Generator X-fer switch question

[hillbilly1]

Finally had a chance to look over these code references, 702.11 does not require it to be service rated, it only requires that it be readily accessible and within sight of the building or structure supplied. which the generator install picture complies with. The one part of article 702 that this install did not comply with is 702.8, Inspector must have missed that one.
After reading article 225, I do not think it is the intent of this article to include generators, as in 225.2 does not include any articles on generators. Also the wording in the scope is ....for the SUPPLY of utilization equipment.... It is a good practice to have a disconnect next to the service because it makes it easy on the firefighters to kill building power, but when installing large generators, it is not practical. I knew there was a reason I mentioned Mecklinberg county NC, in a previous post, I remember know that it was the only jurisdiction that required a main before going into the building, the key switch was not acceptable to there code compliance department. The toughest one I ever did was Beaver Creek Ohio, and they did not require it.

 

[iwire]

I just know the switches that come through the door with UL listings on them and only one disconnecting means.

Are those particular units marked ??SUITABLE FOR USE AS SERVICE EQUIPMENT???

 

[jwelectric]

Finally had a chance to look over these code references, 702.11 does not require it to be service rated, it only requires that it be readily accessible and within sight of the building or structure supplied. which the generator install picture complies with.

I am sorry but the generator in the picture I posted the generator disconnect is NOT within sight of the building.
For those who thinks that the generator is what should be insight of the building the section was reworded for clarity in the 2008 cycle. It even goes on to clarify that the disconnect on the generator when in sight of the building must conform to 225.36

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.

After reading article 225, I do not think it is the intent of this article to include generators, as in 225.2 does not include any articles on generators.

225 does not address generators but it does address those conductors that come from the generator to the building and the building is separate from the generator so the total of 225 applies to the conductors after they leave the generator.

Also the wording in the scope is ....for the SUPPLY of utilization equipment....

I do believe you left out all the important stuff at the beginning of that sentence

It is a good practice to have a disconnect next to the service because it makes it easy on the firefighters to kill building power, but when installing large generators, it is not practical. I knew there was a reason I mentioned Mecklinberg county NC, in a previous post, I remember know that it was the only jurisdiction that required a main before going into the building, the key switch was not acceptable to there code compliance department. The toughest one I ever did was Beaver Creek Ohio, and they did not require it.

As you clearly state in the statement above one of them must be wrong. I stand on the side of Mecklenburg County as they are correct as outlined in the NEC.

 

[hillbilly1]

So the generator pictured does not supply the building the service is on? if so then I agree with you on that. Also what about the compliance with 702.8? Since this generator feeds another building, the sign is on it?

 

[jwelectric]

So the generator pictured does not supply the building the service is on? if so then I agree with you on that. Also what about the compliance with 702.8? Since this generator feeds another building, the sign is on it?

Yes the generator supplies the disconnect that is rated as a service disconnect on the side of the building in compliance with 225.36.

The disconnect on the generator in there because of
445.18 Disconnecting Means Required for Generators.
Generators shall be equipped with disconnect(s), lockable in the open position, by means of which the generator and all protective devices and control apparatus are able to be disconnected entirely from the circuits supplied by the generator

702.11 will allow this disconnect to fulfill the requirement in 225.26 Where the disconnect is readily accessible and the disconnect is in sight of and is also rated as service equipment.

Should the 445.18 disconnect not be readily accessible or in sight of or service rated then a disconnect will be required to be installed that does comply with all three of these.

The wiring from this generator to the building must comply with, 702.3 Application of Other Articles. Except as modified by this article, all applicable articles of this Code shall apply.

The conductors coming from the generator are outside so they must comply with, ARTICLE 225 Outside Branch Circuits and Feeders

Unless of course these conductors meet the definition of service conductors, Service Conductors. The conductors from the service point to the service disconnecting means.
I just don?t think that fit that definition. I think that they would fit better here, 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.

This generator is not part of the building nor is it inside the building so once the feeders reach the building they must comply with Part II of 225.


The sign is just beside the disconnect handle on that disconnect.

 

[hillbilly1]

225.30 (A) is an interesting read also, I had never thought about it but there is more than one feeder to the generator. You have block heaters, battery chargers and the like. That section allows more than one feeder for those listed systems. I will have to talk to the engineers that draw up the blueprints for these installs and see why they do not call for it (the disconnect) on any of the jobs. Their seems to be a lot of engineers missing this, as we work with a lot of different ones.

 

[360Youth]

Are those particular units marked ??SUITABLE FOR USE AS SERVICE EQUIPMENT???

Yes. I will double check and make sure I am not wrong.

 

[360Youth]

Mike is correct, it is not optional. UL requires a service rated transfer switch to be cable of disconnecting both sources.

I just know the switches that come through the door with UL listings on them and only one disconnecting means. I may have to go read some old paperwork and stand corrected, but I have installed quite a few and did the start up on many others installed.

I am a little slow in tracking this down, but it took me a while to find one of the old switches for model info . These (see section 1.2) have been installed on several jobs, by both us and other ECs that we have done start-ups for, and been accepted as the service disconnecting means. Now the arguement may remain that an additional disconnecting means for the generator where it enters the building may also be required, but, where the generator is located within sight of the service, I have never had an inspector interpret the install in such a manner. But my original point of contention was that a service rated ATS must disconnect both sources. Geneac has a new 200 amp ATS with load center, but it is a fairly new product that there has not been much literature out on it yet.