The HB-DT series is mainly used for installation inside the elevator. It usually broadcasts elevators for safe information, public welfare information, various notices, business advertisements, etc.; In case of emergency (such as when the elevator is running abnormally), it realizes emergency alarm, contact rescuers; use network connection (support wired, WIFI, 3G, 4G and other connection methods) to achieve unified management and release of equipment and programs. It can also use the sensor data of the terminal to collect elevator related operational data, and perform abnormal state through microprocess or data analysis, comprehensive processing by the server to achieve elevator failure alarm, sleepy rescue, daily management, quality assessment, hidden danger prevention and other functions.