James Tu wrote:

> I will be using two 24V/10A power supplies.
>
> The PCB traces for the Power and GND is about 1/4" wide.  I soldered
> stranded 16 AWG(speaker wire to through-plated holes in those traces.
> The
> PCB holes were slightly too small, so I took used a drill to enlarge the
> holes slightly.  I cleaned up the PCB with compressed air and some
> water...and dried it.
>
> I connected molex pins to the end of each pair of wires.  I then
> proceeded
> to test continuity from the molex pin to my power and gnd traces.
>
> (I also have two 330uF polarized capacitors connected between Pwr and gnd
> of each power supply...these are actually for the IC's that the power
> supply will be powering.)
>
>
> What I'm seeing is a little strange.
>
> I touch the multimeter lead to the power molex pin and then I touch the
> other multimeter lead to the power trace on the PCB...everything is fine
> I keep the multimeter lead on the power molex pin and then I touch the
> other multimeter lead to the GND trace...continuity beeps for about
> half a
> second!  After that, when I touch the GND trace, nothing...
>
> I touch molex gnd and then GND PCB trace...continuity.
> I keep molex gnd and then touch power PCB trace...again continuity for
> about half a second.
>
>
> I'm guessing that the capacitors are the culprits here...why am I getting
> continuity beeps for traces that are seemingly unconnected except via the
> two capacitors?


Yes, you're just getting a reading while the capacitors charge up via
the meter!
David...

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