Where can I buy 10/2 Al wire?

[runderwo]

I want to buy a length of 10/2 Aluminum branch wire for repair in an aluminum wired house... even the electrical shops around here won't sell in qty less than 250 feet. All I need is something like 3 feet of it.

[got_nailed]

Can you use copper to AL wire buts?

[runderwo]

I have a 4 wire 10 gauge Al junction that I need to add a 12 gauge copper wire to for a total of 5 wires. There is nothing that will connect the 5 dissimilar wires and meet code. So I need to use a small Al jumper wire (use a Scotchlok B/G nut for the 5 10awg Al wires) and then pigtail the copper to that single wire instead. Only problem is, I can't find a small length of Al 10awg wire anywhere.

[runderwo]

I guess I hoped somebody on here would see this post and sell me a piece...

[runderwo]

It was the first place I looked when I realized that no supply house would sell it to me locally... no luck there either...

[Bob NH]

You have a situation that probably doesn't have a good "code compliant" solution.

If I had to solve the problem I would get an uninsulated CU/AL rated connector that you can find at HD. Get the smallest connector that is large enough to put all 5 stripped wires through one hole. Then I would strip the conductors (4 Al and 1 Cu) long enough to go through the connector to engage BOTH screws of the connector. Clean the aluminum and apply NOALOX or other antioxidant, insert the conductors into the connector (you can use either or both ends as convenient for wire routing) and tighten BOTH screws.

Then I would insulate it with rubber and plastic tape or a piece of heavy-duty shrink tubing. I have used the kind of shrink tubing that is used when installing submersible pumps. It contains a meltable sealant and usually comes in a package of 4 with butt connectors. Look in the plumbing section where they sell submersible pumps.

[runderwo]

Could you post a google images result for the type of connector you are talking about? I understand your method if the connector is what I'm picturing in my mind.

I guess the other option is to install an extension or two on top of the box to give me more room, pigtail all 4 aluminum wires, and then nut the 5 resulting copper wires together. Ugh...

[Bob NH]

Could you post a google images result for the type of connector you are talking about? I understand your method if the connector is what I'm picturing in my mind. .

I can't find a picture but it is just a short hollow metal bar with a set screw near each end to clamp the wires. My suggestion is to just put the aluminum and copper wires through under both screws for double clamping of all wires.

I have seen them in the same place that they have lugs. You could put all of the wires through a lug but you would have only one set screw to hold them. I would use the connector for more certain clamping.

[runderwo]

O.M.G. I don't think there are words for the level of unholiness that is stuffed in that box now :eek: but I'll try anyway.

I pulled some slack out of some existing Al wire in the house and cut off about 6 inches, enough for two jumper wires to git er dun

The panel wiring is 10awg Al. There are 2 daisychain fixtures wired with 10awg Al and 1 daisychain wired with 12awg Cu. There is a wall switch for the fixture that hangs off this box that is wired 10awg Al. The fixture itself is 3 separate lights (9 wires) of 14awg stranded Cu.

Here goes...

panel hot 10awg Al + 2 daisychain fixture hot 10awg Al + 1 wall switch send 10awg Al + jumper hot 10awg Al = Scotchlok B

panel neutral 10awg Al + 2 daisychain fixture neutral 10awg Al + jumper neutral 10awg Al = Scotchlok B

panel ground 10awg Al + 2 daisychain fixture ground 10awg Al + jumper ground 10awg Al = Scotchlok G

jumper ground 10awg Al + daisychain fixture ground 12awg Cu + this fixture ground 12awg Cu = Alumiconn

jumper hot 10awg Al + daisychain fixture hot 12awg Cu = Alumiconn

jumper neutral 10awg Al + daisychain fixture neutral 12awg Cu + this fixture neutral jumper 12awg Cu = Alumiconn

wall switch return 10awg Al + this fixture hot jumper 12awg Cu = Alumiconn

this fixture hot jumper 12awg Cu + fixture assembly hot 14awg stranded Cu = Scotchlok R

this fixture neutral jumper 12awg Cu + fixture assembly neutral 14awg stranded Cu = Scotchlok R

Unbelievable... I truly pity the next guy.

