I have a Minoston 800 Series Zwave Plug (using Hubitat C-7)
I'm using the plug to turn on/off a short string of LED "Christmas lights". The lights are powered via a 5 volt AC to DC power supply plugged into the Zwave plug. The whole string draws less than 3 watts.
The lights flash/strobe when the Zwave plug is OFF (they work properly when on).
The relay in the Zwave plug appears to be "leaking" when it is OFF.
The plug appears to have a solid state relay - I don't hear a click when it turns on and off.
Is the flashing just a result of poor engineering of the Zwave plug?
Is there a way to correct the flashing/strobing? Should I add a resistor in series with the lights?
So they run off a standard USB power brick? I would try a different one if you have one, it may just be something between those two devices causing the issue.
What driver are you using? Have you tried other drivers, like just the Generic Zwave Plug? I assume it loaded one of the built-in Minoston drivers when pairing.
You wouldn't think it could be the driver, but I had a Third Reality Bulb that would not turn off with the built-in driver, it would go very dim and flicker. Using the community Tuya Color Bulb driver fixed that issue, surprisingly.
Perhaps this device isn't a relay output, instead some type of solid state switch, likely a Triac. It could be this device doesn't like an electronic load on its output especially at such a low draw.
Options to move forward:
Swap it out with a ZWave on/off device with a mechanical relay
Swamp the load with another load in parallel. Plug in a 10W (or more) incandescent bulb in addition to the power supply and see if stability improves. Might not be a good answer (wasting 10+W to an unneeded bulb) but it will tell you if your switch module is load sensitive (i.e. fussy).
The plug is not turning OFF all the way and is still outputting probably a very ugly lower voltage sawtooth waveform giving your USB sufficient power to deliver 5v in short bursts.
I have a post on here somewhere with oscilloscope pics from a zooz 700 series. Solid state just can perform like a relay in all cases. This is why the devices list a minimum required load.
Adding an additional load in parallel on the 120vac side will resolve your issue.
Post Script.
Now the Zwave plug stays fully on and will not turn off - either by Zwave command or by pressing the button on the plug - so it looks like the plug hardware has failed
