A typical load cell includes one or more force sensing elements, such as strain gages, which are configured as an electrical bridge circuit. A load cell includes a counterforce and at least one force transducer such as a strain gage. The counterforce is configured and disposed to support a load and to deflect in response thereto. The force transducer is mounted on the counterforce and used to generate analog electrical signals that are proportional to the load supported by the counterforce. Typically, the force transducer includes one or more strain gages, which are mounted on the surface of the counterforce so that as the counterforce is stressed and strained by the application of a load, the strain gages produce an analog electrical signal proportional to the load. A strain gage load cell is basically a metal structure subject to a load to be measured, with strain gages sensing strain in the loaded structure. The strain gages are connected in an electrical bridge circuit. Power is supplied acros one bridge diagonal, and an output signal across the other diagonal is used as an indication of the load on the metal structure. The strain gage load cell is one of the more common means of measuring force. It is a precisely machined structure which responds with a deformation to a given applied force. A strain gage bonded to a deformable element exhibits a change in resistance according to the degree of deformation, which results in an electrical signal indicative of the magnitude of the applied force. The output signal from a strain gage load cell derives entirely from changes in the resistance of the strain gages. Accurate load measurements require that the strain gages sense the strain in the loaded structure accurately, and also that the strains in the loaded structure are true measures of the load on the metal structure. In general, a load cell used in a measuring device or the like has a strain body having a movable portion and a fixed portion, and a sensor for detecting a displacement of a strain body caused by a load applied thereto. A result of the detection is converted into a weight of a measuring target object. A shear beam load cell comprises a rectangular beam of load cell quality metal alloy, which has one end arranged to be supported on a base in cantilever fashion, and a free end arranged to support a vertical load. Strain gages aligned to measure principal stress due to shear strain are bonded to both sides of the web, and are connected in a bridge circuit for measuring the vertical load applied to the load cell.

Many weighing applications require the use of multiple load cells in a single scale or in a number of associated scales. In heavy capacity applications, the load is distributed over usually at least four load cells and some applications may require sixteen or more load cells. The sum of the load cell output signals must be obtained to provide a signal representative of the total weight applied to the scale. In a typical load cell, four strain gages are attached to the surface of the counterforce and are electrically connected in a full wheatstone bridge configuration. The analog electrical output of the wheatstone bridge is the output signal of the load cell. Load cells may be used in combination with analog to digital circuitry for accurately measuring desired physical properties or conditions such as weight, gravity, vibration, acceleration, fluid pressure and the like. When load cells are used in combination with analog to digital circuitry, the measuring device may be considered a digital load cell assembly. One of the many advantages of a load cell is the lack of individual mechanical parts that are responsive to applied loads and therefore subject to wear from repeated use. The application of a load to the receiving end coupled with restraint of the opposing fixed end results in relative deflection of the elements in the parallelogram structure. The electrical strain gages are sensitive to the dimensional changes in the load cell structure and an accurate reading of the applied load is derived by external measurement apparatus.