The function of soft start valve is to build up pneumatic system in safety and protection. Please input air supply to P port on soft start valve, when the coil on soft start valve is energized, soft start valve is open and a little air controlled by internal throttle valve output from A port to make air pressure increase slowly in pneumatic system. While output pressure is equal to 50% of input pressure, soft start valve is fully open in highest flow rate. When the coil on soft start valve is de-energized, P port is closed and the air return to R port through internal check valve for exhaust, the pressure in the system is down to zero to protect whole system in safety.
