Piezoelectric surface strain sensors, transmitters with integrated charge amplifier, ±20 … ±800 με / 9238B

The strain in the basic structure is transfered on the sensor via the two contact surfaces resulting in a change in distance. The sensor housing serves as an elastic transmission element and converts the change in distance into a force. The piezoelectric elements subjected to this shear force produce a proportional electric charge Q (pC). The strain transmitters integrated electronics then converts this charge into an analog voltage signal. The particular advantages compared with the familiar strain gauge technology are the high sensitivity, large overload protection and practically unlimited life time even under fluctuating loads. The measuring signal can be further processed as a relative value. For absolute value measurements (e.g. in N or kN), the strain sensor has to be calibrated using an appropriate reference. The sensor design allows the use in industrial environments. Excitation voltage and measuring cycle control, range switching and communications interface data are transferred to the transmitter via the same cable used to transmit the measurement signal.