Jesse Lackey wrote:
> Hummm... I'm sure more knowledgeable people on piclist will chime in, 
> but as far as shorts and fuses ... what if a grounded metal object 
> contacts the pcb?  kerpow.  Or one of the AC devices fails as a short? 
> Are triacs guaranteed to fail open-circuit?

If a triac fails closed circuit, all it means is the power for that 
circuit is on.  I only have one leg of the A/C on this board.

> Personally, fuses are cheap and relatively small, why not use them.

Because an internal fuse requires someone to open up the case, rather 
than pressing the externally pressable breaker button.

I think I'll add a fuse on the input to limit the current across the 
traces to something I know they are safe for, but not fure each output 
to guarantee its limit.  I'll recommend the user add a breaker per 
output channel to limit to a safe value, or limit the input to be a max 
per-channel safe value.

--Michael
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