I have seen volume produced cheap motors and transformers wound with Alu
wire, it resembled the usual copper "magnet wire" but once I scratched
off the insulating Enamel layer, I could not solder it and it was white,
not the copper-yellow color and stiffer than I expected, so then I
realized it was Alu.
At my home, the electric supply is coming into my service panel using
Alu wires, but all house wiring is copper. I still need to re-do the
attachment of the Alu wire into the service panel as the insulation on
one wire is discolored right next to the attachment point, so apparently
it does not make good contact and will fail when we draw high currents.
Luckily I have disabled both Airco and electric dryer, the two top power
users, so before that I re-dedicate one (or both) of them for Electrical
Vehicle fast charging, I will redo the wire and make sure it is clean,
gooped and tight.

Seeing this wire in the service panel tells me that probably all of the
underground wiring in our park is Alu (there are several concrete
pad-mounted transformers spread around the park, each receiving power
and feeding some 100 homes at a time via underground wiring)

Also the high voltage overhead power lines in the distribution network
between substations uses Alu for the wires, often wound around a steel
core for strength. I hear the overhead wires wiggle and making sound in
a nearby line, but PG&E confirms that this is of no concern - even
though the movement is occasionally so strong that it vibrates the
towers. Note that this is not wind-movement. I suspect that purely the
magnetic field of the lines causes them to vibrate at a resonant
frequency because I hear it on wind still days. That is also a reason
that cables are stranded: to resist the flexing due to movement of the
cable.

Another place where I have seen solid alu wire with a thin copper
coating is in Coax cables, where the high frequent energy is only
penetrating the "skin" of the conductor anyways, so even if the core was
made from plastic with a copper coating, it would be electrically
equivalent. Though it also has mechanical properties, so that is why it
is made from Alu instead.
The shielding outside layer of a coax cable typically has an alu foil
and thin copper wires woven cross-wise.

Cor van de Water 
Chief Scientist 
Proxim Wireless 
  
office +1 408 383 7626                    Skype: cor_van_de_water 
XoIP   +31 87 784 1130                    private: cvandewater.info 

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-----Original Message-----
From: EV [mailto:[email protected]] On Behalf Of EVDL
Administrator via EV
Sent: Thursday, April 14, 2016 1:58 PM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] Aluminum: EVLN: Miners pin hopes on Electric
copper-cars

On 14 Apr 2016 at 13:15, brucedp5 via EV wrote:

> So is aluminum that such a good idea for power line/wiring use of any
kind?

Aluminum wire has been used for larger (stranded) power cables for many 
decades, and it's given good service.  You do have to size it larger
because 
of its higher resistance, and use Noalox or other goop on the
connections to 
prevent oxidation from raising the resistance at the connection.

For a while, IIRC something over 4 decades ago, solid AL building wire
in 
#12 and #14 was used in place of #14 and #14 for residential branch 
circuits.  It proved to be unreliable and hazardous.  I think that was 
because the solid (vs stranded) wire deformed too much under receptacle
and 
switch terminal screws.  With thermal cycling the connections loosened, 
developed oxidation, and heated up.  There were some home fires as a
result. 
 But AL is fine in larger sizes and in stranded type.

I don't think I'd use it for an EV where it had to withstand constant 
flexing.  It might be usable in motors, but I think (though I'm  not an 
engineer) that efficiency would suffer somewhat.

One thing to consider about the long term use of AL over CU is that
reducing 
bauxite to aluminum uses a lot of energy.  AL wire is currently cheaper
than 
CU for a given power capacity, but if energy costs increase
substantially, I 
wonder if that could change the equation.

Again, though, I don't see AL wire finding much use in EV wiring.  David

Roden - Akron, Ohio, USA
EVDL Administrator

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