the service disconnect to the panel in my apartment or does the FMC runway handle that.

 

[Jadnashua]

Your individual breaker panel is probably considered a sub-panel of the structure...if that is the case, you need a 4-wire cable: L1 L2 Neutral Ground to it. ANd, in that panel, the ground and neutral wires should be on their own buss. In a main panel, the ground and neutral are tied together, but that should be the only place where that's true in the structure.

 

[Sponsor]

 

[Stuff]

FMC wouldn't provide a good ground. AC or MC would be fine. They may look the same but are manufactured to different specifications.

 

[Brian2147]

Your individual breaker panel is probably considered a sub-panel of the structure...if that is the case, you need a 4-wire cable: L1 L2 Neutral Ground to it. ANd, in that panel, the ground and neutral wires should be on their own buss. In a main panel, the ground and neutral are tied together, but that should be the only place where that's true in the structure.

Thanks

 

[Brian2147]

Your individual breaker panel is probably considered a sub-panel of the structure...if that is the case, you need a 4-wire cable: L1 L2 Neutral Ground to it. ANd, in that panel, the ground and neutral wires should be on their own buss. In a main panel, the ground and neutral are tied together, but that should be the only place where that's true in the structure.

I guess the next question would be what size do I make the ground wire. There a table I can refer to. Thanks

 

[Jadnashua]

What size is the panel's main breaker? Keep in mind, the ground lead should never have any current running through it unless there's a fault. It needs a low enough resistance to trip the breaker, but because that happens in no more than a few seconds, it doesn't need to be as large as the current carrying conductors since it won't heat up much in that few seconds. If you run a new cable rather than individual wires in a race or conduit, it will be sized properly for the current carrying leads. I'm sure there are charts out there...don't know off the top of my head.

 

[Stuff]

I guess the next question would be what size do I make the ground wire. There a table I can refer to. Thanks

NEC Table 250.122 Minimum Size Equipment Grounding Conductors for Grounding Raceway and Equipment