KERN FFN-N Operating Instruction page 140

Pressure compensation
screw
Pressure compensation screw:
[1]
On the lower side of the balance there is a pressure compensation screw [1]
which has to be opened for the weighing process. Fasten the screw before
cleaning the balance.
FFN-N-BA-e-1121
Level balance with foot screws until the air bubble of the
water balance is in the prescribed circle.
Mains connection
Battery compartment
14