System components of industrial enterprise networks must be built to operate in harsh conditions and extreme environments, and must also support standard communication protocols. In some circumstances, these networks also need to resist exposure to electric shock, vibration and physical abuse. Most industrial enterprise networks are required to perform normally and accomplish their designed functions under high temperatures, or in bad weather and other harsh conditions.
To ensure device interoperability, industrial enterprise networking solutions must support protocol models such as ISO/OSI, TCP, IP, Ethernet, Fieldbus, Modbus, HART, RTU and so on. To access the networked devices across the Internet, a built-in web server is needed to allow remote access and management of the attached equipment using a standard web browser. Multiple serial devices can also be cascaded from a single network backbone connection, eliminating the need for expensive switches, hubs, routers, bus, and cables.
Industrial enterprise networking solutions connect enterprise systems to the factory floor and workshop devices without disturbing control networks or needing dedicated wiring for remote working. An industrial networking solution should therefore enable connection of virtually any piece of factory equipment to a network or to the Internet access, management, control, and repair, and even automatic data capture.
Such a network will also allow engineers and managers to leverage their existing network wiring and corporate IP networks. To collect information from this network, it must be able to be used directly with two systems typically found in most industrial operations: a human machine interface (HMI) and a supervisory control and data acquisition (SCADA) system.
In the past decades, enterprises have enabled remote monitoring and managing in real time by placing their equipment on an existing local area network (LAN). Indeed, LAN networking provides a solution which satisfies all the requirements of industrial enterprise networks. Therefore, LAN has become a dedicated architecture for implementing industrial enterprise networks. The following are two examples of the applications of LAN for industrial enterprise networks.
(a) Industrial enterprise networking example: Rockwell Automation
Rockwell Automation is one of the leading global providers of industrial automation power, control,and information solutions that help customers meet their manufacturing objectives. One of the company’s leading brands is Allen-Bradley, a manufacturer of automation controls and a provider of engineering services. Allen-Bradley control solutions have set a high standard in industrial automation, helping the industry apply programmable logic controller (PLC) technology over the past decades.
Rockwell’s customers needed to remotely access and manage their PLCs when only a serial interface was available. To meet their needs, Rockwell designed an industrial device networking server to provide Ethernet/IP connectivity. Their server provided a gateway from their controllers’ serial port to an Ethernet network. This allowed their customers to upload and download programs, communicate between controllers, and generate email messages via SMTP (simple mail transport protocol). Rockwell Automation has enhanced the capabilities of their PLCs and allowed their customers to remotely access their controllers from anywhere in the world.
(b) Industrial enterprise networking example: Texas Instruments
Texas Instruments is one of the world leaders in digital signal processing and analog technologies that drive semiconductor engines. This company needed secure remote access to all its process control equipment at the company’s support center, while keeping costs and wiring to a minimum. The company needed to measure and read the concentration of contaminants in water samples. Before industrial enterprise networking was deployed, the process used was complex, involving the transfer of a signal from a water analyser to a PLC, and then to an HMI, where reading of the measurement was often flawed. While the company’s facility control center operated process control equipment on a legacy network, independent of their LAN, they needed to network-enable all of the process control equipment at the support center, which would have required 1,500 feet of wiring and conduit spanning multiple buildings for added expense and time.
By implementing industrial enterprise networking with a LAN solution on multiple key pieces of equipment such as airflow, water and gas detectors at its fabrication facility, its support center could remotely monitor and control critical elements of the fabrication plant (airflow, water treatment and gas detection) in an adjacent facility. By integrating the industrial device networking solution, all of its equipment in the support center is now Ethernet-enabled, allowing more than 500 PCs in the center to have access in real time to information as it is generated by the process control equipment. As a result, it is no longer necessary for a technician to patrol the floor of the plant to monitor each device individually and response time is significantly improved whenever a failure is detected.
These two examples demonstrate to some extent how industrial enterprise networks can revolutionize the world of industrial production and manufacturing. The adoption of industrial enterprise networking is increasing as local area network (LAN) or wide area network (WAN) architecture becomes more available. Since there seems to be no substantial difference between the LAN and the WAN for industrial automation and controls, this textbook uses LAN as a unified definition of LAN and WAN. LAN architecture has developed significantly over the past decades, generating two important forms of LAN; the virtual local area network (VLAN) and the wireless local area network (WLAN).
Virtual LANs (VLANs) have developed into an integral feature of the switched LAN solutions of every major LAN equipment vendor. Although end-user enthusiasm for VLAN implementation has yet to take off, most organizations have begun to look for vendors that have a well-articulated VLAN strategy, as well as VLAN functionality built into their products. One of the reasons for the attention is the rapid deployment of LAN switching that began in 1995.
Wireless technology has revolutionized how computer users access information. And this revo lution continues in the world of industry. Wireless device networking is the best alternative when it is impractical or cost-prohibitive to run cabling to connect factory equipment to a LAN or the Internet. Wireless connection reduces the need for expensive wiring, which can be upto two-thirds of the total cost of an installation in an industrial enterprise.
More info at szjawest.cn .