In order to ensure a high-precision test system, in addition to the use of high-precision A / D converters, other module design in the system also has a great impact on the overall system accuracy.

(1) The sensor is the core of the whole system. To obtain a reliable data source, attention should be paid to the installation method of the resistive load cell. The mounting surface of the load cell of the load cell should be smooth and tidy, without any oil film or film. The mounting base requires a higher strength and stiffness than the sensor itself. The mounting surface of the mounting base should be leveled with a level. Normal flat washers should not be used for installation and spring washers should be used. When applying force to the sensor, load it in the direction of the force applied by the sensor to avoid lateral or additional torque.

(2) The digital device and the analog device are independently powered, and the power supply is regulated, and a filter circuit is added to prevent the power supply noise from affecting the system. In order to prevent conducted high-frequency electromagnetic interference, shield beads are added to the sensor signal output terminal and the power line. When wiring the PCB, try to isolate the digital part from the analog part and isolate it digitally from the analog ground.

The system can operate stably, and the measurement results meet the accuracy requirements. The display resolution is 1/40 000. The data stabilization time is less than 1 s.