Hey electricians...

[M_Six]

...I suggested to a person I know that they try using the electrical system networking gear for their home. They told me it probably won't work because they have aluminum wiring instead of copper. Is that possible? I don't think I've ever seen aluminum wiring.

TIA

[vass0922]

Don't know about the wiring thing, but HomePNA networking (using phone wires) may also be a consideration.

[crystaldragon]

They are probably right.

Aluminum electrical wiring has a higher resistance than copper which would be a problem with data signals because there isn't enough current involved to overcome it

[John Prophet]

surely there would be a blurb about it on one of the websites

[whitebeard21]

Aluminum wiring does not meet the nec. If you have it in your house either replace it or buy lots of fire insurance. I don't think you can even sell a house with aluminum wiring. Might just be a local ordinance instead of national.

If the house is old enough to have aluminum wiring it probably has cat 1 phone wires which is no good either, the best alternative is wireless

[sao95]

aluminum wiring going from the meter to the fuse box is still allowed

[Prexaspes]

Aluminum's resistance isn't really much higher than copper's. Probably talking about milli-ohms per foot of wire. It won't really drop much more voltage than copper; with such low levels of resistance difference current won't be affected very much. I haven't really looked into electrical system networking, but I imagine it's probably just a high frequency signal sent over to the reciever/amplifier. After passing through some trans-amps and resonant circuits, the signal is amplified and filtered out from all the background noise. If there is a problem with resistance, it would probably just cause a higher error rate and slower networking due to signal attenuation from the amplitude reduction of the signal over the line.

But the issue he should be adressing is the aluminum wiring in his house. It has been known to cause fires.

[Knothead]

This is wild! First time I've ever heard of aluminum wiring! I have only ever seen solid and threaded copper....huh!

[no1_vern]

Aluminum wiring may not pass your local wiring codes. The problem of thermal expansion and contraction tends to loosen connections at screw terminals. This creates high resistance connections which can over-heat and/or cause sparking. Both are serious fire hazards. Check with a qualified electrical contractor or building inspector.

From Steve of "This Old House"
Steve says : I'd suggest calling a competent electrician to give you a bid on both making the existing system safer or rewiring altogether. Aluminum wiring can lead to loose connections, excessive overheating and fire-and the possibility of an electrical fire is something to avoid at all costs.

And the NEC says: http://www.homewiringandmore.com/aluminum/index.html

One of the main reasons that Aluminum is used instead of copper is that it is a lot cheaper than copper. Sometimes Copper was 4 times as expensive as Aluminum.

Edit Also ". Aluminum wiring is still permitted and used for certain applications, including residential service entrance wiring and single-purpose higher amperage circuits such as 240V air conditioning or electric range circuits. "

From http://www.inspect-ny.com/aluminum.htm

[Prexaspes]

Aluminum used to be used in house wiring in the 70's. The big problem with aluminum is that it oxidizes and it's oxidation is sped up when it comes in contact with other metals. Like the stuff you'd commonly connect to your wiring system. This oxidation increases resistance in that section of wiring, causing it to heat up, and possible start fires.

The best thing to do with it short of rewiring is to pigtail it wherever you need to use it and make sure you coat it with antioxidant grease. They make special Al/Cu connectors for this purpose.