random x10 switch on/off

[sandy16]

The last posts I found on this were 2005-2006 but I seem to have the same problem.  I use AHP and have a house full of x10 modules and switches, all of which work beautifully (and have for years) until just recently one three-way switch seems to have a mind of its own and goes on randomly.  The others still work great.  Also, it won't work with the AHP but works fine with the on-off remotes.  I've changed from the old switches to the new ones, from immediate on-off to slow on-off ones but the poltergeist in that particular room persists.  I've changed codes, numbers, put two things on the same number (only the "evil" twin pays no attention while the "good" twin continues to follow directions....all to no avail.  Older posts suggest "modifying" the switch.  Since I have no idea what that is or how to do it, I seek help here for possible answers.  Other modules in the same room and/or on the same circuit breaker in the hose work just fine.  Help.

[dhouston]

When did your electric supplier install a 'smartmeter'?

[sandy16]

What's a smartmeter?  There were two things installed in the circuit breaker box but that was about a year ago; one was a PZZ01 250A Filter and the other an XPCR coupler repeater.  The random on has been occurring only for about a month or so.

[Brian H]

A Smartmeter is the power companies electric meter on the outside of you house.
The old fashioned ones are being replaced by intelligent ones that can do things like send date back to the power company.
One particular model seems to send data that also triggers X10 modules to do strange things like go On and Off all on their own.

[dhouston]

What's a smartmeter? 

See this thread...

• http://forums.x10.com/index.php?topic=22508.0

Do you hear a motor (e.g. furnace blower) starting at the time of the random events?

[Noam]

The random on has been occurring only for about a month or so.

Has anything changed in your home in the past month or so?
Any new electronics (computer power supplies, TVs, cell phone chargers, etc. have all be known to possibly cause problems with X10 at times)?

[sandy16]

Brian - thanks, I'll check; it would be nice if that were the problem
dhouston - thanks; no motors, other lights, furnace, etc., simultaneously
Noam - nope but thanks

The only other thing I can think of is a new neighbor just moved in about the time it began (separate houses but same power line); she has no x10 stuff, but how might I go about checking to see if there might be something else she has that may be sending signals.  However, even if that is the case and her signals are turning my switch on-off, why would it have stopped paying attention to my system's signals.  I would have thought it would have just responded both to hers and to mine but it stopped liking me when it fell for someone else.

[sandy16]

Now I'm even more confused.  I found an old mini-timer. and tried it with the guilty light, bypassing AHP.  It controls the light just fine.  What does that mean since AHP controls all the others OK?

[Dan Lawrence]

Try getting rid of mini-timer and see if AHP will control that switch properly.

[Brian H]

Mini-Timers power line transmitter may have a higher output than the CM15A.
If the power lines are marginal to the problem modules. The Mini-Timer may work and the CM15A not work.
Also possible the problem modules are starting to fail.

[JeffVolp]

X10 powerline problems all come down to signal-to-noise ratio.  There are likely loads in your electrical system that are reducing signal levels and making them marginal.  And there may be a noise source near that misbehaving switch.

As Brian said, the Mini-Timer may have a stronger output than your CM15A.  And the load from its transmitter would have reduced the background noise level slightly.  That could very well be a factor if it was plugged into the same circuit as the offending switch.

Jeff

[dhouston]

Older X10 devices had about twice the output level of any newer X10 device designed from the introduction of the CM11A forward. There are some measurements at...

• http://davehouston.org/x10-sig.htm

You may just have a signal sucker in the path and enough of the higher level mini-timer signal survives while the signal of whatever you use with AHP does not.

[dave w]

Now I'm even more confused.  I found an old mini-timer. and tried it with the guilty light, bypassing AHP.  It controls the light just fine. 

You plugged the Mini Timer in to same outlet that the CM15A is using, correct?

[sandy16]

Thanks very much everyone.  Here's where it stands:
Dan - the minitimer has just been pulled out of the mothballs and hadn't been used or plugged in in years until I just tried the experiment to see if it would work where the CM15a would not
Brian - I tried replacing the old switch with a new (never been used) PLW02 and then a new XPS3-IW; same results with all three.  Random on-off (though usually some time in the mid-morning hours after I've gone to work) and paid no attention to the CM15A settings.
Jeff - I agree there's something in/on the line that's sucking the signal but wish I could figure out what's giving a strong enough signal to turn it on when it feels like it
dhouston - I agree.

My next project is the leave the CM15A on one house code, change the switch to a different house code, unplug the mini-timer and see what happens.  If it at least stops the random on-off, I'll then try plugging in the mini-timer using one house code and leave the CM15A on a different house code.  If all that works, I may try using two different CM15As.  I've also looked into Control4 but it's prohibitively expensive and I can't do it myself (they require certain electricians).  If I can't get this to work, any suggestions as to other systems, though I've been using x10 for over 25 years with no problems.

[Noam]

...If all that works, I may try using two different CM15As. 

If moving the switch to another housecode works, why not just switch *everything* to the other housecode?
I don't remember if you mentioned this, but does AHP's event log show any commands being received to turn that one light on at the "random" times?