On Sat, 17 Jul 2010 23:27:46 +0200 Ralf Mardorf <[email protected]> wrote:
> On Sat, 2010-07-17 at 23:23 +0200, [email protected] wrote: > > The strange thing about that PC power switch is that it is > > almost never used. The rendering machines wake up by a LAN > > message from the master, and shutdown by remote control as > > well. They are never touched. > > That makes it more easy for particulate matter to hurt the switch. Using > a switch will shorten it's live time, but never using it will do it too, > because when you use the switch, also dirt gets hurt, not only the > switch. Hmmm. I would say the black deposit was almost certainly silver oxide, and silver contact switches are not suitable for zero wiping action - indeed the only safe ones I know of are gold ones. See, it's all your fault. No use means no wipe :) However I'm slightly puzzled. I confess to not knowing *precisely* the start-up operation of these PSUs, but wonder of the contacts are normally closed, and start signal is from their break action. Dirty switches and relays don't usually inadvertently close, but they very frequently randomly open or partially open, and that would fully account for the symptoms you saw. There was a time when us poor trainees had to learn all about contact materials, ratings, actions, yada yada :( Kids today don't know how well off they are :P -- Will J Godfrey http://www.musically.me.uk Say you have a poem and I have a tune. Exchange them and we can both have a poem, a tune, and a song. _______________________________________________ Linux-audio-dev mailing list [email protected] http://lists.linuxaudio.org/listinfo/linux-audio-dev
