What is a gold bonded relay?

[randy1]

What is a gold bonded relay?

Does anyone know the details of a gold-bonded relay? Typically you here of silver contacts and I have to admit I have never seen a gold relay. I have a defective gold-bonded relay and i'm just hoping to replace it with a relay with similar current ratings. Any info would be appreciated.

thanks,
Randy.

[Cheller]

What is a gold-bonded relay?

As far as I know, gold bonded relays are simply relays with gold-plated contacts. Gold is used sparingly inthese so I don't think there is enough here to make them valuable.

The gold is usually applied in an alloy along with other valuable metals like silver and platinum. Gold is used in the contacts because of the electrical stability of this material. It is considered to be the least reactive metal and the yellow metal provides a low contact resistance over a long period of time.

They sometimes use gold electrical contacts for low voltage applications because they resist insulating oxide and tarnish so well. You don't see them often in standard industrial applications like motor starting and general relay logic. I think they are more of a specialized relay for low voltage circuits.

[randy1]

This is a picture of a gold-bonded relay that we have used in our plant:



These are the only gold-bonded relays we use and I was wondering the reasoning behind the choice. The application for this particular relay was controlling some valve logic, so I don't see what reason it was chosen by the manufacturer.

[randy1]

Oh yeah, and it is an: Arrow-Hart Cat. number MTU-004-20 with coil voltage 110-120 Volt

[Cheller]

I'm not 100% sure on your application, but for a few bucks it would be easy enough to swap out...

http://www.ebay.com/sch/Business-Industrial-/12576/i.html?_from=R40&_nkw=MTU-004-20