5kw genset disconnect

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225.31 is pretty clear that a disconnecting means is required and that .36 requires it to be service rated. You can still have a cord and plug, but the disconnect is still required.

Rick
 
Why does a generator require a disconnect -- it doesn't receive power. But if you're powering a building, then the building needs a disconnect whether the source is a generator or feeder from a utility source. The type of disconnect required would depend on whether you're feeding the building with a feeder or branch circuit.
 
Would a 5kw cord and plug generator require a disconnect as outlined in 225.36?
If you are asking if the disconnect on the generator qualified as the disconnecting means, would it have to be suitable for use as service equipment, i would ask what makes a disconnect suitable for use. Does it need a place to make the bond, does it need a certain interupting rating, does it need to be rated for 60 amps, does it need the listing tag.
Rick
 
I think it depends on how it is being used .. Like when I installed the inlet on the boiler with a 3-way switch as a transfer switch .. violation .. not rated ..

same house same generator lamps and fridge plugged in to the cords supplied by the genny folks .. not a violation.
 
I should have ,.and still might use on of these ,.. certainly next ice storm it would not be a bad idea to have one or two of these around
 
I should have ,.and still might use on of these ,.. certainly next ice storm it would not be a bad idea to have one or two of these around

Yes this is what I am asking about. Will a disconnect as outlined in 225.36 be required to be installed ahead of this unit?

Being that the generator is supplying conductors to the building and they are outside Part II of Article 225 would apply.

702.11 makes reference to this disconnect.

Either way you answer please explain your answer so a lay person can understand.
 
MD do have a name and part number for that disconnect, I have been looking for something like that. Thanks Gus
 
Mike,

This is strictly my opinion and interpretation of the code sections you've cited :

The Gen-Tran power inlet unit shown is an acceptable disconnect means. From the photo shown you can see that there are two methods of disconnecting all ungrounded conductors from feeding power into the building a) the transfer switch at the top right hand corner has an "off" position that will disconnect both utility and generator power, and b) removing the twist-lock plug will disconnect the generator power. IMHO, installing an additional disconnect ahead of this device is over-kill. BTW, from the looks of this unit it's probably only a 30 amp, 240volt inlet so you can't be switching that big a load.

Regards,

Phil

jwelectric said:
Mike Whitt
God answers Knee-Mail.
Are you now "Born Again" or are you still "The Pit Bull " ?
 
This is interesting because of its size and application.

If the generator feeding the plug in transfer switch has a disconnect/breaker on it, and is within site of the building, no additional disconnect required.

If the generator disconnect/breaker is not within site, a 225.36 disconnect is required. It can be either inside or outside.

Ampere rating and voltage of the generator are not mentioned in the requirement.

The transfer switch shown in the post is a furnace 120 volt switch. So technically, if the gen set is located out behind a barrier wall, it would require a 225.36 disconnect inside or outside the building.
Rick
 
All JW mentioned in his OP was that this was a cord and plug connected generator and didn't give us any additional info. My guess is that we're all assuming that this generator is feeding an entire breaker panel inside the building. If that's the case doesn't the main breaker in the panel serve as the disconnect means ?

Usually 5KW generators are portable and not fixed in place. Customarily they are available with a 25' or 50' cords. From my experience the outlet ports on these generators are either 240 V @ 30 amps or 120 v @ 50 amps. But that may have changed depending on the maker. The last one I saw like that was made by Honda. If we can assume, for the moment, that this is the case then there are several disconnects 1) on the generator itself, 2) the cord, 3) the xfer switch and 4) the main breaker. How many more disconnects do we need ?
 
Then let me refine my question.

The generator is a generator that anyone can go to the big box store and buy. It has a transfer switch similar to the one pictured or maybe even a multi switch transfer.

Now the question is:

Even though the generator is connected to the building with a cord and there is some sort of transfer switch in place is the disconnect required for outside branch circuits and feeders that is rated for service equipment as outlined in 225.36 still required?

ARTICLE 225 Outside Branch Circuits and Feeders
225.36 Suitable for Service Equipment.
The disconnecting means specified in 225.31 shall be suitable for use as service equipment.
Exception: For garages and outbuildings on residential property, a snap switch or a set of 3-way or 4-way snap switches shall be permitted as the disconnecting means.

For Optional Standby Systems section 702.11 states the following;
702.11 Outdoor Generator Sets.
Where an outdoor housed generator set is equipped with a readily accessible disconnecting means located within sight of the building or structure supplied, an additional disconnecting means shall not be required where ungrounded conductors serve or pass through the building or structure. The disconnecting means shall meet the requirements of 225.36.

I don?t believe that a cord and plug is rated as service equipment nor do I believe that the small single or multi breaker transfer switches are rated as service equipment either.
 
I think he is talking about is the change to 702.11 that says in order for the equipped disconnect to count it has to meet 225.36.. Which I would hope would be expressed by the people who make them... as I'm not sure what or who decides what " suitable " is for a service disconnect ,.. seems like another NEC overreach to me.

edit to add

A bit late but I think I nailed it
 
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I think he is talking about is the change to 702.11 that says in order for the equipped disconnect to count it has to meet 225.36.. Which I would hope would be expressed by the people who make them... as I'm not sure what or who decides what " suitable " is for a service disconnect ,.. seems like another NEC overreach to me.

edit to add

A bit late but I think I nailed it



I am not sure what would make something suitable as service equipment either but I feel that it has something to do with the bonding of the neutral.

Those portable generators when used with the little transfer switches will have the neutral and grounding electrode bonded in the service of the building. They also have the neutral of the generator bonded to the frame of the generator which now is a violation of the bonding rules outlined by the NEC.
 
Hello Mike.

Well, 702.11 isn't applicable for an "unhoused" portable generator anyways. :wink:


Roger
 
I know that most of the easy tran from reliance were 702 code compliant ,.. not sure what, if any changes were made since 2008...

Iteresting post Roger,.. I was also wondering about the "kill switch" for the engine ...
 
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