Bob Fehrenbach <bfehrenb@EXECPC.COM> wrote:
>    When you ran 3 amps through 30 ga wire (33 cir mils/amp)
>    did you melt the insulation?    While testing wire wrap prototypes
>    without my glasses on (a clip lead on the wrong pin) I have had
>    wires glow for a while before they melted.  I think the power supply
>    swung up over 5 amps.

[Note: these comments aren't particularly directed to Bob.]

This is why bench supplies have adjustable current limiting.  You should
set the current limit to just above the expected power consumption, and
keep an eye on the meter or the CC (constant current) mode light.

For example, if you only expect the circuit to draw 500 mA, don't set the
current limit to 3 A.

I can't believe how many people try to debug prototypes using PC power
supplies and other such junk.  The usual explanation given is "but they're
so cheap".  Which only proves my point.  How many chips (and whole
prototypes) can you afford to damage rather than buying a decent bench
supply?

Every time that CC comes on, the supply has possibly prevented damage.
I've lost count of how many times it's worked for me, but I know that I'd
have blown up a few expensive boards if I didn't have it.

Cheers,
Eric