On 5/26/06, Steven Howes <steve@poundbury.com> wrote:
>
>
> Yea we were looking into mercury wetted ones but getting them as soon as
> we needed them was going to be tricky. We have since adjusted the circuit to
> switch it in a different manner. Perhaps i should look into the downsides of
> components before using them next time ;). Thanks to you all for your help.


Wetting current is another one that will get you. For any normal mechanical
switch, there is a minimum current to assure the contacts actually close.
Otherwise, they may from time to time go to high resistance values or even
open up entirely.

Mercury wetted relays were used a lot with audio circuits where there wasn't
any significant current flowing, for this reason.
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