"All that is required in most cases is:
- To specify generally available Human Machine Interface (HMI) software, such as those available for SCADA systems; and
- To require that the control systems vendor use a Windows operating system that will send data to a central server running the HMI. The server will provide the graphics and will relate the received data points to the graphic."
I agree conceptually, but my bias would be to force the HMI software to Web-based standards, which may or may not include SCADA. The concept we agree on is that the owner must take a more active role in the integration of large automation projects into the enterprise. The old bid and spec approach does not work well in the new environment, where the enterprise interface has become as important as the end control.
In my August 2001 "Building Automation" column entitled, "Leave Yourself Room For Progress," I talked about the problems specifying when building automation evolves so rapidly. I pointed out the advantages of the Request For Proposal (RFP) approach and below is a brief summary of the major concepts discussed.
- The RFP approach has been proven and used by the Information Technology (IT) industry for years.
- The rapid evolution of control products was, and still is, many times faster than the construction time line for most large projects.
- The concept of removing automation from project design and purchasing it in a "just in time" fashion in an RFP is the solution.
- Products that support the most field bus and IT standards will be the clear winners providing a path to future proofing.
The "just in time" RFP approach will allow the purchase of a leading-edge system based not just on low price, but on technical merit, overall functionality, ease of operation, and lower ongoing maintenance costs.
The Demise Of Bid And SpecHaving set the table on how this conversation began, let's see how it evolves with the help of several leaders in the controls industry. From an interview with Gerry Hull, president/ceo of Automated Logic Corporation and Steve Tom, Automated Logic Corporation's director of technical information:
Sinclair: "The traditional bid and spec approach is giving way to request for proposal and or design-build. What are the pros and cons?"
Hull and Tom: "The pros are that the new procurement methods give you a much better way to take advantage of new ideas and new technologies. The cons are that they're much tougher to evaluate and manage, and it's even more important that the contract goes to a reputable firm that will work with you to overcome thousands of problems and unforeseen events which occur during any major building project.
"There was never a spec written that could force a dishonest contractor to become honest, but at least they "reined in" the ones who were leaning in that direction and gave you a big club to hold over them. The disadvantage was that they also reined in the honest contractors, and forced them to "design down" to the lowest cost system that would meet the technical provisions in your spec. If a new product was available that was better than what you specified, he couldn't afford to base his price on it because it might cost him the contract if it was more expensive, or you might reject it and force him to use the specified item if it was cheaper. The RFP and design-build approaches allow (force?) the buyer and the contractor to become partners, working together instead of sparring in an adversarial role. Like any partnership, you just need to be careful with whom you partner."
My September 2001 column talks about industry restructuring and features interviews with industry leaders Hartman and Zaban. My conclusion is that restructuring is just that, a complete reconstruction of the existing control procurement process and methods of doing business. I find that while many players in our industry feel that only minor changes are occurring, both Toms and Hull point to major restructuring. Restructuring that will change who we are and for whom we work. Equipment manufacturers are not willing to adapt new technologies unless the purchasers of their products drag them kicking and screaming into radical evolution.
The capability of today's building automation systems far exceeds the present understandings of the existing implementers.
Interoperability PossibilitiesCommunication protocols are a large part of the present industry restructuring. In the same interview with Automated Logic, I asked the question:
Sinclair: "How would you recommend that owners handle protocol standards and IT convergence to allow themselves the option of changing control contractors in the future?"
Hull and Tom: "At the IT level, buy systems that fully embrace Web standards throughout. It is the only way to follow the Web wave of new products and services that will be flowing for years to come. At the hvac protocol level, buy BACnet. It is the only protocol out there with the robustness and hvac system features that can handle the job. There are other protocols but every one we have seen is full of too many "gotchas," limitations, and can only be implemented with proprietary fixes and "workarounds." Some look great in the beginning, but in the end they are skilled-labor intensive."
The same question was presented to Kevin Lynch, executive director of the LonMark(r) Interoperability Association.
Lynch: "Clearly, the right path is to embrace the open systems model endorsed by many of the companies in the LonMark Interoperability Association and Echelon's Open Systems Alliance program. Both of these initiatives are all about choosing best of breed products, services, contractors, and integrators. The building industry is moving rapidly to open systems with open choices, get over it or get out."
In an interview with Rehan Kamal, IT strategist at Computrols, he approaches interoperability problems with full Web solution.
Sinclair: "What about interoperability? Can Web accessibility be provided by a company that is not the bas [building automation system] contractor/manufacturer?"
Kamal: "A Web server (that "talks" TCP/IP) product is just that - a Web server would be a window into a building automation system. Other vendors in a building may use this type of access to the bas system. However, this type of access will generally be limited to humans, not other bas controllers or computers. Hence the bas software would integrate equipment from multiple manufacturers, independent of the Web product. This in turn can be placed on the Web. So, although the Web product can be used to integrate multiple vendors, this capability would have nothing to do with the Internet access itself.
"Another avenue would be TCP/IP internet-ready controllers that can be made to have completely open Internet connectivity right down to the controller level. Thus WWW access would be available at the controller level for human-to-controller access. But more importantly, XML and other standards can be used for truly open, third-party, controller-to-controller connectivity. I fully anticipate the industry to move in this direction."
Sinclair: "Any more thoughts on TCP/IP protocol?"
