Cover Story – Wireless Applications: Less Cost, More Productivity, Compliance

What does industrial wireless do for you? There’s up to 90% installed cost savings. Look for productivity, security, and regulatory compliance advantages.

By Mark T. Hoske, Control Engineering June 22, 2011

Recent applications of industrial wireless technologies at Western Refining and Toyota Motor Manufacturing Kentucky show such benefits as up to 90% installed cost savings, and increases in productivity, safety, security, and regulatory compliance, for a very fast return on investment (ROI) opportunity.

Wireless-enabled industrial products, world shipments, are estimated to grow from 1.2 million in 2009 to over 3 million in 2015, a compound annual growth rate (CAGR) of 18%. IMS Research says:

  • Many users consider installing wireless very valuable
  • Many see ROI within a year
  • Future growth will be driven by new use cases for wireless (so look around)
  • After end users invest in wireless infrastructure, expanding into more applications becomes more attractive
  • Lack of standardization will become more important in future applications with a longer payback period.
  • End users have to be certain that they can source replacement parts for many years, if investment in these applications is to be attractive.

With results like this, implementing industrial wireless may have switched from ROI justification to more of an explanation of why you haven’t raked in these kinds of benefits yet. A wireless webcast explains more, along with additional tips and diagrams below regarding wireless and SCADA, and other benefits are linked at www.controleng.com/wireless. Reginald Joseph, Western Refining senior process controls engineer, told Control Engineering about the following benefits for process unit and tank operations.

Less wiring costs, more performance

At Western Refining’s Gallup, N.M., refinery, process unit and tank operations have been upgraded using an advanced wireless mesh network. Based on Western Refining’s experiences, wireless is a desirable alternative in applications where traditional copper wiring can increase cost, maintenance, and unreliability. With wireless, plant infrastructure investments are reduced and the return on investment (ROI) can be significant. Projects that previously could not occur have become worthwhile. As the only active refinery in the Four Corners region, Western’s Gallup facility primarily relies on a locally produced, high-quality crude feedstock known as “Four Corners Sweet.” This crude supply is supplemented with feedstock from outside the area.

Mountainous project

The operation is situated at nearly 7,000 ft elevation on rocky and mountainous terrain. Production processes and storage facilities cover a large geographical area, so instrumentation for monitoring the refinery’s remote offsite units can be very costly. An on-site survey determined the project scope and challenges, looking at the coverage area desired at the plant, existing power and network infrastructure, and implementation goals (immediate and long-term). It also assessed interfering and operating frequencies currently in use or ambient in the environment and identified any potential security exposures.

The Gallup refinery uses a legacy Honeywell TDC 3000 Distributed Control System (DCS). Management sought to extend monitoring capabilities to remote tank farm areas. The cost of traditional wiring and conduit for monitoring outside storage units was estimated at $15,000 to $22,000 per tank. Up to 90% of the installed cost of conventional measurement technology can be for cable conduit and related construction. With wireless field devices, wired infrastructure is largely unnecessary. Using industrial wireless solutions reduces process monitoring costs, allows connection to points that are physically or economically difficult to access, and permits easy expansion for additional measurement or actuation points for the cost of a transmitter. Security is robust, power management and multispeed monitoring are predictable, and Wi-Fi coverage is provided at no additional cost.

Wireless benefits

  • Industrial wireless technologies
  • Revolutionize process measurement
  • Offer new opportunities to optimize plant performance, reliability, and safety while reducing installation costs
  • Provide, with addition of wireless transmitters, an affordable and accurate alternative for applications involving supervisory control, monitoring, indication, and alarming
  • Can operate in the most demanding plant environments with recent advancements in radio technology and communications protocols
  • Bring self-healing wireless mesh networks to numerous industrial applications, beyond wireless-enabled versions of conventional field devices for process automation.

In 2008, the Gallup refinery began implementing a wireless solution that incorporates a multiprotocol, multistandard wireless network communicating simultaneously with Wi-Fi and industrial I/O devices. It also uses optional redundant synchronized gateways, which link the wireless network into the process control network (PCN). The wireless “backbone mesh” architecture incorporates field- and plant-level applications on one, unified network. The network uses externally powered multinodes scattered throughout the coverage area. The devices support industrial wireless standards for process control applications and provide sensor data transmission redundancy at all levels. Multinodes communicate with each other and provide a backhaul for bringing information to a gateway, where it passes into the larger wired PCN. The meshing action takes place between multinodes, not at the instruments. For safety, at least two multinodes receive data from each instrument, creating a redundant path.

Gateway, 38 instruments

The multifunctional wireless mesh network implemented at the Gallup refinery supports a variety of applications within one network. Wireless technology was first employed for tank gauging and is now being introduced for high-level analog and digital indications in the process units. Wireless monitoring data is integrated into the refinery’s existing DCS and advanced applications. Wireless transmitters have replaced outdated pneumatic devices used for valve positioning and process variable indication. An optimized wireless infrastructure with narrow band radio frequency hopping ensures maximum performance. Wireless devices transmit measurements to a base radio connected to the plant control system.

Western Refining’s current installation includes one wireless system gateway and four redundant multinodes connecting 38 wireless instruments. The wireless field devices send information to a series of multinodes, creating a mesh infrastructure that maximizes uptime and data security. At the Gallup refinery, wireless transmitters have broken down barriers to monitoring variables in areas where traditional hardwired transmitters were too costly, difficult, or time-consuming to implement. Instruments are designed for applications that are without access to power, are remote or difficult to access, require frequent changes in instrumentation schemes, or where manual readings are typically taken.

