These communication protocols are commonly used in building automation systems.

With the development of information technology and the entire information industry, building automation is also moving towards integration, intelligence and networking. The basis of large-scale system integration is the communication network, and its technical core reflects system integration and related communication protocols.

To ensure the normal transmission of information, there must be a set of conventions or rules regarding the order of information transmission, information format and information content. This set of conventions or rules is the network protocol. Simply put, the network protocol seems to use the language when communicating between devices.

Different communication protocol standards and performance differences, inter-system communication compatibility and interchangeability issues, need a unified open standard to achieve compatibility and exchange of products. The advantage of this is that all manufacturers' instruments and systems can communicate with each other, so that each manufacturer's products are not restricted by proprietary protocols, which brings convenience to users.

The main advantages are: reduce wiring, installation and other costs; save operating and maintenance costs; high digital transmission accuracy; enhance system flexibility and upgrade convenience. At present, international network standards and protocols are developing rapidly and are constantly changing.

At present, most LAN, backbone and Internet interconnection technologies have matured and are widely used. There are many building system equipments and control networks. Each manufacturer provides building equipment and control systems. The communication protocols are different, resulting in poor interoperability between different manufacturers' equipments and affecting system management, maintenance and safety.

For a long time, users have been hoping to break the monopoly of building control manufacturers and are eager to adopt standard communication protocols. People have already seen that one does not have the openness and can not realize the mutual operating system, which will bring inconvenience to the system operation and maintenance, upgrade and transformation. In this form, standard protocols such as LonWorks and BACnet, as well as KNX, have emerged and have formed the current mainstream communication protocols.

LonWorks

Launched in 1993, LonWorks is unified, open and interoperable. The LonWorks fieldbus network is referred to as the LON network. Its core is the Neuron chip. It can manage communication, and has input and output functions. The chip contains three CPUs to manage network, media access and applications.

LonWorks neural network technology is a fieldbus technology widely used in building automation systems in recent years. It is characterized in that each control node on the LON bus is equipped with a neuron control chip, and each chip is equipped with Standard network communication protocol, which enables various devices connected to the LON bus to communicate with each other, and realizes the integration of building automation systems. It has been widely concerned and widely accepted in the field of automatic control in a short period of time, and has become the field of building automation control. General standard.

It can be said that the application field of LonWorks technology is building automation. It includes all areas of building monitoring systems, namely population control, elevator and energy management, fire protection, lifesaving, heating and ventilation, measurement, security and so on.

In the construction industry, the medium access control layer of the LonWorks protocol, namely the seventh layer protocol and the second layer protocol, has been accepted by ASHRAE as the building automation control network (BACnet) standard and also adopted by the American National Standards Institute (ANSI). .

BACnet

BACnet is the abbreviation of A Data Communication Protocol for Building Automation and Control Networks. In 1987, the Standards Committee of the American Society of Heating, Ventilating and Air-Conditioning Engineers (ASHARE) mobilized more than 20 industry experts from around the world. After eight and a half years, in 1995. In June, ASHARE officially passed the building automation industry communication standard - BACnet, the standard number is ANSI/ASHAREStandard 135-1995, became the American national standard in December of the same year, and was also recognized by the European Commission and became the draft EU standard.

KNX

In the early 1990s, Europe's three residential and building control bus protocols EIB, BatiBus and EHS explored the market and standardization in their respective markets. Although they have achieved success in different regions and different fields, the prospects are still unpredictable.

Later, the three organizations decided to join forces to develop the smart home and building market. They established the Konnex Association in 1995 and launched the KNX standard in the spring of 2002. KNX (short for Konnex) is an officially approved open international standard for residential and building control.

The standard is based on EIB, taking into account the physical layer specifications of BatiBus and EHSA, and absorbing the advantages of BatiBus and EHSA configuration modes, ultimately providing a complete solution for home and building automation.