What is one purpose of the flow switch in the Type 3 system?

The flow switch in a Type 3 system serves the critical function of ensuring that the fueling process is safe and efficient. When the flow switch "locks on" the fueling pump, it indicates that the flow of fuel has reached a predetermined level, effectively signaling that the system is operating properly. By locking on the pump, the flow switch ensures that the fueling operation can proceed without interruption, as it provides a safeguard against conditions where there might be inadequate flow, which could lead to potential issues such as fuel spillage or system overload. This functionality is vital in maintaining the integrity of the fueling system and ensuring that it operates within safe parameters.