Procure BACnet System

Procure BACnet System

BACnet was designed to allow communication of building automation and controlsystems for applications such as heating, ventilating, and air-conditioning control (HVAC), lighting control, access control, and fire detection systems and their associated equipment.

The UDP port number 47808 (in hexadecimal, X'BAC0') identifies BACnet messages and is the UDP port used by PAD devices. BACnet/IP devices use this UDP port by default but may be configured to use a different number if necessary. An open protocol should be powerful and robust, capable of meeting all future communication needs, as well as the present needs throughout all system levels. Any communication protocol which doesn't meet these criteria should be eliminated from further consideration.

BACnet's open structure and object-oriented commands enables developers to provide enhancements or features, while still maintaining full interoperability for all core operations. If use of a new control feature becomes widespread and there is a need for it to be standardized among vendors. ASHRAE provides a procedure for it to be adopted as a standard BACnet object or service.

BACnet is a widely accepted, non-proprietary open protocol standard. Companies began announcing their support for BACnet even before the final draft of the standard was released. The fact that ASHRAE developed BACnet plays a significant role in this acceptance. ANSI perceived BACnet to be a significant development and adopted it as a protocol standard within months of acceptance by ASHRAE.

Components vs Systems

For many years the BACnet community has worked hard to ensure that BACnet is a global standard and that it’s implemented consistently across multiple supplier product lines.  BACnet International devotes substantial resources to the BACnet Testing Lab (BTL) and to annual device “plugfests” to support that objective.  We regularly point out that BACnet is a global consensus standard and we trumpet the value of standards.  We talk about component interoperability and in some cases even interchangeability.  All of this is good.  Users need to understand the power of standards and how specifying systems that incorporate BACnet can add value to their building automation investments.  However, by promoting BACnet as standard and then using the shortcut term “BACnet System” we invite the unschooled to mistakenly extend the concept of “standard” from the communications protocol to the system.  That seems to lead some of them to the conclusion that all “BACnet Systems” are essentially equivalent and can be procured like commodity products … even to the point of the “reverse auction” procurement process for an energy management system I recently encountered. 

Reverse Auction Procurement

Reverse auctions have been around for more than a decade.  They evolved as a “simple” way for buyers to drive down the cost of components.  The essence of reverse auctions is that suppliers bid back and forth for a well-defined piece of business on the basis of price.  Full-featured web platforms have evolved to support this purchasing model but, even so, it has its limitations.  One of the biggest limitations is that for it to be effective, the product and its associated transaction attributes (e.g. lead time, delivery date, etc.) need to be unambiguously defined in terms that can be readily measured.  And therein is the rub.  Energy management and building automation systems are complex so fully defining all of the important attributes is a huge challenge.  Leaving any important attribute undefined results in suppliers compromising on those unspecified attributes to achieve the lowest cost and win the business.  On the surface the result might look like a good deal for the buyer.  But those compromises might well come back to haunt the buyer in the long run.

Lessons Learned

It was an attempt to give people new to the BACnet community some insights based on the experience of people who have already designed and operated systems built around BACnet.  One of those “lessons learned” was that a “BACnet System” is still a system. The BACnet standard can make system integration faster, simpler and more effective but it is not a substitute for system expertise, creativity or design rigor.  Nor does BACnet provide any assurance of product quality or system effectiveness.  These come only through knowledge and experience.  So, I encouraged owner/operators to develop a partnership approach to working with suppliers who have that knowledge and experience. I saw first-hand what happens when complex systems procurement is driven from a “first cost” perspective without sufficient focus on supplier partnerships.

Benefits of BACnet Protocol

• Single operator workstation for all systems
• competitive system expansion.
• Eliminates fear of being an owner to be locked in with a single vendor.
• Possibility of integrating all BAC Functions.
  
• Interoperability

·         Data sharing

·         Alarm and event management

·         Trending

·         Scheduling

·         Remote device and network management

Summary

BACnet is a standard. All the necessary elements are in place: strong customer demand, a robust open standard and manufacturer's support of the standard. BACnet seems to provide a complete solution to interoperability issues for building procurement  team.  Understanding the difference is important in establishing a procurement process that builds positive supplier relationships and generates maximum value in acquiring an energy management or building automation system. SSA Integrate can guide how to utilize this.