GB/T 20730.2-2019

This standard provides specific guidance for the inspection and routine testing of industrial process control instruments that accept analogue input signals and produce two-state or multi-state output signals. It is applied by manufacturers and quality assurance personnel in the industrial automation and process control sectors to verify the performance and reliability of these instruments during production and before installation. The standard ensures consistent testing procedures for devices such as limit switches, alarm units, and on-off controllers used in manufacturing and chemical processing environments.