Something in the air

Bob Gill, Group Editor

Ten years ago, if you saw a guy walking down the street in apparent animated conversation with himself, you might have thought him a possible escapee from the local psychiatric hospital or at least not in possession of all the right mental faculties.

But, of course, now it’s quite a common sight, and we all know that rather than insane mutterings, there is real conversation going on there and the other party could well be on the other side of the world.

Yes, the wonders of wireless. While we all maintain our fixed lines at home, it is our mobile phones that we are more attached to and which we use much more often – just check your two phone bills. Even that label, “fixed” has a somewhat negative connotation, implying something that is heavy, slow and immovable, while “mobile” is light, quick, anywhere, anytime.

So it’s not surprising that there is considerable excitement over the recent announcements concerning wireless instruments for process plants. Like mobile phones, the central proposition is the ability to do things that become possible once the constraints of wires are removed. Or as one vendor puts it, “No Wires. No Limits”.

In practical terms, what this means for process plants is being able to install instruments in places where it would normally be difficult to run wires, or to add additional devices without having to incur costs normally associated with wired infrastructure.

There are a number of concerns raised whenever the specter of wireless in the plant is raised. And so suppliers have been anxious to point out how their respective solutions are able to overcome these, which chiefly are worries on security, interference, network reliability, and battery life.

Emerson and Honeywell, the two most active vendors in the sector so far, are also keen to stress that what they are not proposing is moving to a completely wireless environment in the plant. At least initially, the emphasis is on monitoring, not on control, with the extra sensing capability providing much greater knowledge about the process. And wireless is definitely not being recommended for critical control loops or safety systems.

So it’s really the start of something that is set to evolve over the next few years as users become more familiar with the concepts and try out the technology (low cost starter kits are available), and as industry standards are finalized, specifically, ISA’ s SP100.

And as with mobile phones, don’t be surprised to see all sorts of novel applications developing once solid wireless infrastructures are established in the plant.