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Re: triac mains switch
Hi,
> > I've built one, it looked and seemed so simple, but I can't help smoking
> > one triac after the other when I remove my current limiting 1kW cloth
> > iron. :(
> What is the part number of the triac are you using?
It's from TIC226 series, a TIC226S (700V, 8A), switched by opto-copuler.
But that's solved now, Marco gave me a brilliant tip to use thyristor
switched solid state relays, so I can still have optical isolation
between mains and switch/timer device, but less faults and no need to
reinvent the wheel. A completely matching 26uF PFC for the 400VA NST was
also good to protect the new SSR from false switching.
The triac stuff didn't work out well at all. I would not recommend anyone
to be as stupid as me and use triacs directly on a transformer.... not
without a completely matching PFC cap anyway, which removes dV/dt
problems.
Dropping the triac control completely and using just a (mechanical) relay
for test gave a miraculous improvement in TC output. Somehow.
Now it's already 8" hot streamers into air from my 1.8" TC of exactly
equal height, with a very crappy spark gap indeed. 8-).
> > Also, before my last on-stock triac popped, I had a
> > 10uF PFC cap accross my 220V 2.1A, 8kV 400VA rated NST (does 10uF sound
> > reasonable, by the way?).
> Could be bigger. There have been formulae posted in the last couple of
> weeks
Darn. My mis-calculation. You're right, too small. C = 1/(w*Zin) = 26uF
was more like it...
thanks
> Regards,
> Malcolm
--
*************************************************
Jan Florian Wagner
http://www.hut.fi/~jwagner