Design Of Multi-function CAN Bus Elevator Digital Intercom And Monitoring System

In recent years, many accidents about elevator had been happening frequently, including the world’s first elevator brand Otis Elevator and many big famous elevator companies. This gradually highlights the elevator safety problems. In order to guarantee the safe operation of elevators, elevator manufacturers begin to pay attention to the problem of elevator control, for the elevator to install monitoring equipment. Because the existing intercom system has been connected with the monitoring room, so it is best to combine the elevator control with intercom system, forming a unity, and it will be more effective to manage elevators.In view of the existing intercom system, the elevator intercom and monitoring system is designed by adding the elevator monitoring system based on the original elevator intercom through the CAN bus. It will be composed of communication network by the CAN bus, and used for each elevator equipment operation, fault, functional status and real time signal control and monitoring, so it can be communicated through the intercom system. The CAN bus is used for non-destructive bus arbitration technique to solve the problem of information conflict on the bus. When the signal of elevator monitoring system conflicts with the talkback control signal, the low priority signal will wait for the high priority to execution, so the whole system’s reliability and stability are security. At the same time the riding personnel safety and elevator equipment can be given a reliable guarantee. This design includes:Elevator intercom system:The system uses CAN bus combining with microcontroller to realize the system communication, system control and alarm linkage; and it uses I2C serial memory chip to realize the system register storage. Because CAN bus has many advantages, such as the strong real time data communication, simple structure, multi master communication mode and strong reliability in the implementation, signals can be transferred to workstations by CAN bus to realize the stability of communication that will is not influenced.Elevator monitoring system:the design of CAN Bus elevator control system network, including the interface and the terminal application, realization of the functions and so on, can timely and accurately send the state information of elevator running in the process to the monitoring system, then the information will displayed in the monitoring terminal host. When the monitoring network interfaces are insufficient, the network can be optimally designed through the addition of relay terminal.Host monitoring system sends request to lower position machine every once in a while about upload data to the epigenous machine. After lower position machine confirms the construction, epigenous machine timely displays the data. When the intercom is calling, calling signal transfer through CAN bus. The speech signal transfers in audio line alone. After testing, the elevator intercom and monitoring system of communication is normal, without the phenomenon of missing data, real-time display elevator status on the monitor computer, and clear communication.After testing, the elevator intercom and monitoring system of elevator are normal communication, and various state signal can be displayed on the monitor software in real time. It realized data query, statistics and other functions, without any data loss phenomenon. After the simulation of elevator repair and alarm state, the intercom sound clear, and without any interference to the monitoring system.