Re: X10 signals can be TOO strong!

["Jeff Volp" <JeffVolp@xxxxxxx>]

"Alan Vogel" <avogel2@xxxxxxxxxxxxx> wrote in message
news:uuogh.5921$Gr2.922@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> The inductor in series with the load is there to limit di/dt.  It was
> probably required by the FCC to reduce EMI.
>
> I think this is all starting to make sense.  The highest di/dt transition
is
> when there is a heavy load and the conduction angle for the triac is ~4.16
> ms in from the zero crossing (50% dim).  This high current pulse must have
> coupled back into a high impedance node (either the zero crossing
detector,
> or the XTAL input pin on the uP).  Either way, the altered timing caused
> abnormal conduction angles which showed up as flicker.

Except for one thing:  The flicker continues, and becomes even more
noticeable as the lights are dimmed even more.  As they ramped down to max
dim, they would flash on every time another dim command was sent.  But
remember, these X10 signal levels are WAY above those expected in a normal
configuration.

I think the bottom line is that there is an acceptable signal level window
for these PLC devices.  Too low, and control becomes marginal.  Too high,
and dimmers can start to flicker.  The Insteon dimmers apparently misbehaved
at normal signal levels.  I found X10 dimmers can also misbehave when
confronted with signal levels several times higher than normal.

Jeff