“ISA100.11a Draft Standard Progresses” read the headline on the press release issued by the ISA on October 15, giving an entirely new meaning to the verb “to progress.” What the release was actually announcing was that the second draft of the proposed standard on “wireless systems for industrial automation: process control and related applications” had failed to gain the necessary two-thirds majority in the recently completed committee ballot, which would have allowed its issue as an ISA standard.
That was not the result that had been anticipated by those advocates of the standard who had hoped that its early adoption would put the brakes on the gathering momentum of WirelessHART. This was all the more embarrassing since WirelessHART had just been accepted by the IEC as a Publicly Available Specification (PAS), a key step on the road to its eventual adoption as a full IEC standard. The official line from the ISA, and the story being adopted by those vendors who have made the most public commitment to ISA100 is that this is simply a normal part of the standards making process.
Both voting and non-voting members of the committee and members of the public have commented on the draft and “the committee is now embarking on a defined process of addressing the comments via suitable revisions to the draft. Any substantive edits to the draft will be re-balloted to the voting members for an opportunity to revise their vote.” Despite the project having clearly suffered a significant set back, “The target timetable (for approval) is by the end of 2008.”
That prediction seems to be based on the fact that the draft only failed by one vote, with 64 out of 68 eligible voting members returning ballots of which 40 were in favor and 21 against, with three abstentions. According to Honeywell’s Harsh Chitale, the proposal achieved the necessary two-thirds majority among users and was therefore only voted down by a key group of vendors. However, while that would suggest that only one member needs to change his or her mind or two abstentions to come down on the approval side for the revised draft to be approved, it seems equally likely that the number against would increase if the fundamental concerns have not been satisfactorily addressed before the next ballot.
Lack of clarity
Those concerns seem to have centered ostensibly on the lack of clarity in the draft which, it is alleged, was at some points either confused, contradictory or both. Assurances that key missing sections would be addressed after approval clearly failed to convince all members, while the central issue of how WirelessHART would be incorporated remains wide open. Overriding all these issues, however, and almost certainly the fundamental cause of the draft’s failure to achieve approval, was a general feeling that it was being rushed through for political rather than sound technical purposes. Those suspicions tend to be confirmed by suggestions that attempts had been made to reject certain votes where they came from subsidiaries of another member company on the grounds that only one vote per company would be acceptable. According to one source, that argument was subsequently dropped when it was appreciated that, if uniformly applied across all voting members including both vendors and users, it could disqualify more “fors” than “againsts.”
With the voting so finely balanced, a period of intense lobbying now seems inevitable, with pressure being brought to bear on key individuals and companies to change their position. It would be disappointing for the wider user community, however, if a further ballot approved the draft without substantive changes being made to address the real concerns that have been raised, most notably those about the still unresolved relationship between ISA100.11a and WirelessHART.