Use of Copper Clad Aluminum Wire

cjack posted:

Common guys, it's not a religion. Copper clad aluminum is perfectly good wire. You just have to research the specifications, cost, and understand how it fits your layout. Think about it...the engines and cars get their power thru steel rails. Talk about resistance! And understanding that, you just have to use more drops. Same with copper clad aluminum as wire.

The first reasonable response to this thread.  Nearly all the negative responses to aluminum wiring come from a general lack of knowledge about the use of the material. 

Branch circuit (15 amp / 14 gauge and 20 amp / 12 gauge) solid and stranded aluminum conductors became popular starting in the 60's and lasted into the 70's.  The main issues with these conductors for standard line voltage home wiring were two-fold.

1. A lack of skill and/or knowledge on the part of the installer.  Aluminum is more malleable than copper.  If the installer over-tightened a screw or a wire nut, the wire was more prone to being flattened creating more resistance that in some instances resulted in fire. 
2. In subsequent remodels, copper was mixed freely with aluminum and the dissimilar metals degraded over time.  This has largely been addressed in most building codes including the NEC and IEC requiring special wire nuts and a conductive paste to separate the metals in residential remodel uses.  It is not permitted in new construction until you get into the larger conductors that are not part of the branch circuits.  Some municipalities have gone further and require special connectors that physically separate the copper and aluminum conductors in existing construction.

Consider that many homes from this period still have the original wiring and have not had issues.  Aluminum is still the material of choice for larger conductors in the #4 and larger sized typically and used exclusively in high power installations.  The code does not regulate low voltage wiring at less than 24V, because at that voltage it does not create a life safety hazard at the amperage low voltage circuits operate at.

To fear the material for use on a layout is illogical based on purely information and anecdotal evidence from line voltage circuitry. 

Now to the OP, Cjacks response is one of several correct ones.  It's a value proposition. Is the savings really there or not?  That is a question that can only be answered by testing the two materials. 

I suspect that at the end of the day there isn't a lot of difference in total cost due to the size of most home layouts but that is merely speculation on my part.

With the amount of money that we spend on trains the difference in cost between copper and aluminum is minimal. Spend the money on the stranded copper.

Mikey

Wow. Lotta' misplaced passion here.

I use 12 bore COPPER CLAD aluminum wire as my power buss and you know what? It works just fine. It's big wire carrying a small current. I also use plain old wire nuts for connections to drops. BTW, the house hasn't even burned down yet. 

The problem is deterioration of the interconnects over time. They become a problem, especially with vibration. Look at all the noise (vibration) that the engines make going around the layout.

Suitcase connectors have the same problems. Deterioration with time and vibration.

George Tannery

CCA wire may be fine if you mechanically connect it, but from experience it is difficult to solder especially in the larger sizes.  My main feeds are 1/0 and are almost impossible to solder with CCA.  I might be getting my hobbies mixed up here, I dabble in Car Audio also.

Chris S.

ALCo used aluminum (non-clad) wiring harnesses on the last of their locomotives.  Some of it just turned to powder after 30+ years.  So, if its permanence you want, use copper.

The main reason aluminum wire is not used in homes much anymore is due to a condition known as “cold flow”.

  Cold flow in aluminum terminations causes the mechanical splice to physically loose its “tightness” by absorbing the initial compression or torque force applied to the joint by the Electrician during install.

   The splice will usually begin to heat up, faster, depending on the branch circuit load, due to the increased resistance (arcing)of the faulty connection .

This just becomes worse and more hazardous over time until there is an open circuit condition or fire

    This means that terminations performed without using the correct UL/CSA approved connectors and procedures, will loosen from the initial torque/force used by the Installer, be it under a terminal screw or a mechanical splice point.

   Unlike copper wiring,  older homes with aluminum wiring require periodic inspection/re-tightening of all panel connections ,receptacles and splice points within a home by a Certified Electrician to ensure no loose or “hot” connections are allowed to develop.

  As mentioned previously, proper approved accessories and procedures were developed to alleviate this issue and are now enforced thru local and national electrical code organizations

Al

Both my AC wiring and the wire from the pole /transformer to the house was AL. I removed all of the AL wiring, I also got the Power co (PSEG_LI) to replace the two legs to the house with 2 AWG Copper and had them replace the Steel Neutral support cable  with a Copper alloy 1/2"  one.  Al is not a metal it is a metaloid which means it has some of the properties of both a metal and a non metal,  it heats up and becomes brittle under load. I also had them replace the transformer since there was a fire  in it and the pole because the termites had eaten the heart of the pole and in a wind I could see the  700lb transformer on the pole sway.  The high voltage cable to the transformer 4400 VAC is AL, During  Sandy it could not stand the wind and snapped and set fire to the tree it hit.  AL wire no way!!!!