Copper vs Aluminum buss bars

[rival904 10+ year member]

So lets say we had 2 buss bars.

Both are 1.25in wide, .25in thick, and 5ft long.

One copper and one Aluminum, the aluminum one is 2024 and the copper is 110 alloy.

What would the current flow look like for each bar?

What about the resistance?

From everything Ive read, the Aluminum is 60% less conductive than the copper.

Click to read more...

 

[boostNbeer]

Its not 60%, but its significant enough that if you can afford the copper, you go copper

I use aluminum personally for all distro blocks/buss bars, 6061 alum though

 

[rival904 10+ year member]

According to the electrical contractors study book, its 60%

 

[loudjeta 10+ year member]

Go with the copper if its within your budget!! if your looking for some great copper I suggest these guys. same day/ 1 day shipping http://www.stormcopper.com/

 

[rival904 10+ year member]

I already know what Im going to use, I am looking for reasons other than "copper is a better conductor"

No one here knows the current transfer between the diff alloys of copper and aluminum?

 

[Street DreamsCC 10+ year member]

for normal 12v copper and alum are close to being the same. Copper you will get better current flow but you can use alum. It is when you start getting into 120/240v apps that you notice a bigger difference.

If you were really worried get thicker alum so you get more area for the current to flow.

But exact size to size copper is always better but can cost upwards of 2 times as much.

 

[Mr. Slate 10+ year member]

I always use copper in my builds:

Just looks better, lol.

 

[rival904 10+ year member]

Ok, riddle me this, thicker material would cause more resistance on an already poor conductor(compared to copper) would it not?

 

[Street DreamsCC 10+ year member]

I already know what Im going to use, I am looking for reasons other than "copper is a better conductor"
No one here knows the current transfer between the diff alloys of copper and aluminum?

you would have to do a side by side test. What one person might get is going to be different from what you might get.

 

[Street DreamsCC 10+ year member]

Ok, riddle me this, thicker material would cause more resistance on an already poor conductor(compared to copper) would it not?

sure and adding more power wire will cause more resistance too right....

going smaller might

 

[rival904 10+ year member]

sure and adding more power wire will cause more resistance too right....
going smaller might

Yea, but lets say you measure your voltage loss from the front to the back, and its 2V, add another wire and the voltage loss becomes 1V.

So adding resistance = gaining more usable voltage?

IE - two parallel 0 gauge cables will halve the resistance of a single 0 gauge cable (of the same length).

 

[PIITB Wut Wut 10+ year member]

i use alum, i have used copper tho...

basically what i have read is alum is 99.7% as conductive as copper... and aluminum is super light and doesnt rust like copper...

so weigh your options... i just made my copper bus bars tonight... 1 inch wide 3/4 tall and 5 feet long.

 

[rival904 10+ year member]

Do you have access to a meter? Can you meter with the alum bars vs the copper bars?

Where did you read that alum is 99.7% as conductive as copper?

 

[rival904 10+ year member]

Copper has a higher conductivity than aluminum. It is more ductile (can be drawn out). Copper has relatively high tensile strength (the greatest stress a substance can bear along its length without tearing apart). It can also be easily soldered. However, copper is more expensive and heavier than aluminum.
Although aluminum has only about 60 percent of the conductivity of copper, its lightness makes long spans possible. Its relatively large diameter for a given conductivity reduces corona. Corona is the discharge of electricity from the wire when it has a high potential. The discharge is greater when smaller diameter wire is used than when larger diameter wire is used. However, the relatively large size of aluminum for a given conductance does not permit the economical use of an insulation covering.

http://www.tpub.com/neets/book4/11e.html

 

[slim2fattycake 10+ year member]

That number is wrong. And both aluminum and copper oxidizes at close to the same rate.

Here is a conductivity chart with some other properties.

http://www.wisetool.com/designation/cond.htm