Kamal: "The building automation industry is going the way of Internet appliances. That is ... having a TCP/IP connection to every single device in the building - not just the front end computers. Internet connectivity from PC to PC reached maturity in the late 1990s. Now, there is a huge amount of R&D effort and money going into Internet connectivity for appliances in the home and office. Standards like Blue Tooth, Universal Plug and Play, Jini, HomePNA, and others will drive Internet connectivity in the coming years. Internet appliance technology will reach wide acceptance and become commonplace by 2005. This is not just in the building automation industry, but in every industry that can use that level of connectivity."
Rand Arnold is founder and president of ControlShop, as well as a principal of Objective Automation, a consulting firm focused on the delivery of integrated automation systems based on open standards. He provided the following information in an interview.
Sinclair: "Numerous companies now characterize their systems as 'open.' What do they mean?"
Arnold: "Openness in a product or system is fundamentally a measure of the level of standardization in the nonapplication-specific elements. The degree of openness is effectively proportional to the degree of standardization. Standards are the foundation upon which openness is built. To achieve any degree of 'openness,' certain standards must be established and agreed to.
While the building automation industry certainly has not led the charge in establishing protocol/communication standards, it is slowly recognizing the value. The two standards receiving the most press in our industry are LonWorks and BACnet. Remember, however, that a variety of other standards are also playing a critical role, like IEEE 802.11(Ethernet), the IP protocol suite, and other Internet related standards like XML."
Sinclair: "Can you provide a checklist for designing an open control system?"
Arnold: "I can certainly point out a few key ingredients. For starters, address wiring. The base for building a wide-open control system is intelligent wiring. Starting with wiring grants the integrator and enduser the ability to quickly and easily install the system as well as make additions and revisions in the future.
"Almost as importantly, eliminating the physical barriers between systems encourages engineers and owners to create holistic building control. After the wire is in, examine how the devices will communicate. It is crucial that the devices installed on the common infrastructure share information without effort. So the products must adhere to a common communication guideline. As previously determined, this means the devices must use standard communication variables. This is the purpose of standards like LonTalk and BACnet.
"After communication, consider the effort required for configuration. To make integration easy, a device must not only support standard communication, it must support a standard interface for configuration. Look for guidelines that provide for the physical layer requirements of devices as well as the common data types, configuration capabilities, and installation methodologies. While it's adequate for product manufacturers to simply document the configuration interface for their device, it's obviously better if they encapsulate the knowledge into a program that can be run.
"Once these aspects are nailed down, its time to think about how the system will be tied together. Standard network management services provide the necessary network services and published interfaces for an open infrastructure. These services allow multiple tools from multiple vendors to coexist on the network. More importantly, it allows the various tools to share the network data. Integration is possible without standardized network management, but it is complex and costly.
"A system in today's market is not complete if it does not provide Internet access. The Internet protocol suite is the standard on which the Internet is built. An open control system must provide for encapsulation of the control system messages or packets into TCP/IP datagrams. Messages can then be passed around the world without translation into foreign protocols. The cost of transmission is minimal and the ability to leverage existing infrastructure practically limitless.
"Finally, limit gateways to the extent possible. At any point in the system where the messages between devices is mapped from one communication protocol to another, the control network effectively ends. The 'mapping' of messages from one protocol to another is accomplished via a gateway. Gateways should only be used for interfacing to legacy systems or in situations where standards are unavailable.
"Everyone knows that gateways have been a staple of the commercial control industry for the last 10 years. They often provide a necessary function. They are, however, bottlenecks in the flow of system data and are inherently performance limiting. Performing the functions of a gateway requires processing power, which translates into higher cost. Gateways also require someone to indicate what should be mapped to that which consumes engineering efforts. Finally, gateways are difficult to maintain. Any change in system parameters has to be addressed at the gateway as well. As a gateway is a transition from one communication protocol to another, it almost always is accompanied by a change in network management schemes. Different management schemes mean different tools are required for either side of the gateway."
Will Your Next BAS Run On Baja?Tridium and others are working on a new Java standard to take advantage of the power of the Internet.
Baja (Building Automation Java Architecture) is a standards effort with the mission of creating an open Java platform for the building automation market. Baja is a suite of component software applications designed from day one to take advantage of the power of the Internet, support true plug-and-play, and allow for complete multivendor interoperability.
By using Java APIs and XML schemas, Baja allows developers to converge multivendor device protocols and communication standards with Internet technologies into a single universal standard and adapt them into an open, interoperable environment. The result is a solution that unlocks the potential of smart devices and the Internet in ways previously unimaginable, while providing significantly lower automation and information infrastructure costs.
The expert group shepherding Baja through the standards process consists of many of the major players in the automation industry. They include:
- Tridium, Inc., http://www.tridium.com;
- Johnson Controls, http://www.johnsoncontrols.com;
- Sun Microsystems, http://www.sun.com;
- Yamatake, http://www.yamatake.co.jp;
- Invensys, http://www.invensys.com;
- Echelon, http://www.echelon.com;
- Honeywell, http://www.honeywell.com;
- CPC (Emerson Electric), http://www.emersonelectric.com;
- Siemens Building Technologies, http://www.sbt.siemens.com; and
- The Trane Company, http://www.trane.com.
For more information on this development, be sure to download the white paper, http://www.tridium.com/products/Baja_White_Paper.pdf.