At what pressure in psi does the pantograph pressure control valve relieve excess pressure during refueling?

The pantograph pressure control valve is designed to maintain proper fueling pressure during the refueling process. When the pressure exceeds a specified limit, the valve opens to relieve excess pressure, ensuring safety and preventing damage to the fueling system. The correct answer indicates that the relief valve activates at a pressure of 75 psi. This setting is specifically designed to protect the integrity of the system and maintain optimal operating conditions for refueling.

Other pressures listed, such as 45, 55, and 65 psi, do not accurately represent the operational threshold for this particular valve. Each of those options is set lower than the threshold for the pantograph system, which can lead to inadequate pressure management and potential risks during refueling operations. Therefore, 75 psi is the optimal and safe setting for effective management of excess pressure during the refueling process.