Compact Aluminum wire for new shop. Any good?

We are all aware and have read of the problems with aluminum wire. So, we are building a new shop, one of the electrical bidders come in and I ask if he is using copper. "No, we use compact aluminum". No, I say, I want copper; aluminum is too much hassle for me. He replies with reassurance that this is not the aluminum of the past. He's been installing this for years without issues....blah, blah, blah. I've never actually heard aluminum wire called "compact" before. Is this actually an improved product or still the same turd with a different colored bow?

First issue is it's your building. If he doesn't want to do copper, then find another contractor. I agree with using copper.

There have been advances in aluminum wire since the 60's and 70's. The power companies routinely use aluminum, but then that know how to use it. Lets say that you do go with aluminum. In a few years the system needs work for whatever reason. Will the new electrician know how to handle the stuff? Copper is probably more expensive but is it worth the risk?

Tom

edit:- Do a Google search using "nec code aluminum wire" or other search term. Compacting means the space between the strands as be eliminated meaning that the wire acts like a solid conductor, not stranded. Further, alloy additions have reduced the cold flow of old al wire. You are still restricted on terminating the wire as in twist on connectors cannot be used to join al to cu wire. Some connectors require anti-oxidation compounds, others don't.

Your choice.

Tom

Tagged, subscribed, and watching because we're in the same boat...

I am sure your contractor meant that he uses compact aluminum wire for the "big stuff" - feeders to panels, large machines (over 60A) and the like.

In these cases, aluminum wire can be terminated easily. Most all lugs are dual rated - copper/aluminum, just clean, apply No-Lox, and torque to spec.

Aluminum should NOT be used for branch wiring - outlets, switches, lights, etc.

Just my humble opinion.

Steve

grounded-b said:

I am sure your contractor meant that he uses compact aluminum wire for the "big stuff" - feeders to panels, large machines (over 60A) and the like.
In these cases, aluminum wire can be terminated easily. Most all lugs are dual rated - copper/aluminum, just clean, apply No-Lox, and torque to spec.
Aluminum should NOT be used for branch wiring - outlets, switches, lights, etc.
Just my humble opinion.
Steve

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So, as this is your first post, welcome to the forum. Hopefully this does not derail FK's thread at all, but in the hopes that it is relevant ( to both he and I ) - Where in Wisconsin are you and what do you do for a living?

grounded-b said:

I am sure your contractor meant that he uses compact aluminum wire for the "big stuff" - feeders to panels, large machines (over 60A) and the like.

In these cases, aluminum wire can be terminated easily. Most all lugs are dual rated - copper/aluminum, just clean, apply No-Lox, and torque to spec.

Aluminum should NOT be used for branch wiring - outlets, switches, lights, etc.

Just my humble opinion.

Steve

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That is pretty much the impression I got from him as well. And to be clear, this is not a "bash" on this guy. He actually seems very intelligent, honest and straight forward. Doesn't seem to be "selling" me on an inferior product. He is willing to put in copper, just said that this aluminum works and obviously is cheaper. I've just never heard of "compact aluminum" before. Was it always called that and we just refer to it as aluminum wire? Or is it something new/improved to handle the issues of old.

Here is an example of a compact conductor.

Is this actually an improved product or still the same turd with a different colored bow?

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Were not in the 60's any longer, and neither is the aluminum alloy used for conductors. Many of the bad experiences were from internal house wiring, and installations where the equipment terminations were not designed to allow for aluminum conductors. There was a problem with thermal expansion and corrosion in the early products. It still has a greater coefficient of expansion, under load than copper, but not near as bad as it used to be.

Earlier products needed to be wire brushed to remove oxides immediately before termination, and then coated with anti oxidant compound to prevent future oxidation. This is no longer required, but is still a good practice, especially where terminated outdoors.

Most distribution equipment lugs today are made of the same material and are approved for either type metal. With termination lugs of the same material, the temperature expansion is less of an issue as they expand at a similar rate.

This conductor is used for services and large feeders almost exclusively today, especially on large and long runs, to reduce cost. However it needs to be up sized from an equivalent copper conductor, which means that the conduit needs to up sized as well.

It isn't even offered in individual conductors in small sizes generally, as would be used in branch circuits for equipment and general loads. The exception is in home cables such as for a range, A/C or dryer circuits.

The most cost savings can be had with underground use, with PVC conduit, as compared to rigid steel conduit and copper conductors. If the circuits are oversized, from the bare minimum requirements, that reduces most of the expansion from running under loaded conditions.

Even many distribution transformers are wound with aluminum wire today, and terminated in aluminum lugs.

The long term reliability of aluminum is really dependent on the selection of material, insulation type and installer skill. It can be used effectively to reduce cost, dependent on conditions. It is widely used, and stable when done properly.

Copper is still the premium material. Conducts away heat better. Less corrosion effects, and the corrosion is still conductive. Best used for heavy demanding loads and all internal building small feeders and branch circuits. But comes at a premium price.

Any competent electrical contractor should have no problem pricing a job with either material, where it is appropriate for use.

SAF Ω

SAF Less corrosion effects said:

corrosion is still conductive[/B].

SAF Ω

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Copper oxide is a semiconductor. Remember copper oxide rectifiers?

NEMA had a 8 hour temperature test in the 1930's or so to make sure that the copper switch contacts didn't go into thermo runaway because of copper oxide creeping in between the contacts.

Tom

Copper oxide rectifiers were a bit before my time, I worked with a few selenium ones though.

So can you tell us what the results of the NEMA temperature test were, Did the contacts pass the test?

SAF Ω

Zahnrad Kopf said:

So, as this is your first post, welcome to the forum. Hopefully this does not derail FK's thread at all, but in the hopes that it is relevant ( to both he and I ) - Where in Wisconsin are you and what do you do for a living?

