Up to 128× can be connected using AC220V power supply; The 4-channel module provides DC24V power supply to the connected sensors and receives and displays the working status of the monitored fire equipment power supply through a two bus system. When a fault occurs, it emits an audible and visual alarm signal to monitor the open circuit and short circuit between the connected sensors and module circuits. It can also monitor the working status of its own power supply and perform self inspection on local devices. It has the function of printing fault information and can save 1000 fault records. The 5-inch color LCD screen displays in Chinese and is operated on a touch screen. It is easy to use and has CAN, RS485, 10/100M network port networking interfaces that can be connected to backup power supply. In the event of a main power failure, it can continue to operate for 8 hours with effective communication distance; 3000m