Every so often, I’ll have a power blink that causes my PLM to get into a weird state. I can unplug it and plug it back in after about 15 seconds and it will work (sometimes after restarting the Raspberry Pi my Openhab runs on). The Pi is on a UPS, but the PLM is not, as I figure that would block the signals.
Is there a reliable way to query from a rule or via an item whether the PLM can still communicate with devices? Or whether Openhab can still communicate with the PLM? I want to make a “watchdog” that can detect the condition and “unplug” the PLM with a relay I’ll wire in.
Currently if the PLM gets in this state and I only reboot the Pi, I’ll get all sorts of exceptions in the Openhab log file.
I was able to operate the PLM behind a UPS. I believe that most low-end UPS’s will pass the voltage straight through while there is shore power detected
My PLM showed the same behavior (it just hung), and I thought it was power fluctuations. In fact the PLM’s power supply was going south. This is very common, sorry. I replaced the capacitors and have not experienced any strangeness ever since.
Thanks, I’ll try running it through the UPS. I know there was a power blink last night, since some other stuff also turned off. I know what you mean about them failing, though. The PLM that came with my dev kit already died. I hadn’t thought about replacing the caps… I may see if I can find it and give it a shot.