copper vs aluminum

[wp7456 10+ year member]

Is it worth switching from aluminum to copper? I heard somewhere that aluminum is like half as conductive as copper. Is that true? I've been looking around lately but can't find any 2 gauge copper which is the most my amp will take.

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[allout13 10+ year member]

Is it worth switching from aluminum to copper? I heard somewhere that aluminum is like half as conductive as copper. Is that true? I've been looking around lately but can't find any 2 gauge copper which is the most my amp will take.

you can always use 1/0 and then use wire reducers to make it fit your amp

 

[pr-festiva 10+ year member]

find a local welding supply shop,

 

[jco1385 5,000+ posts]

what wire do you have? the only aluminum wire i can think of is stiff as fawk and is used underground/in houses. you may have tinned OFC (which looks a lot like aluminum) but i really doubt you have aluminum wire unless you were fuckin up.

 

[Cabin_Pressure 10+ year member]

Is it worth switching from aluminum to copper? I heard somewhere that aluminum is like half as conductive as copper. Is that true? I've been looking around lately but can't find any 2 gauge copper which is the most my amp will take.

You heard wrong. Theres not that^ much difference in the conductivity, copper has better heat characteristics. Aluminum wire will swell and contract more than copper when going through cycles. Usually you can just go up one size with aluminum wire to achieve the same amperage rating as copper.

 

[jco1385 5,000+ posts]

You heard wrong. Theres not that^ much difference in the conductivity, copper has better heat characteristics. Aluminum wire will swell and contract more than copper when going through cycles. Usually you can just go up one size with aluminum wire to achieve the same amperage rating as copper.

i think he saw the other thread where it says 1/0 copper = 2/0 aluminum

either way i really REALLY doubt you have aluminum wire in your car.

 

[allout13 10+ year member]

what wire do you have? the only aluminum wire i can think of is stiff as fawk and is used underground/in houses. you may have tinned OFC (which looks a lot like aluminum) but i really doubt you have aluminum wire unless you were fuckin up.

the cheaper knu is copper clad aluminum

 

[Korn4Life 5,000+ posts]

what wire do you have? the only aluminum wire i can think of is stiff as fawk and is used underground/in houses. you may have tinned OFC (which looks a lot like aluminum) but i really doubt you have aluminum wire unless you were fuckin up.

Isnt KNU KLM wire all aluminum with a copper coating on it?

 

[Korn4Life 5,000+ posts]

the cheaper knu is copper clad aluminum

Beat me to it

 

[TurdFergueson2 5,000+ posts]

Is it worth switching from aluminum to copper? I heard somewhere that aluminum is like half as conductive as copper. Is that true? I've been looking around lately but can't find any 2 gauge copper which is the most my amp will take.

Needs a Poll

 

[grassroots 10+ year member]

specific resistance of copper is 10.4. aluminum is 17.x (i can't remember exactly).

that's a pretty big difference...

aluminum is lighter than copper, but to get the same ampacity rating you need to upscale the wire size (like stated) so it kinda balances out.

you also gotta worry about aluminum wire pulling out of your amp or battery connectors since it swells and retracts with heat/cold (like mentioned).

and you should use nolox on terminations to keep aluminum from oxidizing.

copper is always a better conductor than aluminum.

edit: and depending on the insulation of the wire (which is a huge factor in how much amperage it can safely conduct) you have to use 3/0 aluminum to have the same rating as 1/0 copper wire.

 

[jco1385 5,000+ posts]

even the 1/0 CCA Knu wire can handle up to 250A IIRC.

but he has 2ga RF wire...

how does aluminum oxidize?

 

[grassroots 10+ year member]

even the 1/0 CCA Knu wire can handle up to 250A IIRC.
but he has 2ga RF wire...

how does aluminum oxidize?

it's just a property of the metal...

i'm an electrician and it's required to use nolox on all aluminum connections and terminations to prevent oxidation. none is needed with copper wire.

 

[jco1385 5,000+ posts]

Aluminium is remarkable for its ability to resist corrosion (due to the phenomenon of passivation) and its low density.....Corrosion resistance can be excellent due to a thin surface layer of aluminium oxide that forms when the metal is exposed to air, effectively preventing further oxidation.

i thought it was crazy hard to oxidize aluminum?? //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

and easy to oxidize copper... WTF homes? i don't understand that

 

[grassroots 10+ year member]

well what would i know (or every electrical contractor i've ever worked for) //content.invisioncic.com/y282845/emoticons/rolleyes.gif.c1fef805e9d1464d377451cd5bc18bfb.gif