Convergence-or Not. That's the Question

Aug. 30, 2010
The People in Control Here Are the End Users, but Convergence Isn't Going to Happen Unless They Require It
By Walt Boyes, Editor in Chief

Much has been made of the "end-user revolt" earlier this year at the ISA100 meeting in Orlando. The group of large end users, in the sincere and correct belief that they were also representing the views of smaller end users in general, told the major automation vendors that they were tired of wireless wars, and they wanted a sincere convergence effort between WirelessHART, now IEC62591, and ISA100.11a-2009. This revitalized the ISA100.12 committee, which had been established to explore convergence.

Recently, I did two surveys. One, of end users, found that over 50% of them felt that the wireless standards war had either delayed a decision on implementing wireless sensors or made them investigate alternatives to wireless. In another, of members of the ISA100 committee about whether they really believed in convergence between IEC62591 WirelessHART and ISA100.11a, 23% said "yes," 34% said "maybe," and 43% said "no."

So we have a serious problem with the adoption of wireless field devices in the process industries. Now that the Chinese WIA standard has been approved by IEC, we are very close to having four standards. The drive of the ISA100.11a team to produce a new version of ISA100.11a-2010 could actually produce a fifth standard, since the ISA100.12 effort is to converge WirelessHART with the existing ISA100.11a-2009, which was never approved by ANSI, and which will be different than ISA100.11a-2010.

The worst case scenario is that wireless field devices may get relegated to the marginal applications where they have always been used: rotating machinery, remote transmitters in pipeline SCADA systems and environmental monitoring systems, and some others. If end users start considering alternatives to wireless in process plants, there are two: wired HART with multiplexers and Foundation fieldbus. My survey revealed that at current pricing for wireless devices, those options are finding great favor.

The people who are in control here are the end users. But they have to stand up, stick together, and insist on an honest convergence effort between WirelessHART, ISA100 and the WIA standard, if possible. One of the respondents to my ISA100 survey said, "Technically, there is no issue. Both base specs were developed under the same premise. One is constrained only by the applications layer that was adopted. The base networking is almost the same. The better answer is—can the supplier community ever come together to meet the users expectations?"
It can if end users insist. Most end users ignored the Fieldbus Wars, wound up with an eight-headed hydra of a standard, and then they didn't adopt the products because there were so many standards they couldn't decide. The same thing can happen to wireless.

There are differences between ISA100 and IEC62591 WirelessHART, but on balance, they do the same things, and WirelessHART already has over 1400 end users who've installed systems. Even though many end users are doubtful of the value of the stranded data in existing HART transmitters, most observers feel that once that data is easy to extract and use, it will be seen as extremely valuable. Yes, it is possible to extract the data and transmit it over a non-WirelessHART network—but the majority of end users want something simple to use, and they may perceive that as "too hard to do."

Some end users and vendors are working very hard to make convergence work. But convergence isn't going to happen unless the end users require it.

Come on, you know what it will take. So either do it, or get happy with the idea that there will be five standards for you to select from and bet your career on.