[hj]

I cannot imagine anyone even having an aluminum wire as small as #10.

[runderwo]

Apparently I'm "lucky" since I'm told in the 70's some branches were wired #12 AL which can only carry 15 amps safely... but with a 20 amp breaker installed anyway...

[hj]

I was referring to anyone having a piece of 10/2 aluminum wire to sell you now. Back in the 70's there was 12/2 and 14/2 aluminum, but once residential small gauge aluminum wire was outlawed there was almost no reason to even produce it.

[jwelectric]

I was referring to anyone having a piece of 10/2 aluminum wire to sell you now. Back in the 70's there was 12/2 and 14/2 aluminum, but once residential small gauge aluminum wire was outlawed there was almost no reason to even produce it.


Has never been outlawed and is still being produced except it was never allowed to use 14/2 Al conductors

[runderwo]

I think in some local areas it may beagainst code to use it, but the NEC still allows it? Looks like there is new construction using copper-clad aluminum today... not solid aluminum like I have.

[Alectrician]

Use 12/2 copper with TIGHT wirenuts.

Nothing wrong with that. It's done every day.

CAREFUL when you strip the Al wire. Use the #10 slot in the strippers. If you ring the wire even a little bit, it will snap off in the nut.

[Speedy Petey]

Use 12/2 copper with TIGHT wirenuts.

Nothing wrong with that. It's done every day.

CAREFUL when you strip the Al wire. Use the #10 slot in the strippers. If you ring the wire even a little bit, it will snap off in the nut.What are "tight" wire nuts? Are they approved for AL to CU splices?

[hj]

I assume he means TIGHT as in turn them as much as possible. But that did not stop the old systems from deteriorating,a nd loosening, because of different rates of expansion and contraction.

[Speedy Petey]

I truly hope he does not mean that. If so he should NOT be giving advice such as this on a public board. Not unless he wants to burn down some houses.

There are few ways to splice small AL conductors to copper. A regular wire nut is NOT one of them!

[runderwo]

Supposedly, a scotchlok nut with a flame-free antioxidant, the wires scraped and pre-twisted, and with no more than 4 wires to a nut, is considered a good connection -- if not UL listed. But definitely do not use any regular wire nut that isn't a "spring" type, or those UL listed Ideal purple nuts you see at the store... they readily flame out.

I just use the Alumiconn lugs to remove any question, but they only take 3 wires, they are bigger than a wire nut, quite a bit more expensive due to the patent, and proper tightening of the lugs requires a torque screwdriver. Though I would suggest a torque screwdriver when tightening any AL wire connections such as switches and outlets, because it removes the margin for error that exists when you tighten by 'feel'.

[Bob NH]

Split bolts rated for AL/CU are available in a wide range of sizes. Insulate with tape.

There is also a nice terminal strip that is rated for up to 30 Amps with for wire up to #10 that would work with "1 to 1" connections. It can be cut to length. I could not read the listings molded into the insulation because the print is too small and no contrast. http://www.radioshack.com/product/index.jsp?parentPage=search&summary=summary&cp=&productId=2103232&accessories=accessories&kw=terminal+strips&techSpecs=techSpecs&currentTab=summary&custRatings=custRatings&sr=1&features=features&origkw=terminal+strips&support=support&tab=techSpecs

[jwelectric]

First.....You skipped a question Pete. What did you use in the 70's to make AL connections ?.

According to the 1975 code cycle on page 18 in section 110-14 when making connections between copper and aluminum the use of an approve connector was called for. In the 1968 code cycle it was in the same section, the second paragraph but on page 15.
In the 1962 cycle the rule is found on page 27 in section 110-13 second paragraph.

Maybe your speed comes from your lack of knowledge of what you are doing. It has NEVER been appropriate to splice copper and aluminum together without the use of the proper fitting.


