I had a Sonoff POW connected to my deep freeze for the last 2 months. It continually uses 75-80w / 1.9kWh - which is fine.
From 1st April I noticed that every day, this would decrease (eventually 50w / 1kWh) ... until when I came home the other day, all my food was defrosted and ruined :( So I shut it down and bought a new freezer (hasn't arrived yet)
But last night, I was curious and decided to remove the POW from the equation - worked again and froze my food! I figured the POW may be faulty - and tried putting in back .... now it works 100% again and back to 75-80w / 1kWh.
My question - is it at all possible it's the POW ? Can it somehow limit power to the device ? Or do you think my freezer is dying ? Why would the power consumption change ?
There is no way to answer your question from a distance. Did the POW's output voltage drop along with the power? Did the compressor cycle times both in number or duration change?
My wild guess: The freezer malfunctioned and didn't come out of defrost cycle or it has a failing thermostat.