Piezoelectric Force Sensor The CL-YD -series Piezoelectric Force Transducers relies on the piezoelectric principle exhibited by quartz. Under load, quartz crystals produce an electric charge proportional to the mechanical load applied: the higher the load, the higher the charge. Thus, in piezoelectric force transducers, quartz serves as both the spring element and the measurement transducer. Added IEPE circuit, outputs the voltage signal directly.Specifications on single axial force sensor