Generator bonded neutral (safety issue)

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Old 08-19-13, 10:53 AM
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Generator bonded neutral (safety issue)

In my application I have a fused main disconnect between the meter and the service panel which is actually considered the main panel and has the neutral and ground bonding there. My breaker panel is actually considered a sub-panel and does not have bonded neutral and grounds. If this is the panel that I will be feeding with my generator (using a generator interlock) does this issue still apply?

Regarding this thread.....

http://www.doityourself.com/forum/el...d-neutral.html
 

Last edited by lawrosa; 08-19-13 at 12:21 PM.
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Old 08-19-13, 12:23 PM
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Moved post to own thread..................
 
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Old 08-19-13, 05:20 PM
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It is best to use a neutral-switching (three-pole) transfer switch, NOT a circuit breaker interlock.
 
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Old 08-19-13, 06:21 PM
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I understand but the question was that a while back you offered a solution, albeit not exactly code, by not connecting the ground wire on the inlet recepticle. What I wanted to know was since the panel I'm connecting to does not have bonded netural / ground does the same work around apply?
 
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Old 08-19-13, 07:01 PM
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If you use an in-panel interlock and backfed breaker pair for your generator, then the "bonding issue" will still be there, exactly the same as if the home neutral-ground bonding was in that panel.

With a (3 pole, neutral switching) transfer switch and the home neutral-ground bonding upstream (in a separate box or panel with the main disconnect) you do not have the "bonding issue."

In my opinion, neutral-ground bounding both in a generator supplying a home and in or near the panel fed by the generator is not really a safety problem.
 
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Old 08-19-13, 07:59 PM
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I agree with Allan, the point of bonding between the neutral and the equipment ground has not changed simply because you will be feeding a sub-panel. If your generator has a neutral-ground bond then do not connect the equipment ground in the interconnect cable. If the generator does not have a neutral-ground bond then you DO connect the equipment ground in the interconnect cable.
 
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Old 08-20-13, 07:37 AM
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Thanks guys, that was the information I was looking for.
Frankly, I'd love to go with a 3 pole transfer switch but I can't afford that kind of coin. Does anybody have a source for reasonably priced switches?
 
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Old 08-20-13, 07:52 AM
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In my opinion, neutral-ground bounding both in a generator supplying a home and in or near the panel fed by the generator is not really a safety problem.
Creates a parallel path for neutral current from what I read.

If the feeder neutral faults open, all neutral current will flow on grounding conductors and not trip any over-current devices.

Neutral current on grounding conductors can create voltage gradients with shock potential on grounded non-current-carrying metal parts.


http://cumminspower.com/www/literatu...ingAC-2-en.pdf
 
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Old 08-20-13, 07:57 AM
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Oh and these are about $100 bucks... Turns your transfer switch into a neutral switching transfer switch...


Gentran Corporation: Generator Transfer switches for home & business
 
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Old 08-20-13, 08:31 AM
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Mike.... I believe that kit only works with a separate emergency power panel. That relay could never switch a full sized neutral.

By a separate panel, I mean the generator type sub panels with like 10 circuits.
 
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Old 08-20-13, 09:33 AM
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I believe that kit only works with a separate emergency power panel.

I read it quickly...Looks like a new product since I never saw it before.. Looks like it says what it does..
 

Last edited by lawrosa; 02-13-14 at 02:01 PM. Reason: roemoved broken link
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Old 11-27-14, 01:02 PM
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Regarding the referenced single circuit (furnace) transfer switch, if one were to use this with a portable generator, would the internal ground of the generator be sufficient or would the portable generator need to be grounded to earth?
 
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Old 11-27-14, 04:33 PM
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Old thread has run its course. Please start new..

Thanks....
 
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