5kw genset disconnect

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iwire said:
Mike, there is no way that generator is only designed to used to supply a building and the manual says no such thing.
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From the manual

Connections for standby power to a building electrical system must be
made by a qualified electrician. The connection must isolate the
generator power from utility power, and must comply with all
applicable laws and electrical codes. A transfer switch, which isolates
generator power from utility power, is available through authorized
Honda generator dealers (see page 43 ).​


Then we can't forget what the NEC has to say​

250.34(C) Grounded Conductor Bonding. A system conductor that is required to be grounded by 250.26 shall be connected to the generator frame where the generator is a component of a separately derived system.
FPN: For grounding portable generators supplying fixed wiring systems, see 250.20(D).​

Now for the real question,
In your opinion does this generator require a disconnect as outlined in 225.36?​
 
If the generator is supplying the building it needs a disconnect at the building or in sight from the building and this disconnect must be service rated.
 
jwelectric said:
From the manual
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Yes Mike I read that, it still does not restrict the genset to that use.

IF I connect it to a buildings electrical system that section from the manual would apply.

Now for the real question,
In your opinion does this generator require a disconnect as outlined in 225.36?
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Without a doubt that is what the words say. So why are you asking?

Now have I every seen it enforced that way for cord and plug connected generators, nope, never.

Is it worth putting in a proposal to change it? Probably
 
Thank you Don for your answer.

I ask this question due to a discussion we were having concerning one of those four circuit transfer switches and a cord and plug generator.

The generator being used has the neutral bonded to the frame and in my opinion this would disallow the type transfer switch that was being used.

Along comes the inspector Friday morning and asked for a disconnect be installed as outlined in 225.36 ahead of the transfer switch being used.
I had never saw a disconnect being used but had to agree with the inspector due to a lack of information being found in the NEC to the contrary.

I figured I could get some quick responses from this site but it turned into a discussion of bonding the generator or not bonding the generator.

The problem was solved yesterday as the home owner decided to install a larger generator and install a proper transfer switch for the building but the question is still a good question concerning the requirement of 225.36

Edited to add:

Thank you also Bob
 
Ok, how about this...

Does the cord and inlet of a cord-connected generator fall under this definition for an outside feeder:

"225.1 Scope. This article covers requirements for outside branch circuits and feeders run on or between buildings, structures, or poles on the premises; and electrical equipment and wiring for the supply of utilization equipment that is located on or attached to the outside of buildings, structures, or poles."

If not, is a transfer switch a disconnecting means suited for the purpose of disconnecting the portable generator from the wiring of the building?

If so, and the transfer switch is at "a readily accessible location nearest the point of entrance" to the building (inside or out), then 225.36 wouldn't apply?
 
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SAC said:
Ok, how about this...
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SAC said:
Does the cord and inlet of a cord-connected generator fall under this definition for an outside feeder:
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There are four different type of conductors mentioned in the NEC. These conductors must fit into one of these types.

Branch Circuit. The circuit conductors between the final overcurrent device protecting the circuit and the outlet(s).

Feeder. All circuit conductors between the service equipment, the source of a separately derived system, or other power supply source and the final branch-circuit overcurrent device.

Service Conductors. The conductors from the service point to the service disconnecting means. (Let?s see what the service point is just for kicks)
Service Point. The point of connection between the facilities of the serving utility and the premises wiring.

And the fourth we can rule out completely - tap conductors.

I think that we can also rule out service conductors as they connect to the utility company.

This leaves us with only two to choose from and both are mentioned in Article 255.

I would think that by definition they would be feeders. ?conductors between other power supply source and the final branch-circuit overcurrent device.?

Now if these conductors are installed outside then we are well on our way to adhering to Article 225 Part II.

These conductors leave something and land at a separate building (the building being served and what 225 is addressing in Part II).

You can see that every section of Part II is addressing the building being served and not where the conductors originate from.

