copper windings, aluminum windings

[Nayov]

Tearing into my Chinapion (Champion) generator, I discovered that the windings on the rotor are a beautiful copper color, but in actuality the wire is made from aluminum (not sure about the stator). So - does this amount to a hill of beans and it's merely a blatant case of cost cutting, or are there real performance variances between CU and AL? I know that CU is a better conductor of electricity than AL, but do quality generators (Honda inverters) use copper? Do car alts use copper in their windings?

also:
Only 12V flow throw rotor windings as measured at the brushes (normal).

 

[Quest]

Most gennies I've worked on so far are on Cu windings. I've came across certain domestic brand name welders on Al windings plated with Cu...

Cost-cutting? Perhaps. I know Al has issues such as oxidation (upon termination points, as in certain early 70s housing construction codes up north in Ca where houses are wired using Al wires, and may lead to arcing as it ages....yadda..yadda..yadda..

But is this a concerning issue? Well, depends on how it's being used/handled. I know some older bldgs in downtown area: their transformer(in the basement) 3-phase lead-in wires (to the breaker box) are still running on Al stranded wires...and local hydro technicians have to use deoxit paste whenever they service it (vault has to be cleaned/serviced/checked every 2 ~ 3yrs time). Some local residential overhead lead-ins are made of Al wires also, and deoxit paste must be used on the master breaker joint.

All car alternators I've serviced so far are on pure Cu windings.Not aware of Al windings on cars so far...

Q.

 

[turtlevette]

I don't see why it would matter. The AL wire would have to be a touch bigger to have the same current carrying capacity. Years ago AL wire used in residential applications corroded at the compression connections causing problems.

 

[Shannow]

size for size, copper is always better than aluminium, but make the aluminium bigger, and it can be as good.

Does that make sense ?

Places where it matters (like alternators, power station generators), the conductors are copper

 

[kschachn]

Except for the transmission lines of course. Those are all aluminum, plus all the heavier gauge wires in aircraft.

Aluminum is fine as long as it is installed correctly using the proper terminations. If the wire looked like copper in your alternator, it may be copper-clad aluminum.

Originally Posted By: Shannow
size for size, copper is always better than aluminium, but make the aluminium bigger, and it can be as good.

Does that make sense ?

Places where it matters (like alternators, power station generators), the conductors are copper

 

[Shannow]

Like I said, the places where it matters.

Generator rotor and stator are copper. Once you get to the terminal chamber, the PIB is aluminium to the Generator transfomer, which goes copper again, then into the transl=mission line swhich are steel cored Al...shifting current is different to the requirements inside power equipment, where size and electrical performance is critical.

 

[Donald]

At lot of jumper cables for cars are now copper plated aluminum.

As copper gets more expensive, companies will find ways to use other metals.

Something like (USA) 1/3 of the known copper is in mines, 1/3 in use and 1/3 in landfills.

At some point when the commodity price is high enough and the technology is there, we will mine landfills for all the stuff we thought was useless.

 

[djb]

Using aluminum in windings could be problematic.

Aluminum is much less thermally and electrically conductive.

This is no problem with power lines, where volume isn't an issue. The lower cost and lighter weight (and did I mention lower cost and lower cost?) are far more important. With a thick enough conductor and few end connections, corrosion isn't an insurmountable issue.

But in a generator, reduced conductivity is really going to impact efficiency and size. To get the same magnetic flux you'll have much higher resistive losses, which now has to be cooled in the face of reduced thermal conductivity. Or you can build a bigger frame and have higher magnetic losses. Aluminum is lighter, but you'll lose most of that advantage building a larger frame.

 

[Nayov]

Now you guys have me wondering if my aluminum wire is indeed copper clad. If so, I'd sleep better (well not really...it doesn't matter in grand scheme of things, I guess).


By the way, my rotor failed because the wire to the terminal (rotor) for one of the brushes separated. I wonder now if it didn't fail due to corrosion as mentioned above, but it's a 1 year old generator (3500W).

 

[nitehawk55]

Under warranty ? Did you contact Champion before you tore it apart ?
I have read that their customer service is very good .

 

[cronk]

I have the Champion 3500w/4000 surge generator.
I think I have had it around 5 years, and it has been fantastic.
I cant remember what the warranty is, but give Champion a chance, they are good people to deal with (headquarters are in California).

 

[Nayov]

Warranty - yes. Receipt - no (lost). That's why I had to mess with it.

 

[webfors]

Interesting. I keep my CPE 3500w gen outside during the winter with a tarp on it. I wonder if I'm doing it a disservice from a corrosion perspective. Maybe build a nice breathable box?

 

[cronk]

Did you call them? I needed a air filter and cover for mine (lost it) And the part were reasonable and they stocked them right in California. Don't know if it would be economical on a major component like that.

 

[Nayov]

Amazing news! Well, for me that is. I hesitatingly asked if a cc transaction receipt would be suitable. He said no problem. I found it, but the transaction just said "Tractor Supply, $314" with no transaction number or description, so for all he knew I bought $314 of rabbit feed. I emailed it with little hope of acceptance, but not 2 minutes later he called me ("Just as I was about to leave for the day, but I wanted to take care of this for you right away.") and said he was sending out a new rotor right away. Fantastic customer service from Champion. Now I don't have to worry if my amateur soldering job will hold up.

 

[cronk]

Thats great news!
My personal experience with their customer service has been fantastic. Its good that they took care of you, I'm sure that treating people right like that has earned them customers for life, and rightfully so!

 

[webfors]

Excellent news! That's top notch CS IMO.