Which pressure setting initiates the back-up of HP air in LPA systems?

The correct pressure setting that initiates the backup of high-pressure (HP) air in Low Pressure Air (LPA) systems is 80 +/- psig. This pressure range is critical for ensuring that the LPA system operates effectively and has sufficient backup support when needed.

In many engineering systems, particularly in naval applications, having a reliable source of HP air is crucial for various functions, such as starting engines, operating pneumatic tools, and maintaining specific system pressures. When the LPA system pressure drops to around 80 psig, it triggers the backup system to engage, ensuring that there is always a reserve of high-pressure air available to maintain system integrity and functionality.

This mechanism is designed to prevent the complete depletion of high-pressure air, which could lead to system failures. It serves as a safety threshold, enabling the transition to backup air supplies before critical operations are compromised. The other pressure settings do not serve as the defined trigger for initiating backup in the LPA systems.