Zehnder Rittling Timer RF Manual page 19

Note: The Timer RF does not work if the battery has
been fitted incorrectly. Moreover, an incorrectly fit-
ted battery can damage the electronics.
fig. 2
Remove the battery
Lift the battery out of the holder on the (-) side using a
screwdriver (fig. 2). Follow the instruction for fitting the
battery.
EN - 19