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Industrial electrician living in Milwaukee, WI

Found this forum because I have to repair a 1960's Monarch 10EE lathe. With the vacuum tube motor controller

grounded-b said:

Industrial electrician living in Milwaukee, WI

Found this forum because I have to repair a 1960's Monarch 10EE lathe. With the vacuum tube motor controller

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Shoot me your information if you are open to it. We are in the process of looking for a building or the land to build one upon. Once that happens, electrical won't be far behind and I refuse to do it the hard way again. I can be reached through the forum via email or private message, as well as the contact page from our website. ( American Machine & Gear Works ) Thanks.

TDegenhart said:

Lets say that you do go with aluminum. In a few years the system needs work for whatever reason. Will the new electrician know how to handle the stuff?

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"in a few years" any sparks as does not ALREADY have the knowledge will have to have acquired it.

Copper is waaay more expensive, "relatively" than it once was, and we are not going to be seeing much of it for feeders within a commercial building in future any more than we have seen it very much on the feeds TO buildings and residences for rather a long time now since the first major changes to what HAD been an all-around problematic alloy, and is no longer much of a negative atall.

I still do not LIKE Aluminium, personally.

But WTF? Other fish to electrocute.

I can't be bothered trying to boil that particular part of the ocean.

I suspect that in the same boat, my idea of "premium quality" might be to pay for a one-size upgrade to Al distribution conductors rather than to insist on Cu at far higher premium cost.

A failed or failing termination INSIDE an industrial load center is seldom a disaster, nor even close, anyway. Part of why they even exist is a "containment" function.

It was back when Harry Homeblower had it inside walls and such and knew not, that it was setting homes afire.

Primary service entrance load centers, utility company side, especially, didn't have huge issues even back when the Alloy had nasty creep. Higher maintenance costs, yes. Hollywood-level drama, with fire bombs and car chases? Much less-so.

2 ..... aluminium East German coins worth,

FK said:

He replies with reassurance that this is not the aluminum of the past. He's been installing this for years without issues....blah, blah, blah.

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Ask for references. Ask what they think.

The power company out here uses stranded aluminium for the main power ground. The only issue I have is when the squirrels chew on it to sharpen their teeth. Chewed it in half. The power company guy said if it was up to him he would issue a few thousand air rifles to customers, to cut down his work load.

I personally don't like Aluminum for machine drops where there is any kind of vibration.
Most machine connections will require lugs rated for Aluminium, most are not.
The same goes for older breakers and buss duct plugs.
So copper is a natural in these cases.

Bill

hitandmiss said:

I personally don't like Aluminum for machine drops where there is any kind of vibration.
Most machine connections will require lugs rated for Aluminium, most are not.
The same goes for older breakers and buss duct plugs.
So copper is a natural in these cases.

Bill

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Actually a great deal of new manufacture IS "AL-CU" rated and so marked. Likewise your sparks travels with Al-Cu splice and lug hardware in the truck. It is even on the wall at most Big Box.

That said, I do NOT want Al leaving the entrance / main distribution load centers.

Breakers and beyond? The runs are shorter, the switchgear, conduit, hangars or other support anchorage, bonding & grounding, and labor cost is significant, regardless, and the premium for copper just one cost element among many.

That makes the last few yards of it more affordable "relatively" in the overall costing of the whole job, so there isn't much to justify declining savings.

Just use Copper. It is indeed a "natural". Then go resolve some more pressing issue that is less-so.

2 COPPER CW

About that 10EE, you have no doubt found the section here on Monarch.... Should be lots of help there. I was even at one time working on a solid state tube replacement for those, but the demand seemed low.

Aluminum wires? It could be worse... How about sodium electrical cables?

Evaluation of Sodium Conductor Power Cable

JST said:

About that 10EE, you have no doubt found the section here on Monarch.... Should be lots of help there. I was even at one time working on a solid state tube replacement for those, but the demand seemed low.

Aluminum wires? It could be worse... How about sodium electrical cables?

Evaluation of Sodium Conductor Power Cable

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Just don't get the conductors wet or have any nicks that would expose the sodium to moisture. All terminations would have to be in oil.

Tom

JST said:

Aluminum wires? It could be worse... How about sodium electrical cables?

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Not so fast, McGee!

Superconductors have been in use for a while now, out Asia way, where population densities are borderline insane (or maybe well-beyond just "borderline" ?) and space for transmission facilities is worth Gold, not Copper. Major producers, of course, include Japan ..and China.

"http://www.furukawaelectric.com/fehk/en/product/energy/power_cable/sc.html"

"https://asian-power.com/project/news/shanghai-electric-cable-expands-alliance-amsc"

Advances have kept coming.

Note the stats in this old article as to how much our (heavily Aluminized?) grid wastes in the USA. Not bad as a percentage. Not bad atall if you've ever had to distribute over the distances we have vs Europe.

Still.,, staggering in MW:

World's first superconducting power line paves the way for billions of dollars in savings, more nuclear power stations - ExtremeTech

TDegenhart said:

Just don't get the conductors wet or have any nicks that would expose the sodium to moisture. All terminations would have to be in oil.

Tom

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Surprisingly, the data I saw did not support extreme measures. Insulation was polyethylene, and connections were not an issue. Holes in the insulation were actually found to get sealed off by corrosion products.

Biggest issue was apparently the near zero tensile strength of the material.

There were some underground cables put in and used for some time, apparently. I notice that they are not STILL used, however.

It made some sense, as there s a lot of sodium available.

JST said:

It made some sense, as there s a lot of sodium available.

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True enough. But there is twice as much iron, three times as much Aluminium, and ten times as much silicon in the lithosphere - all of them easier to handle with little or no special care - as well.