Characteristics and Advantages of Fieldbus

Characteristics of Fieldbus

Fieldbus system breaks the structure of traditional control system and has the following characteristics in technology:

(1) The open fieldbus of the system is committed to establishing a unified open system of the factory bottom network. Users can form an open interconnection system of random size with products from different manufacturers through field bus according to their own needs.

(2) Interoperability refers to the realization of information transmission and communication between interconnected devices and systems; The interoperability means that the equipment of different manufacturers with similar performance can be replaced with each other.

(3) Intelligentization and functional autonomy of field equipment It disperses the functions of sensing measurement, compensation calculation, engineering quantity processing and control to the field equipment to complete the basic functions of automatic control, and can diagnose the operating state of the equipment at any time.

(4) The highly decentralized field bus of the system structure constitutes a new architecture of fully distributed control system, fundamentally changing the DCS system combining centralization and decentralization, simplifying the system structure and improving the reliability.

(5) Adaptability to the field environment Fieldbus is specially designed for the field environment, supports various communication media, has strong anti-interference capability, can use two-wire system to achieve power supply and communication, and can meet the intrinsically safe explosion-proof requirements.

Advantages of Fieldbus

Due to the simplification of the field bus system structure, the control system has shown its advantages from design, installation, operation to normal production and maintenance. The advantages of fieldbus are as follows:

(1) Save the quantity and investment of hardware. Because intelligent devices scattered on the site can directly perform a variety of sensing, measurement, control, alarm and calculation functions, the number of transmitters can be reduced, and there is no need for separate regulators, computing units, etc., no need for signal conditioning, conversion, isolation and other functional units of the DCS system and their complex wiring. Industrial control PCs can also be used as operating stations, thus saving a large amount of hardware investment, It can also reduce the floor area of the control room.

(2) The wiring of the fieldbus system to save installation costs is very simple. A pair of twisted pairs or a cable can usually be connected to multiple devices, so the consumption of cables, terminals, boxes, and bridges is greatly reduced, and the workload of wiring design and connector calibration is also greatly reduced. When it is necessary to add field control equipment, it is not necessary to add new cables, but can be connected to the original cables nearby, which not only saves investment, but also reduces the workload of design and installation. According to the calculation data of typical test projects, the installation cost can be saved by more than 60%.

(3) Maintenance cost saving The field control equipment has the ability of self diagnosis and simple fault handling, and sends the relevant diagnosis and maintenance information to the control room through digital communication. Users can query the operation of all equipment and diagnose the maintenance information, so as to early analyze the cause of the fault and quickly eliminate it, reducing the maintenance downtime. At the same time, the maintenance workload is reduced due to the simplified system structure and simple connection.

(4) Users have a high degree of system integration initiative. Users can freely choose the equipment provided by different manufacturers to integrate the system. Avoid limiting the selection range of equipment due to the selection of products of a certain brand, and do not be at a loss for incompatible protocols and interfaces in system integration, so that the initiative in the process of system integration is firmly in the hands of users.

(5) The accuracy and reliability of the system are improved. The field equipment is intelligent and digital. Compared with analog signals, the accuracy of measurement and control is fundamentally improved, and the transmission error is reduced. The simplified system structure reduces the number of equipment and connections, strengthens the internal functions of field equipment, reduces the round-trip transmission of signals, and improves the working reliability of the system.

In addition, because of its standardized equipment and modular functions, it also has the advantages of simple design and easy reconfiguration.