Force-balance sensor is a load transducer which transforms force and weight to electric signal, applied the mechanism of balance scale.

This is the configuration of force-balance sensor. Weighing beam balances without product on scale pan. The weighing beam starts to incline when the weight is applied on scale pan.

The photo sensor detects the minute incline immediately.

The controller increases the current to electromagnetic coil in order to balance the weighing beam based on the detection result of photo sensor.

This change of current is directly proportional to the change of weight, this current change can be used as weight signal. The force-balance sensor does not detect physical change but change of current directly, it can achieve accurate and high-speed weighing.