Detached Garage & 3way

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1793

1793

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Louisville, Kentucky
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Inspector
I have a job where I am re-feeding a detached garage with new underground conduit. I am setting a panel in the garage and I need to reestablish 3way switching for some of the outside lighting on the garage.

My question is: "Can I use the panel in the garage as a J-box for the 3way or should I pull through the panel to the switch box?" I ask because I would like to use the same conduit for the feeder to the garage for the 3way switching.

Thanks
 
You can use the panel to splice but how will you deal with 225.30 if the other 3 way is at the house. Just for your info.... The 2011 NEC allows this install but the 2008 does not.
 
jxofaltrds said:
Doesn't 225.30(D) allow this?
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I am not sure that is pertaining to this or not. Since the 2011 changed a bit it did not change (D)-- the heading of (D) is different characteristics-- I would not call a 3 way a different characteristic but I may be wrong.
 
With the wording:
(D) Different Characteristics. Additional feeders or branch circuits shall be permitted for different voltages, frequencies, or phases or for different uses, such as control of outside lighting from multiple locations.
possibly it is a stretch, but I know a lot of inspectors that will allow a 3-way using this section.
 
augie47 said:
With the wording:
(D) Different Characteristics. Additional feeders or branch circuits shall be permitted for different voltages, frequencies, or phases or for different uses, such as control of outside lighting from multiple locations.
possibly it is a stretch, but I know a lot of inspectors that will allow a 3-way using this section.
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Augie, How is that a stretch? The words are right there aren't they or am I missing something?
 
Break the sentence apart:

(D) Different Characteristics. Additional feeders or branch circuits shall be permitted ......................

for different voltages, frequencies, or phases ..................................

or for different uses, such as control of outside lighting from multiple locations.


Now take out the middle part and read that.

(D) Different Characteristics. Additional feeders or branch circuits shall be permitted for ............ different uses, such as control of outside lighting from multiple locations.

You have power fed to the garage for the lights and receptacles and whatever else out there... that's one 'characteristic'. The 3-way switch loop is another 'characteristic'.
 
infinity said:
Augie, How is that a stretch? The words are right there aren't they or am I missing something?
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maybe just a small stretch :)
unless you consider the garage (outdoor lighting" one must say it's "similar"..
 
Dennis Alwon said:
I am not sure that is pertaining to this or not. Since the 2011 changed a bit it did not change (D)-- the heading of (D) is different characteristics-- I would not call a 3 way a different characteristic but I may be wrong.
Click to expand...
Well, reading 2011 NEC 225.30(D) note my highlight:
2011 NEC 225.30 Number of Supplies
(D) Different Characteristics. Additional feeders or branch circuits shall be permitted for different voltages, frequencies, or phases or for different uses, such as control of outside lighting from multiple locations.
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A 3 way is a "different use" and "shall be permitted" under the heading of "Different Characteristics, seems to me.
 
So why the change in 2011.


2011 NEC said:
225.30 Number of Supplies. A building or other structure that is served by a branch circuit or feeder on the load side of a service disconnecting means shall be supplied by only one feeder or branch circuit unless permitted in 225.30(A) through (E). For the purpose of this section, a multiwire branch circuit shall be considered a single circuit.
Where a branch circuit or feeder originates in these additional buildings or other structures, only one feeder or branch circuit shall be permitted to supply power back to
the original building or structure, unless permitted in 225.30(A) through (E).
For the purpose of this section, a multiwire branch circuit shall be considered a single circuit.
Click to expand...
 
al hildenbrand said:
Well, reading 2011 NEC 225.30(D) note my highlight: A 3 way is a "different use" and "shall be permitted" under the heading of "Different Characteristics, seems to me.
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My problem is the heading "different characteristics" I do not see a 3 way as a different characteristic. If the circuit was from a different system such as a 277V system rather than a 120/240 that would be understandable.
 
Dennis Alwon said:
My problem is the heading "different characteristics" I do not see a 3 way as a different characteristic. If the circuit was from a different system such as a 277V system rather than a 120/240 that would be understandable.
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The way the sentence is written for different uses is considered a different characteristic.
 
Dennis Alwon said:
My problem is the heading "different characteristics" I do not see a 3 way as a different characteristic. If the circuit was from a different system such as a 277V system rather than a 120/240 that would be understandable.
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So would a characteristic of a conductor be whether it's always energized or not?


The feeder to the garage lights/receps is always energized. The switching loop always changes, depending on the switches.
 
Dennis Alwon said:
My problem is the heading "different characteristics" I do not see a 3 way as a different characteristic. If the circuit was from a different system such as a 277V system rather than a 120/240 that would be understandable.
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Given the wording of the section I think the heading is irrelevant.
 
I think it is important to focus on the listed "different characteristics":
  1. different voltages
  2. different frequencies
  3. different phases
  4. different uses
Not only does the passage 225.30(D) say different uses but it goes on to say such as which, in my opinion, includes all manner of switching setups for lighting, of which, switching the yard illumination between the garage and the house is one of, if not the, most common.
 
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Say, I am a shade tree mechanic and I have an OPEN sign that is cord and plug illuminated, and that I hang the OPEN sign inside the garage where it shines out through a window. Now, the garage is supplied by a feeder, or a branch circuit, that supplies the bulk of the garage wiring system.

However, I decide I need the control of the OPEN sign receptacle to be both inside the house and inside the garage. I then make use of another branch circuit at the house to control the illumination of the sign.

This is a "different use" than the supply to the building and is allowed then as a different characteristic. While it is a supply to the OPEN sign receptacle, it is not the supply to the building.
 
Al I get you but if you use that argument then I could run a feeder to a panel and a feeder to the heating system since they have different uses. I could add a 3 way switch to control the panel from different location thru a contactor and call it good according to (D). Something is not quite right here.

I admit I have done 3 ways from different structures and I honestly don't see a big issue esp. if feed to the 3 way originates at the separate structure.

I still am not sure why the wording was changed in 225.30. It seems you don't need (D) as long as it is fed from the additional sep. structures.

Bob I don't agree with you that the heading is irrelevant. It is totally relevant and that's why they are there. I am not saying you all are wrong but I am trying to understand where the CMP is coming from.
 
Dennis Alwon said:
Al I get you but if you use that argument then I could run a feeder to a panel and a feeder to the heating system since they have different uses. I could add a 3 way switch to control the panel from different location thru a contactor and call it good according to (D). Something is not quite right here.

I admit I have done 3 ways from different structures and I honestly don't see a big issue esp. if feed to the 3 way originates at the separate structure.

I still am not sure why the wording was changed in 225.30. It seems you don't need (D) as long as it is fed from the additional sep. structures.

Bob I don't agree with you that the heading is irrelevant. It is totally relevant and that's why they are there. I am not saying you all are wrong but I am trying to understand where the CMP is coming from.
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From a pure technical standpoint, I don't believe 225.30(D) even matters for this. As you say, headings matter, and 225.30 is "Number of Supplies". A 3-way switch-loop from additional building to the originating building and back is not a "supply". It would have to power a load at the originating building for it to be a "supply" there, which it does not, and it does not constitute a second "supply" when it returns to the additional building for that is where the "building supply" originated. :roll:;):D
 
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