Xiaomi Mi Door and Window Sensor 2 Manual De Usuario página 7

3. A ach the sensor and the magnet to the fixed side and the movable side
of the area that can be opened and closed. It is recommended to install the
sensor on the fixed surface and the magnet on the movable surface, and
ensure the clearance between the two is less than 18 mm when the door or
window is closed.
Note: The surface the adhesive sticker is applied to must be clean and dry.
Please avoid dropping the sensor during installation, as it may easily
damage the body of the sensor.
The installation clearance can be measured with the help of the scale on
the back of the user manual.
Ensure the clearance is less than 18 mm.
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