Single-component sensors The load washer is an eminently suitable type of sensor for practical use. It consists of two quartz plates held under slight preloading between a base plate and cover plate, inside a hermetically sealed case. The measuring signal is picked up by an industrial electrode located between the quartz plates and conducted to the connector. Load washers are rugged and extraordinarily versatile. Thanks to the central bore, they can be fitted in screw connections for force measurement as well as being built into various types of structures and preloaded with a preloading screw. Where fitted, the preloading screw creates what is known as a force shunt. Here, part of the force to be measured flows via the screw and is not measured by the sensor. For accurate measurement of the sensitivity in situ, on-site calibration is necessary. Where a load washer is preloaded between two special nuts, this creates what is known as quartz force link. The preloaded sensor is used for measuring tensile and compression forces, e.g. in a linkage. Preloaded sensors, which come ready-calibrated, are easy to fit and can be used for measurement immediately. Low level force sensors for small forces are fundamentally different in design, with slim quartz bars clamped between the force-conducting parts. The piezoelectric effect of these slim bars offers around thirty times the sensitivity of the quartz rings in the load washer. Quartz force link Load washer Low level force sensors 10 www.kistler.com