Copper vs Aluminum Wire

[Boyntonstu]

I was working as an Electronics Reliability Engineer, and one night my neighbors house was in flames.
The next day, I was asked to investigate the cause.

Potomac Electric Power Company used a #2 Aluminum wire between the outside meter and the breaker box in his basement. I determined that the fire started with the wire overheating causing flammables to ignite.

Aluminum cold flows, has an insulating oxide, and carries much less current than copper of the same diameter.
The Code calls for a 2/0 copper wire for 200 Amps and the #2 Al that PEPCO installed was way undersized.
It turned out that exterior wire up to the meter and the wiring inside the homes are covered by Codes, but the 8 foot service connection wire was not covered.

The situation escalated and we had 275 houses inspected by an electrician and a representative of PEPCO.
We discovered several hot breaker boxes!
We then had a TV debate between a PEPCO engineer and myself about how and when the #2 wire could pass 200 Amps. I easily won the debate.
The story was covered in a 2 column story in the Washington Post, and I was thereafter called Mr. Aluminum Wire.
Several concerned homeowner associations invited me to speak about Aluminum wire.

Finally, PEPCO came to our Cheviot Hills development, and exchanged a 2/0 Copper wire for the #2 Aluminum in all 275 houses.

Aluminum wire was quite a big deal back then.

[Art]

My old Road ranger TT was wired with aluminum from the factory
I was not amused when the wire melted and ruined my electrical, but at least I didn't burn

[Blacktank]

i'm just not a fan of aluminium,give it a good stink eye and it will stress fracture not to mention what happens when you put a steel bolt in the stuff so i like to avoid the stuff if possible

[Putts]

As a scanning electron microscope technician in a previous lifetime, I can tell you i've looked at a lot of aluminum. Not because it's some lovely substance---thogh it is---but because  it's so convenient and efficient while being a pain in the ass at the same time. 

Vapor deposited aluminum substrates on silicon electronics chips grow whiskers where the gold connection wires are thermo-mechanically bonded from pin to aluminum substrate traces on the chip if it's humid enough.

Aluminum is ductile and granular at the same time, making it superb for extruded shapes, yet prone to catastrophic fracture unexpectedly propagated from grain boundary failure.

Going beyond my real knowledge base here, this granular nature gets in the way of of the smooth strength of other eutectic alloys, creating hot spots at high resistance points of random grain boundaries to electrical current flow.

I have a saying, "I've never met a human that wasn't incredibly beautiful and fatally flawed."

I reckon aluminum is the most human of metals.





(Please realize I'm hammered at a bar in the Hyatt Denver Tech Center, and know i have to work like a dog tomorrow. 
IMHO, aluminum wires would be shit for a van. Too prone to troubles with constant vibration. Stick to marine stranded copper.)

[Scott7022]

What a beautiful and eloquent bit of prose on aluminium. I like it!

But I would use it for anything but a heatsink, and never to carry current. Didn't like having 4500 psi strapped on my back either.

[Boyntonstu]

As a scanning electron microscope technician in a previous lifetime, I can tell you i've looked at a lot of aluminum. Not because it's some lovely substance---thogh it is---but because  it's so convenient and efficient while being a pain in the ass at the same time. 

Vapor deposited aluminum substrates on silicon electronics chips grow whiskers where the gold connection wires are thermo-mechanically bonded from pin to aluminum substrate traces on the chip if it's humid enough.

Aluminum is ductile and granular at the same time, making it superb for extruded shapes, yet prone to catastrophic fracture unexpectedly propagated from grain boundary failure.

Going beyond my real knowledge base here, this granular nature gets in the way of of the smooth strength of other eutectic alloys, creating hot spots at high resistance points of random grain boundaries to electrical current flow.

I have a saying, "I've never met a human that wasn't incredibly beautiful and fatally flawed."

I reckon aluminum is the most human of metals.





(Please realize I'm hammered at a bar in the Hyatt Denver Tech Center, and know i have to work like a dog tomorrow. 
IMHO, aluminum wires would be shit for a van. Too prone to troubles with constant vibration. Stick to marine stranded copper.)

Mr. Purple Plague?