PJ wrote:
.....
>> 2 - the Snurra kontaktor sensor pin on your hi-V header will
>>     direct noise straight into the PIC from external sources,
>>     see "1" for fix; you might also need an optoisolator
>>     or more robust filtering on this particular line.
>
>hmm, true that line pair goes almost 700mm offboard.
>And its near to a few 380vAC switches going off/on every 5-15 sec.
>
>Still the transients cant go in this way throught the pic and
>out to the output pin of the 7805 ??? (thats where I saw
>them on my scope)


In a ckt like this you will have transients all over the place,
and to be most safe you also need protection all over the place.
The kontaktor sensor pin has absolutely no protection in your
ckt, and it connects to a 28" long antenna that runs straight
out to where the transients are being generated. I think this
is asking for trouble.

- dm

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