The question would be for a feeder to subpanel box in a garage from the main general lighting panelbox in a residential service? Does this application require a three or four wire conductor from main with the neutral conductor isolated from grounds at subpanel? The garage will have a ground electrode/ rod to that location(60 amp or maybe 100 amp with a 200 amp main panel box).
Garage service
- Thread starter dog
- Start date
- Status
Re: Garage service
Dog,
You can never go wrong with the four-wire feeder and an isolated neutral. Just bond your equipment grounding conductor to your grounding electrode system.
Before you can use a three-wire feeder and reground the neutral, you must determine if certain conditions are satisfied. If a metallic path exist between the buildings that requires bonding to the electrical system of each building, i.e., metal water pipes, the neutral can't be used for grounding. See 250.32.
Dog,
You can never go wrong with the four-wire feeder and an isolated neutral. Just bond your equipment grounding conductor to your grounding electrode system.
Before you can use a three-wire feeder and reground the neutral, you must determine if certain conditions are satisfied. If a metallic path exist between the buildings that requires bonding to the electrical system of each building, i.e., metal water pipes, the neutral can't be used for grounding. See 250.32.
- Status