(1) The functions of intelligent engineering building have the following characteristics: providing a safe, healthy, comfortable and effective working environment. It has strong flexibility, and can have different flexibility in design to meet different requirements of customers. Save the demand for regular operation and maintenance. It can meet the needs of future development.

(2) Consideration of intelligent building design: the field controller itself should integrate all functions. Once the system is out of control or network problems occur, the field controller can still ensure operation and improve the reliability of the whole system. The modular hardware design can effectively distribute the intelligent engineering system equipment throughout the building, and each equipment has a certain adaptability to meet the requirements of the environment, so as to give full play to the maximum control ability of each equipment. The system design shall be open. It can cooperate with various software and hardware interface standards in the market to minimize the obstacles of information exchange between systems. The system design shall be user-oriented, make it easy for users to operate and maintain, minimize the operation cost and minimize the time to repair the system failure.

(3) . weak current system structure of Intelligent Building: the weak current system of intelligent engineering building generally includes the following subsystems: building automation management subsystem (BAS), automatic fire alarm subsystem (FAS), security monitoring subsystem (CCTV), satellite receiving and cable television subsystem (CATV), underground garage management subsystem (CPS), public address and emergency broadcast subsystem (PAS) Program controlled exchange subsystem (PABX) and structured generic cabling system (PDS) often include entrance and exit control subsystem and anti-theft alarm subsystem in building automation management subsystem. Each subsystem of the intelligent building provides the monitoring and management of various electromechanical equipment for the building, creates a safe, healthy, comfortable and pleasant office environment for building users, provides modern communication means and office conditions, and meets the requirements of various users for different environments and functions.

2. Each subsystem of weak current system of intelligent building
(1) . building automation management subsystem (BAS) Building automation management subsystem is the core of the weak current system of intelligent building, and its high reliability is the cornerstone of the high reliability of the whole weak current system. Therefore, BAS system adopts three-level control mode. The operation station level is composed of computer and printer, and adopts real-time graphic monitoring operation software. It is the man-machine interface of BAS system, which can observe the current situation by displaying or printing various information Or the previous system and the operation status and data of various electromechanical equipment monitored by it, and the operation of various electromechanical equipment can be changed through the operation of keyboard or mouse, so as to meet the specific monitoring requirements.

(2) . network controller level
Network controller is not only an important device of BAS system communication network, but also the heart of the whole BAS system. On the one hand, it communicates with operation station and other network controllers through Ethernet, on the other hand, it communicates with direct digital controllers distributed throughout the building through fieldbus network. All information of the whole system is stored in the network controller, and the network controller has a variety of control functions Yes, such as operation time statistics of various electromechanical equipment, event statistics, peak shaving and load limiting calculation of power load, linkage control, unit group control and other complex high-performance control functions, which can orderly monitor the whole BAS system. At the same time, the network controller is an important interface for connecting each subsystem to the BAS system for facility integration.

(3) . field controller level
The field controller constitutes the third level of the system. Its main function is to receive the data sent by various sensors and detectors installed on various electromechanical equipment, and carry out corresponding operations (such as PID, maximum value, delay, etc.) according to the preset parameters and pre-prepared control program in the controller And control all kinds of electromechanical equipment, and adjust parameters or start relevant programs at any time according to various instructions sent by the operation station through the network controller to change or start the monitoring of corresponding equipment.22