Process Control and Wireless Networks

Industrial plants, factories and process automation systems are increasingly deploying information and communications technologies to facilitate data sharing and analysis in integrated control networks. Despite the harsh process control environment, signal propagation loss and radio frequency (RF) interference, wireless connections provide fast and easy access to a variety of field instruments and reduce network installation costs and ongoing maintenance outlays. This serves as an incentive for the adoption of industrial wireless networks based on industry standards such as ISA100.11a, a wireless networking technology standard developed by the ISA (International Society of Automation) and the WirelessHART, a wireless sensor networking technology based on the Highway Addressable Remote Transducer Protocol (known as HART). Wide-scale adoption proceeds cautiously though, as industrial environments vary widely and process control systems exhibit a multitude of critical wireless networking requirements, such as:

• Deterministic transmissions in shared wireless bandwidth.
• Low-cost operation.
• Long-term durability.
• High reliability in the harsh radio propagation environment.

Wired connections have proven themselves effective in supporting reliable, point-to-point communications between the controller and the field instruments. A problematic limitation exists with wired connections though - they are unable to accommodate the growing demands and future requirements to support adaptive network topology and rapid reconfiguration encountered in new process control systems.

In lieu of laying down miles of cables to connect hundreds of field instruments, industrial wireless communication networks provide wireless connections with customized network topology, allow for plug-and-play configuration, and offer lower installation and maintenance costs.

Compared with the requirements of standard Internet data services, wireless in the process control environment has stricter quality of service (QoS) requirements. These include more highly reliable transmissions in mobile use cases as well as centralized data analytics, tighter message latency, and lower power consumption.

Hazardous Area Antennas

Gathering information in hazardous areas is critically important for plants to access. Wireless communications is vital for improved efficiencies, real-time monitoring of machinery and equipment, and the safety and well-being of personnel.

Hazardous area antennas from Analynk Wireless are designed and constructed for very rugged industrial applications. Furthermore, all Analynk hazardous area antennas  are UL  listed for Class 1, Groups C & D and have ATEX/IECEx Certification. Finally, a range of frequencies are available from 900MHz, 2.4GHz, Cellular, GPS, Iridium and dual bands.

Adapting Wireless Access Points to Hazardous Areas

Cisco 3602E and Hazardous Enclosure

Wireless technologies are not new in industrial process control, and are increasingly used for real-time control and critical applications. One key piece of hardware is the wireless access point (AP). Wireless access points are networking devices that allows a Wi-Fi device to connect to a wired network.

In autonomous architectures, standalone wireless access points are used to implement all WLAN (wireless local area network) functions. They  have to be configured and managed individually and are typically used in smaller installations or stand-alone applications.

Aruba-AP70 and Hazardous Enclosure

Unified architecture (UA) is preferred in large-scale, plant-wide wireless deployments because of its ability to handle a variety of clients and applications. Unified architecture offers guest systems, intrusion protection and facilitates plant-wide mobility. Centralized control and easy configuration are delivered through light-weight access points (LWAP) and wireless LAN controllers (WLC).

Well Known Manufacturers of Access Points

Meru AP-1020e and Hazardous Enclosure

Cisco Systems, Inc. develops, manufactures and sells networking hardware, and telecommunications equipment. Cisco specializes into specific tech markets, such as Internet of Things (IoT), domain security and energy management.

Miraki MR72 and Hazardous Enclosure

Aruba, a Hewlett Packard Enterprise Company, brings Wi-Fi wireless LAN mobility solutions to enterprise networks. Its core products are wireless Access Points (APs), wired switches, mobility controllers, and network management software.

Meru Networks is a supplier of wireless local area networks (WLANs) to healthcare, enterprise, hospitality, K-12 education, higher education, and other markets.

Zebra-AP7532 and Hazardous Enclosure

Meraki was acquired by Cisco Systems in December 2012 and is an equipment and tech company who's solutions include wireless, switching, security, EMM, communications, and security cameras, all centrally managed from the web.

Zebra Technologies/Motorola manufactures computer systems that include printing, barcode, communication, mobile computing and advanced data capture communications technologies to the manufacturing supply chain, retail, healthcare and government sectors.

Adapting Access Points for Hazardous Area Use

In industrial facilities, hazardous areas are defined as areas where flammable liquids, gases, vapors or combustible dusts exist in sufficient concentration to produce an explosion or fire. In order to locate access points in hazardous areas, specialized access point enclosures fitted with explosion-proof antennae must be used. These enclosures provide UL listed, Class 1, Division 1, Groups C &; D, Zone 1, ATEX Zone 1 antennas (2.4GHz and 5.0GHz), mountings brackets and hardware.

Analynk, a manufacturer of wireless instrumentation in Columbus, OH, offers a wide variety of hazardous area access point enclosures as well as explosion-proof antennas.  Contact them by visiting https://analynk.com or calling 614-755-5091.