Aluminum to copper DIN rail connector - Page 1
Forum section: electronics / beginners

author: mike_mike
author_rank: Super Contributor
timestamp: March 03, 2024, 12:46:41 pm
content: Hello, I am new to electrical working, I want to learn a new course, but I can't find anywhere if the DIN rail connector from the attached images can connect copper to aluminum ?In the datasheet it doesn't specify anything about copper or aluminum...

author: Terry Bites
author_rank: Super Contributor
timestamp: March 04, 2024, 08:32:13 am
content: Its ok to join them but if the joint is subject to atmospheric moisture electrolytic corrosion will occur.Copper becomes the cathode and the aluminium becomes an anode.Try to achieve "gas tight" joint.

author: Gyro
author_rank: Super Contributor
timestamp: March 04, 2024, 10:17:58 am
content: Wago make a contact paste for Aluminium -Copper connections. It's for use with their wire connectors but it would probably suitable for DIN rail connections in harsh environments too...https://www.wago.com/global/accessories/syringe/p/249-130

author: mike_mike
author_rank: Super Contributor
timestamp: March 04, 2024, 10:50:23 am
content: @Gyro, I am already using that type of Wago connector and the paste for it.Do you have any information about the lifetime of that paste, after the aplication ?I was wondering about a connector that doesn't need any paste, probably it is hard to find one in local shops.

author: calzap
author_rank: Frequent Contributor
timestamp: March 04, 2024, 05:40:23 pm
content: The silver-colored contacts on the device in the picture are zinc-plated steel. It's fine for copper contact. If it's in a damp or corrosive atmosphere, the zinc may wear off, and then steel to copper contact could be a problem.Mike

author: Gyro
author_rank: Super Contributor
timestamp: March 04, 2024, 08:26:39 pm
content: Quote from: mike_mike on March 04, 2024, 10:50:23 amNo, I'm afraid I don't. Presumably as the non-lever variant of the Wago connector is maintenance free, the paste doesn't degrade significantly. I really can't say for sure though.

author: mike_mike
author_rank: Super Contributor
timestamp: March 07, 2024, 06:08:15 pm
content: I found some information about the copper and aluminum connection and I wanted to share it with you:Connections for joints or derivatives between aluminum conductors and between copper conductors and devices must be made only by special clamps with ribbed clamping surfaces and elastic elements, by pressing with appropriate tools and special connecting elements, by metallization associated with gluing or welding.Before the execution of the connection, the ends of the aluminum conductors needs to be cleaned of oxides.The information is from the normative.

author: JustMeHere
author_rank: Frequent Contributor
timestamp: March 07, 2024, 06:19:35 pm
content: Here's a similar device that says it does work with mixed wire types.https://www.amazon.com/King-Innovation-95125-AlumiConn-connector/dp/B003ZFUHOG

author: tooki
author_rank: Super Contributor
timestamp: March 07, 2024, 06:35:49 pm
content: Quote from: mike_mike on March 03, 2024, 12:46:41 pmWait, is your concern that the metal inside the terminal block itself is aluminum? Nah, nobody will do that -- you use copper for conductivity, or steel to save money. But since aluminum is more expensive than steel, and weaker, there's no sense in using that instead of steel.Of course, if that is your concern, you can avoid that worry by simply buying a proper name-brand product instead of no-name crap. Wago, Phoenix Contact, Weidmüller, ABB, Siemens, Schneider Electric, just to name a few.Also, do yourself a favor and get modern terminal blocks with spring terminals, rather than screw terminals. They save tons of time and effort.

author: mike_mike
author_rank: Super Contributor
timestamp: March 07, 2024, 07:01:48 pm
content: Quote from: tooki on March 07, 2024, 06:35:49 pmNo. My concern is that the metal inside terminal block is compatible with aluminum.I saw a electrical panel (inside a house) where is used aluminum and copper wires. The aluminum was connected with copper using the connector from the attached image.Also, I saw a aluminum and copper connection at outside, made using the same type of connector, only bigger size. Please have a look at the attached photos.

author: Gyro
author_rank: Super Contributor
timestamp: March 07, 2024, 08:24:54 pm
content: In those two use cases, I wouldn't hesitate to change them to Wago connectors, preferably with the paste but they would probably be safer even without. The second image looks like an outdoor location. For that, I would provide environmental protection by enclosing the connectors in a Wago Gelbox. That ought to seal against any moisture induced corrosion.Btw, from the white insulator, that looks like an outdoor span, is it supported by a galvanised steel wire? I don't think Aluminium is suitable for unsupported spans.

author: tooki
author_rank: Super Contributor
timestamp: March 08, 2024, 12:15:10 pm
content: Quote from: mike_mike on March 07, 2024, 07:01:48 pmOh ok. Just making sure.Sorry you have to deal with that aluminum wire. I’d still go with quality terminal blocks and use WAGO’s paste.