303.02.0097 KNORR-BREMSE 4-circuit protection valve

The brake system relies heavily on precise pressure regulation to ensure safety and reliability during operation. This 4-circuit protection valve is engineered to provide stable pneumatic control across multiple circuits, maintaining high-strength performance in demanding heavy commercial vehicle environments.

This specific component is an OE equivalent for the KNORR-BREMSE AE4447. The 303.02.0097 is designed for compatibility with KNORR-BREMSE systems, ensuring seamless integration within the pneumatic circuit. The technical specifications include a primary port of M22x1,5 and four secondary ports (21, 22, 23, 24) with M16x1,5 threading. The opening pressures are calibrated at 6,9 BAR for circuits 21, 22, and 24, while circuit 23 operates at a 7 BAR threshold. The 303.02.0097 is the OE equivalent of the KNORR-BREMSE AE4447 used in professional braking systems.

For workshop technicians and fleet managers, installation requires precise alignment of the M16x1,5 ports to prevent pneumatic leaks. Regular inspections of the opening and closing pressure thresholds—specifically the 4,5 BAR closing pressure across circuits—are recommended to ensure optimal system response and prevent pressure drops during heavy-duty service.

Maintaining the integrity of the pneumatic control system is vital for long-term vehicle safety. Using high-grade components like this protection valve helps prevent unintended pressure fluctuations in the braking architecture.