BUILDING DEVICES CONTROL SYSTEM BASED ON ETHERNET AND CAN AND ITS APPLICATION IN LIGHTING SCENE PROJECT

The feature of building devices control system can be described as multi-point, exact demands of synchronization and real-time control, dynamic connections among the control points and so on. Aim at it, this paper presents a complex control system based on Ethernet and CAN (Control Area Network). Hardware and software of the field-controllers, area-controllers and control center are designed in the paper. In CAN Field-bus, field-controllers are in charge of receiving instructions from the host computer, showing real-time control effect, obtaining fault information of lighting devices and sending it to the host computer. Area-controllers realize the conversion between the data transmission protocol of Ethernet and that of CAN Field-bus. Meanwhile, it makes the data transmission between host computer and field-controllers transparent. The host computer will calculate the matrixes in control instructions, send them to the field-controllers, change the control strategy according to the fault information from field-controllers and send the alarm signal out as well. The whole system is designed as a modularization configuration, flexible, easy to be integrated and extended. Alarm function is introduced into the control system, in which the alarm message is transmitted by GSM wireless network. It can also receive remote wireless control instructions. The project has been applied into a 29-story building's lighting scene project successfully.