Does anyone know if aluminum wire is appropriate for outdoor landscape low voltage lighting? Copper is getting a bit expensive so I thought in an outdoor, low voltage situation, aluminum might be a better way to go.

AL wire is totally and absolutely useless for anything.

LearJet

That is just your opinion.

I certainly would not use Al wiring outdoors/underground.

For other applications, Al could be a cost effective way to install feeders. There are many ways to accomplish this, raceways, MC, etc...

If all of your runs were in PVC, and all your connections in above grade "power posts", with DB rated connectors, aluminum would be great.

For the typical LV, direct burial setup, I'd have a hard time trusitng it. Too bad, since LV lighting uses some heavy cable, the copper adds up.

I agree with PCBelarge and mhulbert.

Unless the manufacturer of the power unit for the system specifically allows a differant cable type or conductor type in their installation instructions, aluminum would not be permitted IMO.

In UL's White Book, under the heading of Landscape Lighting Systems, Low Voltage (IFDH), the conductors should be listed SPT-3 or SPT-2-W.

Under the heading of Flexible Cord (zjcz) in the first paragraph " All conductors are stranded copper."

Learjet has expressed the feeling of "the trade" ... if not that of the wire manufacturers!

Aluminum, anywhere near the ground, can't help but have corrosion issues. Nor have I ever seen a landscape lighting transformer listed for use with aluminum wire. As far as I know, aluminum is not currently made in wire finer than #6. (I could be wrong on that).

Indeed, the only place I see aluminum used is in the PoCo service drops.

But, before I get my shorts in a know over "can I or can't I," I'd look to see if the stuff exists first of all.

No he has not spoken for "the trade".

Aluminum can be and is used without problem for many circuits.

Would I use it for direct burial?

Would I recommend it for a seaside installation?

No.

Inside a building for feeders yes it is a fine product.

Around here aluminum cable is used on 99.9% of residential services. The standard here is 4/0 Al. SEU service cable.
I have even seen some commercial feeders being run in aluminum .

Most European power companies have been known to run Al underground feeders everywhere, so it must be possible. One thing though: they always use crimp splices and embed them in some kind of resin, so there is absolutely NO chance of moisture or air getting to the connections.

Nothing wrong with aluminum, just as long as you have your Noalox handy.

I think this thread is getting way off-topic

the use of AL for large-size feeders has been debated many times on this forum. We don't need to get into it here.

for the underground LV stuff I think it would not work at all, considering the connectors usually tap the insulation of the wire, and AL turns to white powder real qick with even a small hole in it I don't think an installation in this manner would survive more than a couple weeks

just MHO
-Will

Wow, I am surprised at all of the bad vibes about using aluminum. Our POCOs here use 100% aluminum, all the way down to #6 for street lights.

The key in using aluminum is installing it properly. If the backfill is clean and the splices/terminations are done correctly, it works. That's just it......Getting it installed correctly.

No direct burial cable is safe from dig-ups. Most failures result from nicks (planting a bush for example). The cable gets a nick from a shovel but nobody says anything and just tapes it (if anything) and buries it. Even copper DB will fail if nicked.

I get the impression that you are looking at some long runs or you wouldn't have asked the question. You can't get aluminum any smaller than #6 anyway, but I would imagine that you'd need that size or more. You certainly can't use the standard tap connectors usually used in LV lighting. You would need to use dual-rated terminals, preferrably Hypress type that provide a copper-equivalent termination. By the time you invest in the terminals and the tooling, you might not be saving any money by using aluminum.

On a good note, aluminum wire fails much more quickly when it has been damaged than copper when direct-buried. Usually, troubleshooting to locate the fault is pretty simple. I did my time servicing an apartment complex that used 100% aluminum that had been nicked and damaged since the day it was installed. I must say that it's predictable.

[This message has been edited by EV607797 (edited 12-18-2006).]

[This message has been edited by EV607797 (edited 12-18-2006).]