human presence sensor SONOFF SNZB-06P

Tested human presence sensor SONOFF SNZB-06P

1 min read

Operating principle - radar, emits and receives a reflected response.

Advantages:

- More precisely detects the presence of a person in the room. This would be good in the bathroom, when someone is taking a bath, the radar will see it despite the infrared motion sensor (IR)

Disadvantages:

- Wired connection

- The radar detects any movement. When the bathroom hood is on, the radar will erroneously detect a person. A workaround is to use radar in tandem with an IR sensor. The IR sensor will be used when the hood is on

- The radar "sees" through walls. If you install it too close to the ceiling, the radar will "see" people walking on the floor above

- Trust of people. The radar emits radio waves at a frequency of 5.8 GHz. The documentation says that the radiation power is equal to or less than the power of ZigBee, but ZigBee consumes so little power that a small CR2032 battery can power the ZigBee radio module for more than 1 year. Why is an external 5W (5V 1A) power adapter used ?