Re: Dimmer Differential

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi Luc,

I finally see what you mean now *:-))

A 1mS delay or instability is a bit of a concern on a finely tuned LTR coil
but not a "big" problem.  It would tend to cause a little instability.  I
am not sure what causes it but maybe modeling could predict the effects.
It should be looked into and eliminated if it can be.  I assume the diac or
trigger in the dimmer is more sensitive in one direction than the other...

Cheers,

	Terry

At 01:13 PM 10/25/2001 -0400, you wrote:
>Hi Guy,
>
>Couple of week ago I posted here that I used a
>"dimmer-cap-ignition coil" circuit to drive a fluorescent as
>strobe to checked a sync motor I rebuild. The result I got was a
>double pattern, many possibility existed that could cause this
>double pattern. The first 2 things I suspected was bad bearing in
>the motor or problem with the dimmer circuit. With the help of
>Terry I finally find that the problem come from the dimmer
>circuit. If you check the dimmer reading from a previous
>experiment by Terry you'll see that the conduction on the
>negative part of the 60Hz cycle is later than on the positive
>part:   
>
>http://hot-streamer-dot-com/temp/CoilTest/ACin3with20uFcap.gif
>
>By the number of degree I have between the 2 patterns on my sync
>motor I calculated around 1 mS of difference, in the Terry
>reading I calculated around .7 mS. It probably could explain
>Partially why some of you report erratic firing with TSG, I
>remember Marc reported that he have only 60 pulse/seconde in his
>first attempt with the TSG, that could be part of the explanation.
>
>I'm sure that for most the time this condition is not a problem
>in tesla application, many people have great success with TSG.
>
>This should raise a question: Is this difference stay the same
>independently of the position of the adjustment knob on the
>dimmer, is all dimmer are the same regarding this delay and is it
>a condition cause by the dimmer itself or by the "cap-ignition
>coil" part of the circuit ?
>
>Cheers,
>
>Luc Benard
>