You are trying to tell me that wire nuts won't make a proper al/cu connection? NO!!! I am not “trying” to tell you, I AM TELLING YOU that the use of a regular wire nut to splice copper to aluminum is an improper connection.

[ked]

Why not rewire with copper wire?

[Speedy Petey]

You keep telling yourself that.

It's great to see a "professional" electrician condoning an illegal and unsafe installation. :rolleyes:

Do you even own a code book?

110.14 Electrical Connections
Because of different characteristics of dissimilar metals, devices such as pressure terminal or pressure splicing connectors and soldering lugs shall be identified for the material of the conductor and shall be properly installed and used. Conductors of dissimilar metals shall not be intermixed in a terminal or splicing connector where physical contact occurs between dissimilar conductors (such as copper and aluminum, copper and copper-clad aluminum, or aluminum and copper-clad aluminum), unless the device is identified for the purpose and conditions of use. Materials such as solder, fluxes, inhibitors, and compounds, where employed, shall be suitable for the use and shall be of a type that will not adversely affect the conductors, installation, or equipment.

[jwelectric]

Hey Pete, here is what it said in the 1968 code cycle. Remember when these houses were being wired?
When AL wire was being installed for several years in the 70's, wire nuts were used at every splice.
I think this was after what was printed in the 1968 code cycle

http://i3.photobucket.com/albums/y63/jwelectric/110-141968.jpg

.

[Speedy Petey]

Looks familiar...... :rolleyes:

[Alectrician]

The manufacturers of wire nuts simply tried to distance themselves from the whole aluminum wire thing so at some point they declared their products were for copper wire only. They didn't change the materials in their product their lawyers just told them to say "no al wire".

You guys get all worked up over nothing. When properly installed (properly stripped wire w/ no ringing and tight connections) wire nuts are work just fine.

[jwelectric]

Man, you just keep digging. Isn't six feet deep enough? :rolleyes:You guys get all worked up over nothing. When properly installed (properly stripped wire w/ no ringing and tight connections) wire nuts are work just fine.

My first electrical job was in the summer of 1968. I had just turned 17 and got my drivers license. I was ready to take on the world. This first house was one of my fondest memories in the electrical trade as I got to do all the drilling.

http://www.kensalrental.com/Brace_and_Bit_pic.jpg.

This old house was way up a holler in the foothills between the Blue Ridge and Smokey Mountains just inside Wilkes County NC. I remember one chilly morning the old man left the truck door open. It was a 1949 Ford with a top roller four speed transmission and a flat head in-line eight cylinder engine. The sun had been up for about an hour when the old man said he was going down the hill to get us something for breakfast. About 100 yards down the side of the hill the old man jumped out that truck with a groundhog climbing over the top of his shoulder. Guess the critter crawled up under the seat cause it was warmer in there than outside.
When the old man came back he had a fatback biscuit and a big cup of coffee and he always took out $.25 from my pay to pay for it.

Code books back in that day were hard to find and electricians with enough education to read them was even harder to find. I was lucky in so much as the old man I worked for could count money pretty good and never shorted me a minute on my pay. Although he was paying me $1.65 per hour it never bothered him one bit to explain to me how to make up a joint whether it was a telegraph joint in Knob and Tube or taping a crimp connector on NM cable.

Another memory I have is of the wire connectors we used back in the day. We had split bolts just as you see them today but most of the joints that were made in boxes were a crimp and tape. What do most of you see in older houses especially those with aluminum wiring? When we crimped a copper and aluminum together we used a special crimp that kept the two wires from touching just like the ones today except the ones today don’t take as much power to squeeze.

Sometime when I have a little longer I will tell you all about the two deer the old man shot from the back porch of that old house on the side of the mountain. Shot the buck in the back of the head and the bullet went through his neck and killed the doe he had mounted.
Didn't eat no fatback for over a week and the coffee was only a dime. Saved myself 75 cents that week.

