Generator ground bar
- Thread starter anbm
- Start date
- Location
- New Jersey
- Occupation
- Journeyman Electrician
What kind of generator are we talking about ?
hillbilly1
Senior Member
- Location
- North Georgia mountains
- Occupation
- Owner/electrical contractor
Usually just a lug, or a hole for a lug.
Seven-Delta-FortyOne
Goin’ Down In Flames........
- Location
- Humboldt
- Occupation
- EC and GC
Home Standby Generators have a ground bar.
LarryFine
Master Electrician Electric Contractor Richmond VA
- Location
- Henrico County, VA
- Occupation
- Electrical Contractor
In the ATS, yes, but most generators I have installed have had a single lug for the feeder EGC screwed to the metal inside the wiring compartment.
Commercial - standby emergency generator - 408Y/277V, 3PH, 500kW and up... treated as a separately derived system.
Grounding electrode conductor (system ground) will connect to this lug as well? How?
LarryFine
Master Electrician Electric Contractor Richmond VA
- Location
- Henrico County, VA
- Occupation
- Electrical Contractor
I didn't know you meant that large, but residential generators usually don't require GECs, but if they do, there is an eternal GEC terminal.
hillbilly1
Senior Member
- Location
- North Georgia mountains
- Occupation
- Owner/electrical contractor
If it is ordered as an sds, usually it will have a buss bar where the generator neutral is connected and either solidly bolted to the frame, or a jumper to the frame. I’ve had to order insulator kits for that bar when the office ordered the wrong generator when used as a non-sds. And yes, the GEC would terminate there too if used as an sds.
- Location
- New Jersey
- Occupation
- Journeyman Electrician
It should have an EGC bus setup within the generator connection point (like below) unless it supplied an integral disconnect(s).
electrofelon
Senior Member
- Location
- Cherry Valley NY, Seattle, WA
Here is a smaller 150KW generator. The one picture has the breaker and the mounting plate removed and you can see there are studs on the generator housing. The other pic has the breaker installed and you can just see the insulated neutral bar on the left of the frame.
Attachments
To add, If the generator is connected via a transfer switch, then the generator has to be connected to a grounding electrode system such as a driven ground rod.
Otherwise, portable generators with receptacles mounted on the generator (with grounding conductor terminals, all non-current-carrying metal parts bonded to the generator frame) need not be connected to a ground electrode. The generator frame replaces the grounding electrode.
This is a great picture. I attached picture of one generator interior ... I saw at site, I have no clue where the ground bus is, only neutral bar stays next to generator main CB (I assume per code equipment ground wire and grounding electrode conductor will connect to the generator ground bus) if the generator is a separate derived system... downstream ATSs will be 4-pole, switched neutral.
Attachments
So if the generator is a SDS, the neutral bar is also the equipment ground bar and the bar won't be isolated from generator frame?
Fred B
Senior Member
- Location
- Upstate, NY
- Occupation
- Electrician
What is the what looks like a CT on the A/B phase?
- Location
- New Jersey
- Occupation
- Journeyman Electrician
Yes, not sure why there is only one on the A phase and not the B and C phases. There is also one on the EGC bus.
I'm surprised no one noticed the black A phase. This was post pandemic and we could not get wire with the correct colors.
I missed the black conductor.Yes, not sure why there is only one on the A phase and not the B and C phases. There is also one on the EGC bus.
I'm surprised no one noticed the black A phase. This was post pandemic and we could not get wire with the correct colors.
As meticulous as all your jobs are, I'm surprised you didn't re identify it.
Your pictures could serve as a "how to" booklet.
- Location
- New Jersey
- Occupation
- Journeyman Electrician
Actually I did not wire this one but I was involved with other aspects of the project. Yes I would have opted for a few rolls of brown tape.
hillbilly1
Senior Member
- Location
- North Georgia mountains
- Occupation
- Owner/electrical contractor
Yes
The picture I sent, the lone neutral bar is isolated from generator frame.