I’ve had the VZM32-SN installed for two weeks today, and am getting a power delivered reading of 4.3kWh, which works out at a power usage of around 12W.
The attached lights (LED down lights rated at 24W total) are rarely on (hallway).
Just for the switch, that seems like an insanely high power consumption.
By comparison, I have a VZM31-SN (same switch without presence sensor) attached to an identical set of kitchen light (which are on much more than the hallway), and over (almost exactly one year), it delivered 11.2kWh, which works out at a much more reasonable 1.2W.
Assuming the rest of the switch hardware is similar between the two switches (which I don’t know, but why wouldn’t it?), that means the presence sensor components alone use around 10.8W.
For reference, the Aqara FP2 mmWave presence sensor uses only 3W.
I have measured the power consumption of the red version of these switches to be about 1.5 watts. I would expect the zigbee version to be similar maybe a little more (<=1.7w). A power draw of 1-2watts would be consistent with the heat these switches produce. Unless your switch is literally too hot to touch you likely have an error in your measurements. 10 watts of heat dissipating through the switch would make it CRAZY hot, like touch it and say ouch hot.
Update: I looked up data sheet of the HLK-LD6002 mmWave sensor that these switches use, they spec a power supply capable of delivering 3.3 watts and a nominal power draw of 1.98 watts when active. In practice I don’t think it draws anywhere near this numbers, but they do set an upper bound of what the mmWave sensor should be using.
Just tried a blue/Zigbee mmWave switch plugged into a Wanf watt meter, it was paired with my Zigbee network but had no load connected. Measured a similar 1.3-1.5W. It didn’t seem to make any difference whether the switch was on or off or what the dimming level was set to.
This looks like Home Assistant. Is this ZHA or Z2M? I know in Z2M we had to add a divisor to get the summation calculated correctly. It’s possible that’s missing in ZHA.
warm to mildly hot to the touch is normal 80-100f (30-38c). If there was truly 10watts being used by this switch 24x7 based on some back of the napkin math I would expect a surface temperature in excess of 90-100c ~200F. Which is what I mean by ouch hot.
The switch incorrectly reports its divisor as 100 instead of 1000. This will be fixed in a future update. Z2M, Hubitat, and SmartThings have it hard coded but I don’t know if that is possible by ZHA.
Seems this doesn’t need confirmation, but I just noticed my home energy report in home assistant with come crazy values for my office switch (installed mid Jan) and was coming here to check it out.
Home Assistant. ZHA. Controlling 4 grouped LEDs reading out 50W combined at 100%.
@EricM_Inovelli - any rough timing (days, weeks, a month+) to plan for for the firmware update? For now, I’ll just remove from my energy report.