[jwelectric]

Don't you have a service call or something to do?;)

No I don’t so let me tell you about my first raise. When I went to work for this old man up there in them mountains minimum wage was $1.15 and he was paying me fifty cent above that.
We averaged working about 9 hours a day that first winter and as spring was working itself in the old man came to me and ask if I would work for a days price instead of by the hour. I was making about $14.85 a day and was proud of my high pay rate.

Well this old man was going to offer me Twenty Dollars a day. My Pops wasn’t brining home but just over $40.00 a week at the cotton mill. This offer of $20.00 a day was more than I could stand. I was so excited about making $100.00 a week I was about to burst.

Long about the middle of summer on a warm Sunday afternoon me and Pops was sitting on the river bank trying to catch a big old cat fish for supper when he pointed out that I was leaving home before the sun came up and it was dark when I got home. Well around this time of year the sun comes up around 5:30AM and goes down around 9:30PM. This with a lunch break equals about 14 hours a day.

Now let’s all take a look at my raise. 14 hours a day divided by twenty dollars a day equals just over $1.42 per hour. Yes I did have a talk with the old man.
Know what he told me? He said, “Sit up and take notice cause some day you will be running a crew just like this one.”
Well I looked around and all I could see was one old man and myself. Maybe someday I will be running a big crew like that myself.

[Verdeboy]

Nice stories, JW.

Keep 'em coming.

[Alectrician]

From Ideal in response to my query. I was quite impressed that they took the time to contact me.



""Underwriters Laboratories revised the applicable standard -- UL 486C --
effective Jan. 1, 1986.""

I wonder what we were suppose to do between 1968 and 1986???



""You are correct that prior to that date, virtually
all twist-on connectors could be, and indeed most were, listed for
copper-to-copper, copper-to-aluminum, and aluminum-to-aluminum
combinations.

With the 1986 revision, a heat-rise addition was made to the
standard that effectively prevented all twist-on connectors from meeting
the new requirements.""



" Because aluminum wiring, unless otherwise prevented
from oxidizing, will naturally oxidize over time and result in a layer of
semi-conducting aluminum oxide forming when in intimate contact with a
reducing material -- such as copper. This layer of aluminum oxide causes
the resulting connection to heat up to the point that the connection will
exceed to the UL heat-rise requirement. ""

I call BS.



"" This addition to the standard was
made because of the problems experienced in real world applications with
standard compression connectors (of which twist-on's are one type)
involving copper-to-aluminum connections.""


Again...BS. I am IN the real world have seen a LOT of AL and al/cu splices and have NEVER seen a failure due to oxidation unless there was water dripping on it or it was underground. A regular splice in a jbox....NEVER.



"In 1995, IDEAL INDUSTRIES, INC. introduced the Twister Al/Cu wire
connector, which was and remains the only UL-listed and CSA-recognized
twist-on connector that meets the revised requirements of UL 486C."

What were we supposed to do between 1986 and 1995??



"The connector contains a proprietary antioxidant filled in such a manner that
no air remains inside the connector end to cause oxidation subsequent to
installation.

One of the reasons that simply adding an antioxidant to a
conventional twist-on connector, such as an IDEAL Wing-Nut connector, will
not meet the revised UL 486C requirements is that it is very difficult to
field-install an antioxidant to exclude a pocket of air from forming at the
end of the connector. Only a very small amount of entrapped air is needed
for oxidation to occur, and the connection to potentially overheat."

*****It is very difficult to field-install an antioxidant to exclude a pocket of air from forming at the end of the connector.????*****

Come on now. It is very difficult to install 4" underground conduit, transition it into the proper alignment for the panel, pull the feeders in, install all the branch circuitry, trim it all out and chase down your money. It is NOT difficult to put some anti oxident into a wirenut.


"We hope this addresses your inquiry adequately. Please feel free to
contact me directly if you would like further information."

It did answer a lot of my questions and I thank them VERY much for taking the time to respond. I do still think that thier "special" wire nuts are not special at all. Real oxidation...the kind which would affect conductivity, will not occur in a normal setting.

