The promise of wireless is clear: You can measure more in a plant situation, with new pieces of instrumentation checking different things and giving you more information (or at least data). But more than that, you can communicate easily with things that move: enterprise data on the plant floor, walk-around HMI, personnel locators, VoIP walkie-talkies, etc. The overall objectives of suppliers are similar, but the process of getting information to and from the plant floor is often what separates providers.

In my research on process plant wireless, one discussion I remember particularly was with Ian McPherson from Apprion. He said that manufacturers are pulled in one of three directions. They can design to:

• Maximize bandwidth;
• Maximize battery life (low power use); or,
• Maximize determinism (minimize latency).

No single technology does all three well. Thinking about that, I concluded those capabilities are mutually exclusive, but you might be able to satisfy two.

Emerson majors in battery life, minors in determinism. Key objectives: Easy deployment without wiring for instrumentation in a monitoring role.

Honeywell majors in determinism, minors in bandwidth. Key objectives: Deterministic instrumentation, suitable for control plus additional versatility.

Apprion majors in bandwidth, minors in determinism. Key objectives: Networking umbrella that supports a broad range of integrated applications.

OK, it’s an oversimplification, but not that far off. As you look at suppliers, you can discern their direction in the same way. Still, there is a convergence going on in the background. Much of it is still beyond the horizon, but all three are looking to the ultimate goal of an all-encompassing network from individual instrumentation to enterprise level. Some are working from the bottom up and some from the top down, but they are building.