electrofelon
Senior Member
- Location
- Cherry Valley NY, Seattle, WA
We are hooking up a service with a 200A DPDT transfer switch for connection to a portable backup generator. My understanding is that since the neutral is not switched, this is not a SDS, and thus a four wire feeder is to be run to the generator and the N-G bond at the generator (if present) is to be removed. Questions (assuming the previous is correct):
1. What is the purpose of seperating the N-G bond on the genny? Consider a fault to the generator frame; with the N-G bond removed, the path back to the source is via the genny feeder EGC, then potentially a 'sub panel' feeder EGC to the service equipment, then all the way back on the neutrals to the genny. What is the health and safety concern that makes removing the bond a safer install despite the drastically longer fault path?
2. Another problem with removing the N-G bond: Without the cord connected to the generator, or when the HO uses the generator somewhere else, there is no fault path if the frame becomes energized. Right? Whats going on here?
3. What does "neutral floating" mean.
1. What is the purpose of seperating the N-G bond on the genny? Consider a fault to the generator frame; with the N-G bond removed, the path back to the source is via the genny feeder EGC, then potentially a 'sub panel' feeder EGC to the service equipment, then all the way back on the neutrals to the genny. What is the health and safety concern that makes removing the bond a safer install despite the drastically longer fault path?
2. Another problem with removing the N-G bond: Without the cord connected to the generator, or when the HO uses the generator somewhere else, there is no fault path if the frame becomes energized. Right? Whats going on here?
3. What does "neutral floating" mean.