Yes these conductors can land in a transfer switch as long as the transfer fulfils the requirements of 225.36.

Yes the disconnect on the generator that is required by 445.18 can be the disconnect required by 225.36 as long as it complies with 702.11
 
So an extention cord can be a feeder , or a branch circuit ??

The conductors land in cord caps
 
One more thing , and Roger pointed it out,.. 702.11 applies to housed outdoor generators ..
 
M. D. said:
So an extention cord can be a feeder , or a branch circuit ??

The conductors land in cord caps
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Yes.
The cord "extends" the branch circuit or feeder thus the expression "extension cord"

M. D. said:
One more thing , and Roger pointed it out,.. 702.11 applies to housed outdoor generators ..
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So nothing on a portable generator could replace the requirement found in 225.36 and a disconnect that is rated as service equipment would now be required unless you can find something that states it is exempted.
 
M. D. said:
An extention cord starts where the branch circuit ends,..
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Well I suppose that you could look at it like that but it still wouldn't change the fact that you have conductors coming from one place on the outside of a building and then entering the building that originated somewhere other than the building that is being supplied.

Of course using your application I could send conductors down across the yard to a building in the corner of the lot and land them in a receptacle and then plug in a cord and get by with the disconnect at that building.
Now according to your thinking this would be code compliant.

Then again we still have the definition of feeders that clearly state ALL CONDUCTORS but then again maybe cords don?t have conductors.

Not trying to be factious just trying to understand your reasoning.
 
I don't say that,... the NEC says that in the definition

I'm just trying to wrap my brain cells around this ,.. I have installed a few of those small transfer switches for use with portable generators,.. I have seen, in ROPs,.. that type discussed in regard to other issues ,.. can't remember what issue,.. at the moment ...

IMO I can run an extension cod to an inlet on my shed an have a recognized wiring method connected to it and no disconnect is required.

I read somewhere that there have been 10 million portable generators sold and many ,..many,.. of these incorporate those small type transfer switches ..I know that numbers do not make for compliance ,. but this is a biggie.

I appreciate this discussion and I am not saying that I know that it needs not be service rated but I do know that 225 is for branch circuits and feeders and I'm not certain those definitions fit,.. and if it is un-housed 702.11 does not seem to apply.
 
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How about this requirement: "225.39(C) One-Family Dwelling. For a one-family dwelling, the feeder disconnecting means shall have a rating of not less than 100 amperes, 3-wire."

Sort of overkill for a 5kw genset. The linked transfer switch was only rated @ 20A.
 
SAC said:
How about this requirement: "225.39(C) One-Family Dwelling. For a one-family dwelling, the feeder disconnecting means shall have a rating of not less than 100 amperes, 3-wire."

Sort of overkill for a 5kw genset. The linked transfer switch was only rated @ 20A.
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SAC if your picking up the entire dwelling, then C applies, if its for the furnace transfer switch, A applies, if its any thing else D applies.

Rick
 
So if one has a 5KW genset that is used to feed the main panel through a interlocked main and back-fed breaker (manual load shedding by only enabling selected branches), there needs to be a disconnect rated for 100A on the feeder from the genset?
 
SAC said:
So if one has a 5KW genset that is used to feed the main panel through a interlocked main and back-fed breaker (manual load shedding by only enabling selected branches), there needs to be a disconnect rated for 100A on the feeder from the genset?
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The manual backfeed breaker can be the required disconnect. The requirement states that it can be located outside or inside closest to the entry of the conductors.
Rick
 
O.K. it is a violation for a cord to run through a door or window ,. so my wife likes to garden at night and the garden shed is dark,. so I install a version of this thing in the proper boxes and covers and plug it into my outside gfci on the house ,.and when she is done she unplugs the cord and puts it away.. Is a service rated disconnect required ??

p36632-PowerBridge_main.jpg
 
On residential property, a snap switch would be allowed for out buildings and garages. (225.36 exception)

Rick
 
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