Just wanted to share a solution I rigged up to monitor an older finicky standby generator to make sure it was doing its weekly exercise.
I put a repeater zigbee outlet (old lowes iris) in the corner of the garage near the outdoor generator to extend my range.
I removed the battery from a samsung multfunction sensor and purchased a cheap step down DC converter online. 12V DC to 3V DC. I soldered that into the sensor battery contacts and wired it into the 12V circuit on the generator (can use accessory 12V cigarette lighter style outlet or wire directly). I stuck the sensor to the inside of the generator casing put of the weather.
I set up automation with alerts to text and alexa announcement when vibration starts and stops. (I can also check temperature inside the generator case whenever I want to).
Now every week I know when/if the generator starts and stops and how long it runs. Plus, I never have to worry about winter killing the sensor battery, As it’s running from the 12V car battery that the generator circuitry keeps fully charged.
Hope this helps or inspires someone else.