K8MHZ
Senior Member
- Occupation
- Electrician
'shall be of copper unless otherwise provided in the Code.' Is pretty self explanatory.
230 specifically allows aluminum for overhead service-drop and underground conductors.
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Aluminum wire
- Thread starter Mr. M
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'shall be of copper unless otherwise provided in the Code.' Is pretty self explanatory.
230 specifically allows aluminum for overhead service-drop and underground conductors.
- Location
- Illinois
- Occupation
- retired electrician
With EMT and 4" square boxes and plaster rings that is not as big an issue.That's correct fill is an issue. You install #12 copper with decora switches and I will tell you it is an tight even if the fill is correct. I used to wire with 12 awg exclusively in a house and when we had to start grounding the switches and use decora devices and dimmers I decided 14 awg was better.
- Location
- Illinois
- Occupation
- retired electrician
That is what the words say, but I have never seen that section read that way.
I wonder why 240.4 (D) (4) is in there then?
stew
Senior Member
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- federal way,washington
see 310 106 (B) in conductors for general wiring section
K8MHZ
Senior Member
- Occupation
- Electrician
Al is allowed for outdoor branch circuits.
K8MHZ
Senior Member
- Occupation
- Electrician
stew
Senior Member
- Location
- federal way,washington
yes it is in 2011 and probably added to clarify 106 B
K8MHZ
Senior Member
- Occupation
- Electrician
I am going to say yes, I saw it somewhere in the code.
Bear with me while I look again.
Well, it's not where I expected it to be. I ran across it today looking for something else and was pretty sure I saw a reference for AL concerning feeders, like min. size or something.
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- Location
- Connecticut
- Occupation
- Engineer
There's nothing in Art. 210 or 225 that says Aluminum is permitted for "outdoor branch circuits."
225.6 does reference Aluminum for "Open individual conductors" in "overhead spans." But the minimum size is #8 Al, so 240.4(D)(4) and (D)(6) can't be referring to 225.6.
230 doesn't specifically allow aluminum for service entrance conductors, only overhead service drops and underground service laterals.
310.106(B) was 310.2(B) (and 310.14) in 2008.
310.2(B) "Conductors in this article shall be of aluminum, copper-clad aluminum, or copper unless otherwise specified." That seems to be the "as otherwise provided" from section 110.5.
K8MHZ
Senior Member
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- Electrician
I concede, and am with you up until 'as otherwise provided'. 310 concerns the construction of the conductors in the entire book. It does not circumvent 110.5, just outlines the requirements for conductors used in the entire book, exceptions and all. 310, in itself, is not an exception.
Furthermore, 110.5 goes on to say that, 'where the conductor material is not specified, the material and sizes given in the Code shall apply to copper conductors. So, where in 220 does it specify conductor material?
I see how 110.5 can be taken the way you stated. I have never read specifically that aluminum could be used as a feeder, but we all know it is used all the time.
In 334.10 it tells me that I can use NM cable in a residence. 334.104 lists aluminum NM cable, but yet in 210 will it tell you that aluminum cannot be used?
It has been my understanding that the NEC has never banned aluminum branch circuits, but amendments have.
Here is an addition to the Texas code:
"(c) The National Electrical Code shall be amended as follows.
(1) Add to Article 310.1 the following statement: "Aluminum and copper-clad aluminum shall not be used for branch circuits in buildings classified as a residential occupancy; aluminum and copper-clad aluminum conductors, of size number 4 AWG or larger, may be used in branch circuits in buildings classified as occupancies other than residential."
(2) Add to Article 110.14 the following statement: "Aluminum and copper-clad aluminum conductors shall be terminated using approved compression-type crimp lugs with approved inhibitors.""
(title 16, Part 4, chapter 70, rule 70-101)
An interesting article:http://www.iaei.org/magazine/2006/01/aluminum-building-wire-installation-and-terminations/
- Location
- Connecticut
- Occupation
- Engineer
It doesn't outline the requirements for all conductors used in the entire book. It outlines the requirements for conductors for "general wiring". 310.1 says that its requirements don't apply to conductors SPECIFICALLY provided for elsewhere in the code.
There is no SPECIFIC conductor in the code for branch circuits, so the conductors for general wiring would apply.
Take for instance, the conductors in a flexible cord or in a fixture wire. These are specific conductors, not conductors for general wiring. Article 310 wouldn't apply to these (Arts. 400 & 402) would. 110.5 would require that these conductors be copper, unless there were other provisions in the code. I don't see anything that provides for aluminum for the conductors in flexible cords.
hurk27
Senior Member
- Location
- Portage, Indiana NEC: 2008
It doesn't that is the reason for the last part of 110.5 and the FPN
The same thing with 210, table 210.24 gives us sizes for copper but no where is copper specified, and even note 1 to the table indicates if a conductor of another material is used we need to adjust the size.
K8MHZ
Senior Member
- Occupation
- Electrician
I disagree. Since no conductor material is specified, 110.5 says it has to be copper. If 310 precluded that, there would be no need for 110.5.
So for a 50 amp branch circuit, you install copper?
K8MHZ
Senior Member
- Occupation
- Electrician
The FPN addresses the sizing, and only the sizing for Al where it is allowed. It does not say, no matter how you read it, that it is allowed in every instance.
K8MHZ
Senior Member
- Occupation
- Electrician
Indoors, yes. In fact, I have never pulled Al for an indoor branch circuit of any size.
Not criticizing, just curious with that last question. Anything bigger than 10 (usually), I use Al. Occasionally I will use 8 cu if the price is right...
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