I'm installing a hydroponics setup for a restaurant to grow microgreens etc, it's mostly gone fine (got ~15 4PMs running without issue, all running a very similar mix of pumps, lights, and fans)
There's just 1 of the 4PMs that is causing me no end of issues with crashing, and it's doing it in a way that's really puzzling me:
- According to the logs, it seems that a ~50w pump switching off is the cause
- The 50w pump has a snubber already.
- Every output has a snubber already.
- Other 4PMs are switching the same make and model of pump without issue (although those other pumps run at slightly lower pressure)
- It's not a reliable crash: It seems like it depends on other things being true like the main room AC running (which is connected to the same distribution board but not controlled by Shellys)
- According to the power consumption logs when the crash happened, 1 of the channels powering LED lights managed to stay online until it was switched off by the control server at the correct time 3 hours later, while the other 3 channels switched off and stopped reporting power consumption at the moment of the crash.
Could this be the AC causing issues?
The crash only happens every 10 days or so, during which time the suspect pump will have switched on and off every 4 hours, so I don't think that it's necessarily a faulty 4PM.
I've got a workaround but I fear that the workaround will lead to eventual damage to the 4PM unless the root cause is addressed. (workaround is having control server check for condition where an Output is supposed to be On, then check the power consumption on that output: If it is 0, reboot the 4PM remotely)