[jadnashua]

Are you familiar with a thermite reaction? Basically, powdered aluminum and powdered iron oxide (rusted iron). If you get the reaction started, the aluminum will strip the oxygen out of the rust, leave molten iron, and end up as aluminum dioxide (aluminum rust) and iron after it cools off. Aluminum in its elemental state almost always has or will have within milliseconds a rust layer on top. The reason it doesn't flake away like iron is that it is both very stable and essentially the same size as elemental aluminum thus sealing the surface as opposed to iron oxide which is bigger in volume, thus exposing more elemental iron to the ravages of the oxygen rich environment we live in.

You've been lucky...aluminum will rust without any moisture or other accelerants all on its own. Aluminum oxide is an insulator, thus acts like a resistor, thus generates heat. That's dangerous.

[jwelectric]

I am TRYING to open up a dialog

Okay then how about explaing the plain old chemical facts found in this link (http://www.dossert.com/technicalinfo/corrosion.htm)

Being that the chemical reaction has not changed over the past few thousand years I wonder just what you base your statements on.

Let me also say that I can sit here as type anything I want to and say it is what someone else said but instead I would rather give a link to a site that everyone can research theirself.

[jwelectric]

I just want to know what you did between 86 and 95 to make splices in Al wiring? Splicing what to what?
I used a component that was listed for the use as was outlined in the NEC that I copied and posted.

I can show you aluminum terminations that are bad and good, inside and outside, aluminum to aluminum, and various other installations.
What I can’t do, nor can you, is show a connection of copper to aluminum where the copper comes in contact with aluminum that is more than a couple of years old that is a good connection.
Up till this point the discussion has been about the splicing copper to aluminum at which you came back with some cock and bull that was supposedly from some manufacture of wire nuts that wouldn’t hold water on the best of days.

Now that I have posted a link that explains the chemical reaction when aluminum comes in contact with copper no matter where it is located I await your reaction.
I patiently await your explanation of how you can stop galvanic corrosion of the two metals when current is passed through them.

Antioxidants will stop the oxidation of the aluminum but it will not stop the galvanic corrosion that is an electro-chemical reaction between the two metals.
Please send that wire nut manufacture an email and have them explain this away.

[jadnashua]

The point trying to be made is that while people think of aluminum as being very stable, it has a very high afinity to react with other metals and oxygen. The thing that saves it from wasting away to a lump of AlO2 is that it generates a coating that insulates the interior portion of the metal from oxygen. I tried to point out how much Al wants to corrode by the thermite example...it will literally strip the oxygen from the FeO2 molecule, and as it becomes more stable, gives off a huge amount of heat, enough to leave liquid iron as the result.

Stick aluminum in intimate contact with other metals, and it WILL end up with corrosion. How much is determined by how far apart they are in their reactivity. Stick copper and iron together, and you've got problems. Stick copper and brass (an alloy) together and you're okay. Aluminum is quite reactive. It also expands and contracts much more than some other metals, and this action as well can make electrical connections fail - the reaction can expose more elemental aluminum to corrosion, and work screws out, when used.

[jadnashua]

Different metals in contact with each other produce galvanic action...i.e., produce a battery effect. When that happens, one accepts electrons and the other gives them off. In the process, the metals are changed. Same thing happens in your car battery. If you select metals to touch that are very similar, you get almost no reaction, or it is so slow that you would be hard pressed to notice in your lifetime (but it does and is measurable). It just so happens that aluminum is near one end of this scale which means that most other metals will react with it. It doesn't require air, but if you can cut that out, it does slow things down some, but cannot stop it. Choose metals far apart on the scale, and you get major corrosion fairly quickly.

There's all sorts of info on this, here's one link I googled http://www.wpbschoolhouse.btinternet.co.uk/page03/Reactivity.htm#aluminium

[jimbo]

This thread has gone off the track a little, so in the interest of civility I closed the thread. If anyone wishes to continue a discussion of the corrosion or whatever in a quieter tone, please start a new thread.