How quickly should the compressor build from 50 to 90 psi when testing the supply circuit?

When testing the supply circuit of an air brake system, the compressor should ideally build pressure from 50 to 90 psi within a specific timeframe to ensure its efficiency and proper functioning. The correct timeframe of 3 minutes for this pressure build-up is based on industry standards that ensure the compressor is operating effectively.

A time of 3 minutes provides a balance between ensuring the compressor can build pressure quickly and allowing for realistic operational conditions. If the pressure takes longer than this, it could indicate a potential problem with the compressor or leaks in the system. This timeframe is useful for identifying issues in the air brake system that could affect the safety and performance of the vehicle, as slow buildup may suggest mechanical failures.

On the other hand, shorter timings may not allow enough opportunity to observe the performance under load conditions, while longer intervals might indicate inefficiencies or issues that could compromise the safety and effectiveness of the braking system.