Portable generator required to have service rated disconnect?

[jwelectric]

It can be a separate building. It can also be same building the generator is located inside of.

In that case then there would be no need for this discussion. What is being discussed is an outdoor generator

The conductors supplied by a generator are not service conductors.

Neither are the branch circuits conductors supplying an AC unit. The conductors supplying the AC unit are not feeders either.

225.36 just says "The disconnecting means specified in 225.31 shall be suitable for use as service equipment."
Nothing in 702 ever required the disconnect mentioned in 225.31. You kind of have to assume they mean you need the disconnect mentioned in 225.31. 225.36 modifies a section we were never directed to in any way.

702 does not require any disconnect. What it says is if the generator has a disconnect that is within sight of the building it must be just like the one mentioned in 225.36
Because these feeders are outside is what brings 225 into the game

edited to add;

702.12 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.

 

[kwired]

In that case then there would be no need for this discussion. What is being discussed is an outdoor generator


Neither are the branch circuits conductors supplying an AC unit. The conductors supplying the AC unit are not feeders either.



702 does not require any disconnect. What it says is if the generator has a disconnect that is within sight of the building it must be just like the one mentioned in 225.36
Because these feeders are outside is what brings 225 into the game

edited to add;

702.12 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 think what you have been saying is the intent of what the NEC wants. All I have been after is the fact that it could have been written in a clearer way.

I also think there is discrepancies in the NEC when it comes to defining separate buildings or structures. The simple bulding and a feeder to another simple building is fairly easy to determine. Now take an industrial process that takes ingredients from several bulk bins or tanks that are located outside the main building with a somewhat complex control system and conveyors or piping to get the ingredients to the main building. If you call these separate structures you complicate how you can connect them to the main building electrical system. If you consider them part of the main building you can run as many circuits as you want between the main building and the bins or tanks, not worry about service rated disconnects, number of supplies, etc. You can run a single supply for power easy enough but what about complex control circuits?

 

[tkb]

I think the idea of a portable generator as a structure is a bit of a stretch. However, I buy into the idea that its in 702 and I didn't see any real exemptions or distinctions made therefore subject to the rules. Assuming its conductors are feeders thereby bringing it into 225 makes sense. Not well written for sure. Be nice if all these things were written into 702 and it would be a whole lot easier to follow.

Any of the generators have an internal disconnect that is service rated?

Are you installing this in NH or MA?

MA has an amendment on 702.11.

702.11. Insert a new 702.11(C) as follows:

(C) Classification of Supply. A generator with a grounded circuit conductor connection as part of its output shall be wired as a separately derived source unless its grounded circuit conductor is not bonded to the frame, or where used to supply a premises wiring system it shall be permitted to be wired as a nonseparately derived source if all of the following conditions are met:

(1) The generator rating does not exceed 15 kw.
(2) The generator is connected through a flexible cord and a cord connector to a flanged inlet.
(3) The flexible cord does not exceed 4.5 m (15 feet) in length.
(4) The flanged inlet connection point is not more than 3.0 m (10 feet) from the main bonding jumper or system bonding jumper for the supplied premises.
(5) The point of connection is marked ?Disconnect cord when generator is not in service.?
(6) Ground-fault protection of equipment has not been installed on any portion of the premises wiring system supplied by the generator.

Informational Note: Current product standards require all portable generators rated 15 kw and below and supplying grounded output circuits to have the grounded circuit conductor connections bonded to the generator frame.

 

[nrp3]

NH

 

[jwelectric]

Now take an industrial process that takes ingredients from several bulk bins or tanks that are located outside the main building with a somewhat complex control system and conveyors or piping to get the ingredients to the main building. If you call these separate structures you complicate how you can connect them to the main building electrical system. If you consider them part of the main building you can run as many circuits as you want between the main building and the bins or tanks, not worry about service rated disconnects, number of supplies, etc. You can run a single supply for power easy enough but what about complex control circuits?

On my dining room table there is an apple and an orange. Are these two the same or are they different?
To compare an industrial installation to a generator is like taking a bite of the apple and then a bite of the orange, we learn that they are different.

A good example is the requirement for GFCI protection for personnel. Nowhere in 210.8 is there a requirement for GFCI protection for maintenance personnel. Can?t find it in 670 either, but guess what NFPA 79 has to say about this. 15.1.2 says that any receptacle that part of any machine either internal or external and is to be used by maintenance personnel must be GFCI protected.

 

[kwired]

On my dining room table there is an apple and an orange. Are these two the same or are they different?
To compare an industrial installation to a generator is like taking a bite of the apple and then a bite of the orange, we learn that they are different.

A good example is the requirement for GFCI protection for personnel. Nowhere in 210.8 is there a requirement for GFCI protection for maintenance personnel. Can?t find it in 670 either, but guess what NFPA 79 has to say about this. 15.1.2 says that any receptacle that part of any machine either internal or external and is to be used by maintenance personnel must be GFCI protected.

Now provide electric power to the apple and to the orange. They look different but the electric power provided to each is likely the same.

 

[kwired]

Large industrial plant or small single family dwelling - if supplied by AC power has same basic rules for supplying power.