Built-in two sets of passive relay contact output, can directly control the solenoid valve and less than 1100W AC fan (AC220V). Remote detector sensitivity correction, zero adjustment, no need to use large valve equipment for on-site calibration. With automatic fault detection function, and can indicate the fault location and type; It can store 2000 historical records by category. Optional three-wire system transformation work; Communication ports are reserved for the system to facilitate networking with third-party control systems.