A force sensor used in weighing scales, known as a load cell. Based on the principle of the resistance strain gauge, it can convert the gravitational force acting on the object being measured into a measurable output signal at a certain ratio. The performance indicators of a load cell mainly include linear error, hysteresis error, repeatability error, creep, zero temperature characteristics, and sensitivity temperature characteristics, which are affected by gravitational acceleration and air buoyancy at different locations of use.

 Traditionally, load cells are collectively referred to as weighing sensors and force sensors, with their metrological characteristics evaluated using a single parameter. The old national standard combined two types of sensors, "weighing" and "force measurement," which have completely different application objects and environmental conditions, without distinguishing between testing and evaluation methods. The old national standard had a total of 21 indicators, all tested at room temperature; and the accuracy level of weighing sensors was determined using the larger error among six indicators: nonlinearity, hysteresis error, repeatability error, creep, zero temperature additional error, and rated output temperature additional error, represented by 0.02, 0.03, and 0.05, respectively.

A force sensor used in weighing instruments. It can convert the gravitational force acting on the object being measured into a measurable output signal at a certain ratio. Considering the influence of gravitational acceleration and air buoyancy at different locations on the conversion, the performance indicators of a weighing sensor mainly include linear error, hysteresis error, repeatability error, creep, zero temperature characteristics, and sensitivity temperature characteristics. In various weighing instruments and mass measurement systems, the comprehensive error band is commonly used to comprehensively control the accuracy of the sensor, and it is linked to the weighing instrument error band (Figure 1) to facilitate the selection of a weighing sensor corresponding to a certain accuracy weighing instrument. The International Organisation (OIML) stipulates that the sensor error band δ accounts for 70% of the weighing instrument error band Δ, and the sum of the linear error, hysteresis error, and errors caused by the influence of temperature on sensitivity within a specified temperature range of the weighing sensor cannot exceed the error band δ. This allows manufacturers to adjust the various components that constitute the total measurement error, thereby achieving the desired accuracy.