joining aluminium to copper

[sledgehammer]

I've not had the experience but I've seen a couple of glimpses of aluminium conductors joined to copper. This was on to busbars and main mccb terminals etc. They'd used lugs I'd never seen before, they also looked to have had a compound or paste in them. Does anyone know much about this practice, the reasons and things to look out for etc. It was fairly large stuff obviously.

 

[telectrix]

i assume the paste is to help prevent dissimilar metal corrosion.

 

[Zebra Stripe]

As above,
I believe the process is called "Galvanic Corrosion"

 

[telectrix]

something to do with ions being stripped from anode to cathode, where the anode is the metal that corrodes. used in ships with a sacrificial anode to sacrifice metal instead of it coming off the structure of the ship.

 

[Zebra Stripe]

Hey, your good

 

[telectrix]

had a couple of boats, once. in a force 9, it's not a good idea to hit rocks. some fat use the sacrificial anode was then.

 

[Zebra Stripe]

Captain Telectrix and his sacrificial anode, hey think there may be a book deal there. Wish I had a sacrificial anode or possibly a goat, anyways two boats, I'm obviously not charging enough.

 

[scotsparky]

big question is are you sure it was Aluminium to Copper and Not Tinned Copper to bare Copper.

 

[Marvo]

We've used various methods, crimp fitting an appropriate lug to both the aluminium and copper wires and bolting together with paste then heavy duty heatshrink is probably the easiest. There's also crimped ferrules available that are designed for Cu-Al connections, google 'bi-metallic joints/connectors/ferrules etc. I've also seen the mechanically fitted lugs and ferrules that have a grub screw arrangement, haven't used them so not sure how good they are.

 

[Knobhead]

Antioxidant paste is what you need. It stops cathodeic migration. Or nip down the local chemists and buy a tub of Vaseline!

 

[shanky887614]

Antioxidant paste is what you need. It stops cathodeic migration. Or nip down the local chemists and buy a tub of Vaseline!

same reason people put Vaseline on car batteries?

 

[FAA Greenie]

I don't know why metals can't just get along together, it just seems petty. What's a few ions between friends? (unless you a are battery, then it's useful)...

 

[Knobhead]

same reason people put Vaseline on car batteries?

You can get a special gel for batteries.

I’ll give you two guesses what it’s made from.

 

[Tiny Spark]

Antioxidant paste is what you need. It stops cathodeic migration. Or nip down the local chemists and buy a tub of Vaseline!

Never used it for that but I have been known to put it on screws amongst other things
Always a handy thing to have in your box LOL