Aluminium Busbar

[rahul9355]

Hi,

I am very much curious about why not?

 

Many people talk about difference of density and price of the Aluminium and Copper.

 

Only conductivity of aluminium is 62 %IACS whereas Copper has 101%IACS.Also some mechanical as well as thermal advantages with copper.

 

But still with increased cross section of Aluminium you can save lot of money but people are not doing that and why?

 

Are there any hidden problems?

 

If I am using 10x80 Copper for 1250 A normal current and 25 kA Short circuit at 12 kV and if I want to use aluminium for the same what size I shall look for?

 

Thanks

[marke]

Hello rahul9355

 

Welcome to the forum

 

Yes, you can use aluminium as a busbar material and it is certainly done. I have used busbars made out of aluminium for years without problems, but there are potential issues with the termination and the same way that there are issues with terminating aluminium cable.

 

The problem is that Aluminium is very active and quicly forms an insulating oxide layer on it's surface. This adds resistance to the joint resulting in heat tec. Additionally, if you have copper and aluminium in contact, you will get an interaction and problems.

 

If you are terminating to aluminimu, you must first scrub the oxicde off the surface and coat the joint surface with a jointing grease to prevent the air from getting to the surface. If you do not coat the surface within 30- seconds, the oxide layer will have formed enough to cause a problem.

 

Well tinned copper can be jointed to aluminium, but there are special jointing thimbles and components to help in this regard.

 

Best regards,

[rahul9355]

How about cold weld?You can weld copper and aluminium?

So terminals can be still of copper where majiority will be aluminium.

 

lso how mucs Cross section you increased with success.

 

Thanks

[Guest]

hi mark,

can i get some information regarding Energy efficient induction motors the latest innovations? plz

[Guest]

Just mentioning this for interests sake.

Schnieder electric use an aluminium busbar system in prisma p, which has one face which has a rough bonded copper surface the rest of the bar appears to be anodised or coated., its very cool and very light.

 

Another thing I have seen is used by Banyard from the UK, who make induction heaters. They have a busbar which has an aluminium core and copper on the outside, I believe it is extruded that way and hence has no chance of oxidisation once produced.

[mariomaggi]

Hi,

They have a busbar which has an aluminium core and copper on the outside

I don't agree with such solution. At the end of product lifecycle it is costly to separate copper from aluminium for recycling.

For some high-temperature applications, aluminium busbars could be Alumite-coated (this is an hard-anodizing process) to improve natural cooling by infrared emissivity. On joints Alumite coating must be removed by tools.

 

Regards

Mario