Research and design of automatic control system for central air conditioning in building automatic network system

Automatic control system for buildings consists of many subsystems such as, heating and ventilation, fire protection, elevator, cold/hot water supply, Security and access control, power distribution and monitoring, parking management etc. In the paper, the water circulating subsystem and air conditioning units monitoring and control subsystem are treated as a central air-conditioning automatic control system, and ultimately, in accordance with MODBUS RTU or Profibus protocol, are integrated into the overall building automation system to solve the network communication problems in the building automation network due to the inconsistency of subsystem equipment by different manufacturers.