Re: Triac Circuit Not working right ?

From: Robert Monsen (rcsurname_at_comcast.net)
Date: 11/24/04 

Date: Wed, 24 Nov 2004 21:12:51 GMT

Stacy wrote:
>
> I suppose the begging question which you can't answer is why would an
> intelligent electronics person put a schematic out there when it does not
> work ? Or at best is not really going to work on an ordinary Incandescent
> Light Bulb which it describes as the load?
>

There are *lots* of circuits that don't work on various web pages. There
are also lots of circuits that work, but only marginally, with parts
that may have different specs than your part.

I'm guessing that Tony Van Roon tried the circuit out, and for the triac
he was using (which is probably different than the one you are using) it
worked fine. The amount of current required by his triac was possibly
less that that required by yours.

Another flaw with the 'van roon' circuit is that the circuit is powered
at line voltage when the lamp is disconnected. If you touch it after
you've unscrewed the bulb, you'll get shocked. Many circuits put the
load on the high side (the Line side, black wire or small hole on the
plug) for that reason. The center tap of the socket (which is hardest to
touch) should be at Line, and the screw part should be at Neutral. The
fuse should also be on the Line side, preferably before the lamp itself. 

-- 
Regards,
   Robert Monsen
"Your Highness, I have no need of this hypothesis."
     - Pierre Laplace (1749-1827), to Napoleon,
        on why his works on celestial mechanics make no mention of God.

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