slighty OT: How long do relays last ?

[Harry Bissell]

Are those reed relays by any chance...?

the contacts can stick easily if you switch the slightest capacative loads. They can
often carry a amp or two, but will weld shut on make / break.

Most relays have no grease. Hermetic units would have none for sure !!!

Is it an AC or DC coil relay ?  If DC you should have a diode reverse parallel with
the coil. Ans be sure that the relays are truly de-energized. Some relays will hang in
with only 10% of the coil voltage applied.

Hopr this helps

H^) harry

Michael Buchstaller wrote:

> Hello Group,
>
> i recently discovered a pile of relays that i have acquired ca. 1985. They have
> been in my basement since then and look fine since they have been in their
> original carton since then.
>
> In the last months i began using some of them in DIY projects (OK, not for a synth,
> but for controlling my garage opener motor and for an automated PC controlled
> capacitor matching device).
> Surprisingly, approx. 9 out of 10 of the relays do work just fine, the others seem to
> hang trom tome to time (when i knock them with a screwdriver, they keep on going for
> some time befor hanging agein)
>
> Could it be possible that relays (as mechanical parts) have some grease drying up
> over time even when they were not used ? The relays are hermetically sealed ones
> fom Zettler (AZ 693-055-2) and i have gotten them directly from the factory, so they are
> not untested surplus units.
>
> Any hints ? Do relays have a mechanically finite lifespan ? (not the max. number of
> on/off cycles or contact wear)
>
> -Michael Buchstaller