Bonded Neutral…..

[wwhitney]

250.32(B) disallows this... but the Exception No. 2 may permit no EGC

Exception No. 2 works if there's a system bonding jumper at the "first disconnecting means", as well as at the SDS. So that works if the transfer switch is the service equipment, but doesn't comply if the transfer switch is downstream of the service.

Cheers, Wayne

 

[LarryFine]

Exception No. 2 works if there's a system bonding jumper at the "first disconnecting means", as well as at the SDS. So that works if the transfer switch is the service equipment, but doesn't comply if the transfer switch is downstream of the service.

What about a main-breaker service panel wit an interlock kit?

 

[wwhitney]

What about a main-breaker service panel wit an interlock kit?

Yes that would meet the exception for an EGC feeder from the generator. I would also call that a transfer switch at the service equipment.

Cheers, Wayne

 

[shortcircuit2]

Wow...we got somewhere here...

I don't see a hazard in most applications

 

[LarryFine]

So, I came up with a possible suggestion: make the genny feeder resemble the utility feed?

 

[shortcircuit2]

I just had a phone coversation with "tech support" on a generator manufactured in China regarding the neutral to ground bond in their generator and "how" I might break that bond so the generator could feed a home.

WHY did I call tech support? This was a 13000kw duel fuel generator that a customer got for his home and there is nothing in the owners manual about breaking the bond to float the neutral.

I mean, I knew what to do...and I did the continuity test between N&G on the receptacle and it was bonded. There was guidance in the instructions to install a ground rod in the instructions with a warning of electroction hazard if not done.

Well the guy is trying to tell me that the neutral "is floating". I say that I tested N-to-G and it is NOT floating. He goes on to explain that it is floating with regard to the "earth".

I say "I want to connect to a home and need to float the generator neutral and what do you recommend because there is nothing in the manual?" He tells me to drop the equipment grounding conductor in the cord between the generator and the home inlet. Bingo! Exactly what we concluded in this discussion.

I would say this arrangement would require a GES at the SDS and I was thinkin to jus drop a ground rod where the gen-set is used with a GEC ready to quick connect.

Anyone see any hazard or Code violation with this arrangement?

 

[wwhitney]

I would say this arrangement would require a GES at the SDS and I was thinkin to jus drop a ground rod where the gen-set is used with a GEC ready to quick connect.

Anyone see any hazard or Code violation with this arrangement?

That only works if the transfer switch is also the service equipment. And then isn't the GES connected at the service equipment already sufficient?

Cheers, Wayne

 

[shortcircuit2]

That only works if the transfer switch is also the service equipment. And then isn't the GES connected at the service equipment already sufficient?

Cheers, Wayne

Yes transfer at the service equipment. Yes...GES at the Service and at the SDS with no EGC in the interconnection cord.

 

[wwhitney]

Yes transfer at the service equipment. Yes...GES at the Service and at the SDS with no EGC in the interconnection cord.

I haven't reviewed the relevant sections, but with the transfer switch at the service equipment, and the building GES there, does the generator outdoor SDS need a GES connection, rather than just having a GES connection at the first means of disconnect (the transfer switch on the building)?

Cheers, Wayne