With wireless transmitters, engineers at the refinery can easily increase the number, frequency, and type of measurements. In addition, they can improve accuracy and consistency of measurement by replacing manual readings with automated online data collection. Online communication with the control system also helps ensure precise time tracking of information for use in troubleshooting process problems.

Project results

For Western Refining, wireless has proven to be a desirable alternative to traditional copper wiring, which increases cost, maintenance, and unreliability. ISA100 DSSS wireless transmitters can be used to monitor a variety of processes and assets in hazardous and remote areas, and this data can be used in a variety of systems. Wireless frequency-hopping spread spectrum technology also adds security and ensures that noise interference at any one frequency does not block communications or cause security concerns. One scalable wireless network conserves spectrum and power.

The wireless installation was fast, inexpensive, and easy, according to those involved. Operators, engineers, and technicians have one system to learn, operate, and maintain. Wireless allows plant personnel to react quickly to changing conditions and gather information they need to optimize processes. Plant infrastructure investments decrease immediately, and significant ROI can be realized. I/O costs have been significantly lowered, and projects that previously could not occur now become immediately worthwhile.

By 2011, Western Refining plans to install more than 100 wireless transmitters throughout the Gallup refinery for various process monitoring tasks, as well as noncritical control applications. Wireless instrumentation will be installed on at least six more process units. The first control-related wireless applications will be in offsite blending. At Western Refining, wireless applications have helped to optimize plant productivity and reliability, improve safety and security, and ensure regulatory compliance. More than just avoiding the cost of wire, the key value of wireless lies in the ability to integrate valuable data into existing control systems and advanced applications, while also sharing that data with other networked applications. Read more details and see more images about this application below.

Wireless monitoring, compliance

Next, Susan Schnelbach, technical content architect at Banner Engineering wireless product division, explained how wireless monitoring of detention pond levels helps Toyota Motor Manufacturing Kentucky comply with federal law and related regulatory requirements. Detention ponds are typically used to control the release of storm water runoff, especially if the runoff may contain contaminants from parking lots or building rooftops. Using a wireless monitoring system eliminates the need for someone to drive out to each pond to manually monitor the water levels.

With the passage of the 1972 Clean Water Act, the Environmental Protection Agency is responsible for regulating storm water runoff. The goal of this act was to restore the waters of the United States to a quality level that “provides for the protection and propagation of fish, shellfish, and wildlife and provides for recreation in and on the water.” The Water Quality Act of 1987 expanded water regulations to include industrial storm water runoff and required that states be responsible for issuing National Pollution Discharge Elimination System (NPDES) permits to large manufacturing facilities. Such facilities must then regulate all runoff that enters directly into any waters of the United States or to a municipal storm sewer system.

Toyota Motor Manufacturing Kentucky, a large automotive manufacturer located in Georgetown, Ky., has four such detention ponds located up to a mile away from each other. These detention ponds also are separated by several large buildings. The pond water must be tested after the first rainstorm of the month, and then the ponds’ drain gates are opened to allow the ponds to drain into local streams or creeks. At the end of the month the drain gates are closed until the next rainstorm occurs and the water is again tested prior to release. If it rains before the water has been tested for the month, Toyota’s employees must closely watch the pond levels until the water can be tested and released.

No line-of-sight needed

Because of the distance involved, and the location of several buildings between radios, Toyota Motor Manufacturing Kentucky collaborated with a vendor to decide to use radios that transmit data via multiple hops, back to a central location with a PC-based controller. Using the radios eliminated the need for line-of-sight between the ponds and the control location. The wireless networks are made up of one master radio and many repeater or slave radios. The networks are self-forming and self-healing networks constructed around hierarchical communication architecture.

As the wireless network is first formed, the master radio “searches” for any repeaters or slaves within range. Repeaters and slaves that are outside the master radio’s range search for other repeaters to “connect” to, automatically forming the most efficient wireless network possible while still maintaining a strong enough radio signal to reliably transmit the data. In addition to automatically forming complex radio networks, the networks can self-heal. If a radio loses synchronization to the wireless network, it may reconnect to the network using a different repeater radio.

For this detention pond monitoring application, submersible pressure sensors and a wireless radio with analog inputs were installed at each pond. Both devices were powered by a solar panel and backup battery pack. The pressure sensors were configured to sample the pond levels at five-minute intervals. The pond level data was transmitted back to the master radio, which was installed on the roof of a building and powered from the available 10 V dc to 30 V dc. All radios use a high-gain omni-directional antenna to ensure a reliable long-range communication network was formed in all directions. The master radio was connected to a host system that logged the pond level data and notified Toyota employees when the pond levels were rising.

Self-forming, self-healing radios

Four detention ponds have been successfully monitored using the radios. Toyota Motor Manufacturing Kentucky and the employees responsible for gathering pond level information eliminated the manual process for several detention ponds and ensure environmental compliance. Because the networks are self-forming and self-healing, long-range, they are easy to install and maintain. Before installing the wireless solution, monitoring detention pond levels required that someone drive out to each pond several times a day during storms.

Using sensors and a wireless solution eliminated the need for someone to manually collect the pond level data. The implementation gathers more information from each pond, allowing employees to more accurately track their runoff pond levels and prevent the accidental release of untested water. Read more details and see more images about this application below.

See more on:

Western Refining wireless application

Toyota wireless application

Other wireless applications and tutorials: www.controleng.com/wireless

Related networking webcasts: www.controleng.com/webcast

More on industrial networks: www.controleng.com/networks