Devicenet is an open, low-cost, high-performance communication Network based on CAN (Controller Area Network) technology developed in the mid-1990s, which meets global industry standards and was originally developed and applied by Rockwell Company in the United States.

Many features of Devicenet are inherited from CAN, a well-designed communication bus, which is mainly used for real-time transmission of control data. The main features of DeviceNet are: short frame transmission, the maximum data of each frame is 8 bytes; Non-destructive bit-by-bit arbitration technology; The network can connect up to 64 nodes; The data transmission baud rate is 125kb/s, 250kb/s, 500kb/s. Point-to-point, multi-master or master/slave communication mode; Physical and data link layer protocols of CAN are adopted.

Six, HART bus

HART, High Speed Channel protocol for addressable remote sensors. In the 1980s, HART came into being because most meter users wanted a digital communication standard compatible with 4 to 20mA analog signals. This standard was introduced in 1986 by Emerson’s Rossmond.

369-HI-R-M-0-0-0-E

369-HI-R-M-0-0-0-E

HART protocol uses FSK frequency shift keying signal based on Bell202 standard to superposition 0.5mA audio digital signal on low frequency 4-20mA analog signal for two-way digital communication, and the data transmission rate is 1.2kbps. Since the average value of the FSK signal is 0, the size of the analog signal transmitted to the control system is not affected, and the compatibility with the existing analog system is guaranteed. In HART communication, the main variables and control information are transmitted by 4-20mA, and additional measurement, process parameters, equipment configuration, calibration, and diagnostic information are accessed through HART if needed.

7. CClink

CC-Link is the control and communication link system, which is jointly launched by a number of companies led by Mitsubishi, is an open fieldbus, its data capacity is large, the communication speed is multi-level optional, and it is a composite, open, adaptable network system, which can adapt to the different ranges of higher management network to lower sensor layer network.

Viii. WorldFIP

WorldFIP is one of the three components of the European standard EN50170 (Volume3), which is developed by adopting the IEC International Standard for Physical Layer (1158-2) on the basis of the French standard FIP-C46-601/C46-607. It consists of three communication layers. The distinctive feature of WorldFIP is that it provides a single fieldbus with a physical layer for all industrial and process control. The underlying control system, manufacturing system and drive system can be directly connected to the WorldFIP bus at the control level, without the need to mix RS485 and other low-speed buses to connect to the underlying equipment to achieve the same function.