Generator floating neutral again------- sorry!

I have read many of the posts and pretty much understand what B&D and John and others have said on this subject. I have had a back feed interlock kit (2 pole switched) installed in my service panel along with the entrance box outside the house for the 4 wire cord to plug in to. My question is how do I sever the neutral connection on my generator? I must have to follow the wiring harness into the generator head to do this? Just disconnect it and tape it up?

Question #2 is what are the possible consequences if the neutral is left bonded to the gen frame? I am sure many people aren't even aware that this needs to be done, so I am curious as to what happens if it is not done.
Thanks for the help.

Looks like you have been listening and understanding, thats most encouraging.

To brush up: If the genny, just as the utility, is configured as a "seperately derived source" a "grounding electrode" is required and in cases of portable gensets where plug and cord connected loads are fed from on board mounted outlets, the gennys iron frame suffices as the "grounding electrode" to which the Neutral is bonded and no other "grounding electrodes" are required.

On some small gensets the Neutral to ground bond is right inside the outlet box sorry but I just cant tell you just where it may be formed in all sorts and sizes and brands of gennys out there. Its the Neutral output lead of the genset that somewhere bonds to the case/frame AND ITS THAT BOND THAT MUST BE SEVERED when youre only switching the 2 hot poles and NOT the Neutral.

NOW if you wish to ONLY switch the 2 hots and NOT the Neutral thats for situations where the genset is NOT A "SEPERATELY DERIVED SOURCE" meaning the Neutral is not bonded to any other "grounding electrodes" (such as say the gennys frame) so its unattached and floated out of the genset where it bonds with the utility Neutral. You switch the 2 hots but NOT THE NEUTRAL i.e. you use a 2 pole NOT a 3 pole x fer switch like you would do if the genny were a "seperately derived source"

You ask what happens if not????? Without having to explain all the detail let me say these things: The Equipment Ground is a GroundING conductor intended ONLY as a low resistance fault current return path while the Neutral is a GrounDED Conductor for carrying normal return current. The Neutral is insulated while the Ground is often not. If you dont unbond the Neutral above youre mixin n matchin Neutrals and Grounds (at places othere then the main service entrance)and that could (if certain conditions) pose a shock hazard. The metal cases of say tools is bonded to the equipment ground and you touch them butttttttttt if the ground becomes in paralell with the Neutral (due to improper bonds)and you touch the case then your body is in contact with a hot live current carrying conductor

SURE NOTHING MAY EVER HAPPEN but its NOT worth risking a life now is it???????

PS this is complicated and I cant explain in a sentence what can take books and years of study (to totally answer your question) so dont take my word for it consult the NEC or trained professionals and NOTTTTTTTT the unprofessional untrained inexperienced Billy Bobs of the world who wired their own homes and are now experts lol

CONSULT LOCAL AUTHORITY AND THE NEC AND BELIEVE THEM OVER ME OR OPINIONS HERE INCLUDING MINE IS MY BEST FREE ADVICE

Best wishes n God Bless

John T NEC rusty so no warranty CONSULT EXPERTS nottttttttttttt meeeeeeeeee

PS the reason portable gensets are wired and shipped from the factory with the Neutral bonded to the case/frame is that they are intended for use as a "seperately derived source" i.e. youre not on the grid and the gensets case/frame serves as the "grounding electrode" to which the Neutral is bonded and you attach cord and plug connected equipment onto its own on board receptacles and go to work. Thats similar to at home (seperately derived utility source) in the main panel where the Neutral Buss is bonded to the Equipment ground buss BUT AT THAT SINGLE POINT i.e. SINGLE POINT BONDING

If you want to use the genset and leave its Neutral bonded to case/frame then you would need to use a 3 pole x fer switch and switch the Neutrals for service from either seperate derived sourcers the utility orrrrrrrrr the genny

If you dont sever the Neutral bond and only use a 2 pole x fer switch thats tantamount to re bonding Neutral and ground somewhere downstream of the main home panel i.e. you re bond and effectivley have N and G in paralell paths in which case the iron case of a tool that is bonded to ground (which you touch) then becomes a live current carrying conductive path same as Neutral and you dont go up and cut the insulation away and touch live neutrals now do ya????????? You dotn wnat the body to be another possible current path.

CONSULT LOCAL AUTHORITY AND TRAINED PROFESSIONALS and beware of mis informed though well meaning lay persosns, dont take my word on this consult experts and ther NEC

If I missed anything hopefully other electricians or engineers and trained people can correct me or add to this, Im rusty as an old nail on the NEC, sorry

John T

OK John T, I only use my backup generator to power my well pump in case of an outage. My pump is wired to a box that is 110 only. When I pull the switch off, it disconnects all 3 wires, black hot, white ground, and bare safety ground. Then I plug the genny into the wire going to the pump after the main switch box. Since I have no wires connected to the grid, I assume I am safe. Am I correct on that?
I appreciate your contributions to this forum and always look forward to your posts.
Thanks, Richard in NW SC

Thank you John. It becomes more clear the more I read about this. I now understand the parallel path you described. I will have to look into my genny's head to trace the neutral wire to find where it is bonded. There are 4 wires in the harness coming out of the head. There is no bonding in the outlet box, so it is somewhere out of sight in the head. Thank you again.

Thanks for the kind words. Okay it sounds like what youre doing is safe assuming as it sounds the utility hot and utility neutral and equipment ground are alllllllllll totally removed from and isolated AWAY FROM ANY GENNY CONNECTIONS SO YOU CANT BACKFEED THE UTILITY. Then the gennys 3 wires, Hot and Neutral and Ground are the ONLY wires now getting to the pump right?? and in that case the genny ISSSSS a seperately derived system and its Neutral is bonded to the gennys case/frame and youre permitted to power plug and cord connercted loads off genny mounted outlets which it sounds effectively what youre doing AND NO OTHER GROUNDING ELECTRODES ARE REQUIRED i.e. dont need ground rods.....

Best wishes

John T

Youre welcome, yep assuming the genny provides 120/240 volt single phase three wire service the mid point of its output winding (other outputs are L1 and L2 240 volt) is tapped and a wire from there is the Neutral and somewhere?????????? that is bonded to a copper wire thats bonded to the iron case/frame. The 4 wires, L1,,,,L2,,,,,Neutral,,,,,,Case/Frame/Ground can be resistance checked pretty easy but I just cant say where the Neutral and case/frame bond is ???

Hey it wont blow up and you wont die if its not disconnected but its just NOT the correct way to do things in my opinion which is the same as the NEC method

John T

Thanks John. I have no wires connected to the grid when my switch is off. I appreciate your reply.
Richard

http://www.central.coop/products-services/generlink-transfer-switch/

http://www.pspproducts.com/admin/pdf_files/TC-050M215_191_full.pdf

Here is an inexpensive way to properly connect a generator. No fuse, no muse, safe and let you turn the lights on too.