At 11.37 2011.09.15, you wrote:
>On Wed, 14 Sep 2011 05:44:06 +0000, xavier wrote:
>:: What do u mean by galvanic isolation?
>
>It means that that the input to your system is physically not connected to=
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>the output.
>
>You might want this if you have mains AC on one part of your circuit but=20
>for safety reasons the output side mustn't be directly connected.=20
>
>If your Pic is powered via a transformer (for example) then the dc side of=
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>the transformer is galvanicly isolated from the AC input side. If your Pic=
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>is power directly from the AC (using suitable voltage reducing techniques)=
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>the Pic would not be isolated form the 50/60 Hz mains and therefore if you=
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>were to touch it, you are in danger of giving yourself an electric shock=20
>(fatal possibly).

Would it happen even if one touches the lowered tension terminal, e.g. Vdd
pin of the PIC (+5V), assuming (this is important for me to specify) that
the Vss is connected to neutral, and not to the line..?

I don't want to use circuits without transformers, just trying to understan=
d
the phenomen.


>It can also (but probably not in your case) be used where equipment might=
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>have a voltage difference between grounds - this can happen when many=20
>pieces of equipment have to 'talk' to each other over great distances or=20
>between buildings like on a large industrial estate/site.

Yup, this is very important also e.g. to avoid ground loops.

Cheers,
Mario


>Colin=20
>--
>cdb, colin@btech-online.co.uk on 15/09/2011
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>Web presence: www.btech-online.co.uk =20
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