The Refining-Chemical Integration Project of CNPC Guangdong Petrochemical Branch is a national key project for implementing the GBA Strategy and also a refining-chemical integration project with the largest construction scale in China so far, which may produce a full line of petrochemical products. CYG Contron provides a centralized control and visual comprehensive anti-misoperation locking system for this project, a reliable line of defense for the safe operation of the project. The system integrates multiple functions such as five-protection locking, video surveillance, earth wire management, strap management and remote-control locking. It is a successful practice and application of comprehensive error prevention of CYG Contron in large petrochemical projects.