[sdiy] Revisit - Minimum parts count switch de-bouncer.

[harry bissell]

Id like to add...

the cap is exposed to 120Hz AC ripple... but if you are going to take the
cap from full charge to full discharge you have MASSIVE ripple current and
expect an early death (the cap, maybe you too :^)

There is a difference between what you can 'get away with' and what is going
to be good for life, by design.  Sometimes #1 above is the ~right~ choice

H^) harry


Tim Daugard wrote:
> I'm between trips, so I have a few minutes.
>
> On the cap switch discussion.
>
> SWITCH
>
> Per my HVAC engineer father "Switch contacts are destroyed by the arcing
> when the contacts disengage. The intial engagment causes no problems. It is
> the continuation of the currents as you try to pull the contacts a part . .
> ." that burn the contacts / remove material.
>
> AS we are using the switch to charge or (in my case) discharge a capacitor,
> the current should drop significantly as time goes on, so the switch used
> should be okay.
>
> CAPACITOR
>
> Capacitors are exposed to currents a 120 times / second in a power supply.
> A capacitor goes through more cycles in 20 minutes than we may use in the
> life of the module.
>
> HOWEVER
>
> 1) The manufacture says don't do it.
>
> 2) Current depends on ESR.
>
> SO
>
> I will still try to measure ESR and discharge current soon (may have to
> wait till after the next trip) and maybe put a resistor inline with the
> switch. (agreeing with Na, Na-Na, Na, Ha Ha, Harry, Goodbye)
>
> Tim Daugard
> AG4GZ 30.4078N 86.6227W Alt: 12 feet above MSL
> http://home.sprintmail.com/~daugard/synth.htm
>
> And why do y'all post less than 50 messages a day when I'm here and over a
> 100 a day when I'm gone?
>
>
>
>
>