I have experienced a puzzling (and quite upsetting) series of failures of assorted X10 wall switch modules, all exhibiting the same failure mode. Over a period of 1-2 months, SIX modules have failed, each at a
different time, three of them within one week. The failure mode is that they turn on, apparently un-commanded, and then cannot be turned off via X10 PLC commands nor even via their manual pushbuttons, nor via cycling their AC supply power. The three non-XPS3 modules all had an identical pre-failure symptom over a period of weeks where they would not turn off via their pushbutton after having been turned on manually via their pushbutton. During this pre-failure phase, they would turn off via X10 command, or after
repeatedly pressing their pushbutton, or in some cases after waiting 10-15 minutes and then pressing their pushbutton again. All or most of these modules were installed at roughly the same time, several years ago, and have worked apparently normally until they malfunctioned or failed recently. (Do they have some sort of "life expectancy" or "built-in expiration"?) In any case, I'm concerned that there may be some recent condition(s) that caused all these modules to fail within weeks of each other. Do you have any idea what might be causing this sort of failure? There have not been any storms here, and I don't believe there have been any power outages, surges, etc. But I'm concerned about replacing any more of the failed modules until the cause of failure has been identified and corrected. Can you help?
The modules involved and their applications are:
- (3x) XPS3 - each controlling a ballasted area light fixture.
- a WS13A - controlling a circuit consisting of two florescent shop lights and one 60-watt incandescent light
- a WS13A - controlling a circuit consisting of two CFL bulbs, one florescent shop light, and one LED shop light (the LED being a relatively recent addition)
- a WS467 - controlling a circuit consisting of one incandescent (yellow) "bug light".
All these modules are located in out-buildings, between 100' and 300' from the main circuit breaker panel, but on various branch circuits, all of which involve at least some overhead outdoor power wiring.
After removal, I "bench-tested" each module with a PHC02 Maxi Controller plugged into a power strip along with the module under test. Each module showed the same failure mode under these test conditions as they had when installed. I have replaced two of these modules with XPS4 modules; one of these new XPS4 modules appears to work OK, but the other does not respond to X10 commands sent from near the main circuit breaker panel. Prior to its failure, the WS13A module that it replaced
did respond to X10 commands sent from the same controller in its same location.
I also disassembled two of the failed modules (one XPS3 and one WS13A) for inspection and found no indication of damage - no burn marks (from arcing or burned-out components), no rust, corrosion, or oxidation, no de-soldered joints or loose connections, no melted parts, and nothing else that looked suspicious.
This situation concerns me that replacement modules also may fail, due to some thus far unidentified reason(s). Any ideas about what could be causing these module failures, or how to track it down?