Fieldbus Wars continue

One of these savings involves maintenance costs. “A major oil company performed an internal study on conventional 4-20 mA installations and learned that approximately 60% of the times that maintenance personnel went into the field to check an instrument, the trip was unnecessary,” Barbour notes. “The return on investment can be measured in the short term from installation/commissioning savings, and continues through long-term savings resulting from proactive maintenance and fieldbus monitoring capabilities.”

Rockwell Automation agrees: “Over time, user adoption of ‘smart instruments’ (See Figure 2 below) in process applications will continue to increase as the tools required to configure, calibrate, monitor, and manage these devices also evolve,” says Dave Appleby, product marketing manager at Rockwell Automation. The company also believes that the value in smart instruments lies in the data they’re able to provide, rather than in the way users connect to them.

FIGURE 2: DEVICENET STEPS UP
A DeviceNet-based fieldbus system controls operations at Rhode Island Beverage’s bottling plant in Warwick, RI. Source: Rhode Island Beverage

For this reason, Rockwell expects skyrocketing sales of networks based on the Common Industrial Protocol (CIP). “Rockwell Automation supports a range of open, CIP-based networks, primarily those based on Foundation fieldbus, EtherNet/IP, ControlNet and DeviceNet," says Doug McEldowney, Rockwell’s strategic marketing manager. ODVA is the supporting organization for CIP-based networks, and it consists of members from automation companies including Rockwell, Cisco, Omron, Eaton, Sick AG, and Numatics.

As you might expect, Siemens likewise sees increased Profibus sales. “Over the past five years, Siemens has seen a steady growth rate in our Profibus components sales,” says Moin Shaikh, Profibus marketing manager at Siemens. “A number of our customers are now employing Profibus in large process control applications and in mission-critical applications. Many of these customers tell us they’re seeing short payback times of their fieldbus installations.”

Meanwhile, Honeywell is riding the fence. “From Honeywell's vantage point, we’re seeing a significant upsurge in major process automation projects implementing fieldbus technology, specifically Foundation fieldbus, HART and Profibus DP,” says Tim Sweet, product marketing manager for Experion PKS at Honeywell Process Solutions. “Use of these technologies has soared in the past three years. Before that, people seemed to be experimenting. These technologies are now readily accepted and readily deployed. We think these fieldbus protocols are here to stay and are adding significant value to the adopters.”

Jane Lansing, PlantWeb marketing vice president for Emerson Process Management agrees: “When we first introduced fieldbus, almost all the fieldbus projects were ‘science projects.’ Users wanted to trial and test the robustness of the technology in non-critical applications,” she says. “This lasted a couple of years. Then we started seeing customers buy their second and third system, which were still small and non-critical. It wasn’t until 2001 that the first major, grassroots, fieldbus-specified project started up.

“Today, most major projects in the world specify Foundation fieldbus. Fieldbus is controlling mission-critical applications in all major industries, particularly in hydrocarbons. Emerson is seeing very strong double-digit growth in fieldbus. This has happened in just 10 years, which is a short adoption time in process control. The one thing that our industry surprises us vendors with, over and over again, is slow adoption.”

	FIGURE 3: ETHERNET LUMBERS ALONG
	This control system for a planer/sorter at a lumber mill has an Ethernet-based fieldbus (blue wires) and A-B PLCs. Source: Concept Systems

Randy Bradford, systems engineer at Concept Systems, a systems integrator in Albany, Ore., has been developing Ethernet (See Figure 3) and Foundation fieldbus applications since 1998. “At first, Foundation fieldbus seemed like a solution looking for a problem, but as the performance of instruments improved, and as the calibration support over the bus has improved, it has become more useful in a wider range of applications,” says Bradford. “There are multiple vendors supporting the more popular open standards, such as Profibus and Foundation fieldbus. Sometimes, the instruments produced by the inventors of the bus technology work better than those of other vendors providing compatible devices. For example, it’s our experience that Foundation fieldbus instruments provided by Emerson work better.”