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According to the GE Spec-Setter TM datasheet their AC disconnects are comprised of three varieties: fusible, no fuse, non-automatic.

A GE diagram on that datasheet for their "fusible" disconnects shows a BONDED NEUTRAL. Since the NEUTRAL is supposedly only bonded once per system, usually in the main breaker panel, why would the GE disconnect with fuses require that you BOND the NEUTRAL?

It is known that many HVAC systems only require 240 V AC, and a ground, so in those cases there is no NEUTRAL conductor in their disconnects, which suggests that these GE fused disconnects that require BONDED NEUTRAL are designed for the case where they are controlling the power going to a combination 120/240 utilization equipment.

And, though outside the scope of the question, what does GE mean by non-automatic disconnect? Their diagram appears to show a ganged 2-pole switch.

I found the GE datasheet as a PDF at the buy.wesco.com website.

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  • If you could edit in a link to the data sheet you're looking at, it would help us all be on the same page. May 14 at 17:55
  • I agree with the data sheet is needed. if a “main disconnect as a fused disconnect can be” it would require a bonded neutral, I put in small separately derived systems regularly and it is common for this to be the main. but as a safety disconnect bonding would be a code violation.
    – Ed Beal
    May 14 at 18:00
  • From this PDF library.industrialsolutions.abb.com/publibrary/checkout/… page 18, it says "Bonding strap can be used to ground factory installed neutral for service entrance applications" I don't have code experience that the gurus here have, but it appears these devices can be the first device in the electrical service after the meter, thus the place where ground and neutral would be bonded. May 14 at 18:00
  • You missed the meaning of the term service entrance this is a main disconnect as I mentioned in my comment.
    – Ed Beal
    May 14 at 18:03
  • @Ed Beal This question is about AC disconnects, or HVAC disconnects, not a MAIN disconnect. I could not find the term "safety disconnect" in the NEC. You say that "as a safety disconnect bonding would be a code violation." Could you reference that section of the NEC?
    – Guiermo
    May 14 at 18:33

1 Answer 1

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A fused disconnect can be a main disconnect and if used as a main or service entrance disconnect the neutral is required to be bonded by code.

A non fused or safety disconnect requires over current protection so it would not be the main and it would be a code violation to bond beyond the main service entrance panel, the 99 code update made this change as I remember.

If the fused disconnect is used as a safety disconnect it would be a code violation to bond at this point.

So the difference is the wording “service entrance” requires bonding

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    This is it. People think that services are only for houses. They are also for railroad crossing gates, weather stations, guard shacks and the like. May 14 at 18:47
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    @Guiermo Well the industry is full of that, for instance "mobile home feeder" which is used for lots of NON-mobile home uses. May 14 at 20:30
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    Actually anytime a transformer is used it can be a service 1:1 or 2:1 more common in commercial or industrial sites as the transformer creates a separately derived system and the reason a fused disconnect has the instructions a safety disconnect is not required to be fused.
    – Ed Beal
    May 14 at 21:30
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    Actually a generator (gas, diesel, wind or solar) or a transformer ARE separately derived systems and the secondary of the transformer is required to have the neutral ground bond as it is a separately derived system as defined by code although rare I have provided a service to a residence (120/240) from a 480 3 phase industrial system where there was isolation required.I have no idea who Ryan Jackson is and any one can make a video there are many on the internet from non licensed persons
    – Ed Beal
    May 15 at 22:16
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    @Guiermo Youtube is full of idiots, but Ryan is talking about the normal use-case in a pre-solar pre-"cut the cord" everyone getting all their electric from the utility and just crying in the dark when the power goes out. Now that we have options, services are popping up all over. Yet still, a railroad crossing gate will take a disconnect just like that. May 16 at 1:09

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