Re: X10 signals can be TOO strong!

[ddl@danlan.*com (Dan Lanciani)]

In article <u7i3o25pmcg42v8cp0co0dn8d75euuk7of@xxxxxxx>, MFHult@xxxxxxxxxxxxxxxxxxxxx (Marc_F_Hult) writes:
| On 14 Dec 2006 21:46:02 GMT, ddl@danlan.*com (Dan Lanciani) wrote in message
| <1335298@xxxxxxxxxxxxxxxxxxx>:
|
| >In article <qtdgh.203122$Fi1.110592@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
| JeffVolp@xxxxxxx (Jeff Volp) writes:
| >| "Alan Vogel" <avogel2@xxxxxxxxxxxxx> wrote in message
| >| news:6e5gh.30252$wP1.27181@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
| >| > It looks like the 30Vpp signals that appear on the MT1 and MT2 pins of the
| >| > triac are exceeding the triac's dV/dt spec.  These signals capacitively
| >| > couple to the triac's gate and turn it on.  Sensitive gate triacs
| >| typically
| >| > have higher dV/dt limits, but are probably not used in the modules because
| >| > they are more expensive.
| >|
| >| That makes sense.  The inductor in series with the triac should limit the
| >| dV/dt, but perhaps not enough.  I recall Insteon had to change an inductor
| >| to resolve their flicker problem.  I don't understand why this seems to
| >| effect modules running near their maximum load.
| >
| >Perhaps the heavier the load the greater the amplitude of the carrier
| >across the triac?

| Another possibility is saturation of the inductor core at high currents.

I like that even better.  One thing I wasn't clear on:  do the lights
flicker even when the switch/module is supposedly totally off?  With
cold filaments that should give the highest carrier amplitude across
the triac, and of course there is little/no current through the inductor.

				Dan Lanciani
				ddl@danlan.*com