In the absence of operation-and-maintenance personnel with the requisite level of knowledge and skill, “You would need to be sure that you have the necessary support from the different suppliers to avoid finger-pointing in the event the systems don't cooperate as expected and required,” Newman said.

Summary. Despite improved capabilities for developing multivendor networks, the survey participants urge caution.

3. Is it practical to remove GUI development from a controls contract and employ someone who specializes in developing GUI using standard server-based tools?

“Yes, that is the preferred approach …,” designer Lehr said. “We are using it on larger projects.”

Controls integrator Dutt sees it as practical only in situations in which an owner is seeking competitive bids.

“If the owner is happy with the current solution they have, then it is better to leave the interface and controls to be supplied from a single vendor,” Dutt said. “In my experience, most building managers are looking to work with controls contractors they can trust to do a good job.”

Manufacturer Zaban said he can think of only one case in which it would be practical: “A university has multiple vendors supplying various automation systems to its campus. The contracts call for basic graphics to be created and commissioned. Then, after the job is done, the university retains a different company that re-uses the graphic annotations of the base contract, but slides in a completely new graphic and gussies things up using the tools of that specific vendor so that the final graphics are very consistent with all of the previously completed buildings on campus. The university gets the value it wanted in the graphic (a relatively intuitive collection of dynamic data on one screen), but tosses out the base image because it is not worth the money and time fighting the original contractor because they used the wrong shade of gray.”

The tools used to create the content of interactive Web-accessible displays are almost entirely manufacturer-specific, advanced user Newman said.

“Some suppliers use commonly available software, such as Microsoft Visio, to develop their system graphics, while others use entirely proprietary applications,” Newman said. “Even if the format of the graphic is ‘standard,’ the display of real-time data, archival trend data, or other database information requires manufacturer-specific ‘callback’ routines to collect the data and present it to the server. If, as is common, the graphic is stored in a proprietary format, it is the job of the manufacturer's server to interpret the graphic file, render it into Web-displayable form, and ship it to the browser. All of this is not to say that there are not contractors who are competent with vendor XYZ's GUI-development tools. If your server is from XYZ, you certainly do have the option of hiring a third-party contractor to develop or extend the GUI.”

Summary. The survey participants have mixed opinions as to whether it is preferable to have the manufacturer supplying the controls for a project also provide the graphics because proprietary display-development tools will have to be employed no matter how a graphical interface is procured. The opinion appears to be that there is rough equivalency among the capabilities of various manufacturers' graphics software.

4. How far down into control-system architecture should designers push to replace specialized HVAC control components with more-standard general-purpose IT products?

“There is some argument to say the marketplace should determine this issue,” designer Lehr said. “However, in response to the question, if pushed, it should be down to the router (Ethernet) level.”

Because of current building practices, replacing specialized HVAC components with more-standard general-purpose IT products is practical only to the building-controller level, controls integrator Dutt said.

“Most application controllers are required to be commissioned before the end of a project,” Dutt explained. “This makes it difficult to cost-effectively deploy IT-based controls at the application level. If the owner of the project is a stakeholder in the IT-based solution, then it is possible, but it will take a significant amount of effort to ensure the design survives the construction phase. Currently, it is cost-effective to deploy IT networks to the building-controller level, as this network typically can be installed during construction and can be used during system commissioning.”

Manufacturer Zaban believes: “We're already ‘all the way down’ from an architecture perspective. … Most designers just don't know it yet.

“Now that we have a decent standard open protocol — ‘decent’ meaning well-defined, popular, and, most importantly, extensible — we can go ahead and write BIM (building information modeling) algorithms that would fully specify all aspects of building controls,” Zaban explained. “That means controller profile, network, sequence, interoperability, database, alarm, commissioning, wiring, documentation, service information, and even part numbers.”

A BIM BAS model is a “pet project” Zaban said he has been “threatening to do … just to shake up the industry a bit. …

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