Mysterioius X10 commands don't appear in log

I have a lamp on an appliance module that gets turn-on commands from somewhere. It responds to the Indigo commands for on and off at the programmed times, but it also turns itself on every few minutes with no commands from Indigo.

If I send the off command, a few minutes later the lamp is on again.

The weird thing is that the stray commands are not seen by the Powerlinc USB--they do not appear in the log.

I've replaced the appliance module and changed the house code and the unit code several times. Doesn't matter--it still gets extraneous turn-on commands from somewhere.

Any ideas?

Thanks,

Bob Leedom
Glenwood, MD

P.S. There is another controller upstairs that I no longer use. It's on a different house code. And anyway, I would think its commands would appear in the log if they were being issued.

[matt (support)]

Morning Bob,

The weird thing is that the stray commands are not seen by the Powerlinc USB--they do not appear in the log.

There are a couple of possible reasons for this: the X10 signal noise is localized to the circuit area that the appliance module is on, the PowerLinc does a better job at filtering out noise and only accepting real X10 commands, or a combination of the two.

I've replaced the appliance module and changed the house code and the unit code several times. Doesn't matter--it still gets extraneous turn-on commands from somewhere.

These are definitely the first two things I would try. Because changing the house/unit codes didn't help, I definitely think this is signal noise.

P.S. There is another controller upstairs that I no longer use. It's on a different house code. And anyway, I would think its commands would appear in the log if they were being issued.

It wouldn't hurt to unplug that controller to 100% eliminate the possibility that it is the culprit.

I'd try turning off potential noise sources (appliances and lights) that are on the same circuit as the appliance module. You might need a filter somewhere. Also try unplugging X10 modules (put any light switches in the power gap off mode) -- some X10 modules will send out X10 noise/commands if they are on their death beds.

Regards,
Matt

Matt's answer:
> It wouldn't hurt to unplug that controller to 100%
> eliminate the possibility that it is the culprit.

Well, this is wacky: when I unplug the other controller (in which I have cleared all commands--it sends nothing out), I can no longer control the strange-behaving lamp module from the computer any more at all!

I re-plug-in the old controller, and computer control is restored.

Still scratching my head....

Bob

[matt (support)]

Now you have me baffled. I have never heard of an extra transmitter helping the situation before.

Have you tried unplugging all of your X10 modules (except the extra controller and module in the "bad" location), and disconnecting (power gap off switch) all of your X10 switches? This obviously isn't a good long term solution, but it would be good to rule out a dying X10 modules as the culprit of the signals.

If, at this point, you can control the the appliance module and it doesn't randomly come on, then I would start reconnecting your other X10 modules until the problem resurfaces. Hopefully you could narrow down the problem module.

Regards,
Matt