與用戶儀表交互測量和控制信號是用戶自動化策略的核心。橫河電機支持各種Fieldbus技術(shù)，包括傳統(tǒng)的4～20 mA、有線數(shù)字網(wǎng)絡(luò)和無線ISA100.11a標(biāo)準(zhǔn)。這些技術(shù)可根據(jù)用戶需求應(yīng)用于設(shè)備、主機和解決方案層級。

通過橫河電機易于連接的網(wǎng)絡(luò)轉(zhuǎn)換器，能夠?qū)S485設(shè)備或模擬信號與DeviceNet通信PLC相連。

橫河電機提供一系列通信協(xié)議，包括FOUNDATION現(xiàn)場總線、HART、BRAIN、ISA100、Profibus和Modbus等，用于支持不斷發(fā)展的數(shù)字通信技術(shù)中的智能設(shè)備。

Here s how Shell upgraded from a pneumatic instrumented plant to a fully digital control system.

Decades of operation, modernization and expansion have left many chemical plants with a somewhat haphazard automation mix of different controls, process control systems, remote I/Os and field devices. The various components may use different communication protocols such as HART, PROFIBUS or FOUNDATION Fieldbus, and are often based on different device integration technologies. 

The changes in social environment, such as globalization of enterprise activities, depletion of natural resources, and eco-oriented movement will affect the structure of mass production. Control systems must be prepared with flexibility and scalability in both size and function to adjust to the changes.

To configure a compact, low-power medium attachment unit for field buses, i.e., a fieldbus MAU, an IC comprising a power generator, transmitter/receiver and other functions is needed. While we at Yokogawa had already developed a fieldbus MAU IC, we have now developed another MAU IC that includes large-scale design changes made mainly to comply with the low-power signaling requirements of the fieldbus specifications. 

Progress in digital signal processing and network technologies has enabled advanced functions which cannot be achieved by traditional field devices with 4-20 mA signal, to be implemented on field devices. Standardization of international fieldbus specifications, notably the FOUNDATION Fieldbus, has enabled users to build optimum field networks comprised of freely chosen field devices from various device vendors.