When a weight is applied to the weighing pan (1), it
moves down, guided by the parallel lever system (5). The
motion is transferred by the transmission lever (3) with a
specific ratio. A position detector (7) detects the displacement
x of the transmission lever. The position signal is
the input of the controller, which outputs a current I
through the coil of the electrodynamic actuator (8). The
resulting electromagnetic force compensates the
Concerning uncertainty of measurement and achievable
resolution, balances based on the principle of electromagnetic
force compensation represent the state of the art.
In Fig. 1, the schematic setup of an EMC balance is
depicted.