Mel Protacio's BMS Page
Building Management System
The Benefits and Risks of Open Protocols in Building
Management Systems
MAJOR BENEFITS
- True vendor independence is paramount. Open protocols permit the purchaser to mix and match various manufacturer's components in the same building system for individual solutions to building control situations.
- Open protocols allow interoperability of different vendors' systems and components which contributes to satisfying individual end-user needs. Interoperability provided with open protocols can be expected between lower level components of one vendor and higher level components of another, thereby increasing customer choice further.
- The interoperability and vendor independence of open protocol usage achieve flexibility and greater control over system choices for building owners and managers. More control and responsibility go into owners' and managers' hands for the future procurement process of building systems, whether in designing or upgrading.
- Competitive offerings for system upgrades and expansion become more dynamic. As mentioned in reference to various government agencies, open bidding will be facilitated because there is no longer the need to rely on a single vendor.
- End users believe overall quality and operational efficiency of building performance will increse in the long run by integrating systems with protocols. It was viewed that energy efficiency may also increase.
- Building operations may create labor savings with central control, as a fewer number of trained personnel are needed to oversee integrated system operation.
- The ability of building systems to share information when integrated with open protocols is a great asset. Integrated system functions are interactions that take place between separate building systems which allow the individual systems to operate more effectively.
- Open protocols have some advantages over the use of standards. Open protocols are more readily changeable and therefore can adapt to new technologies swiftly. One should bear in mind, however, that certain benefits of open protocols cannot be realized until there are recognized industry standard protocols. Many of the management chores for a multi-vendor system can be greatly reduced when the system is certified to be in conformance with the standard protocol(s). The adoption of standard protocols may cause less confusion in the marketplace.
ASSOCIATED RISKS
- There is a danger that multiple systems merged together on an open or standard protocol will exhibit "lowest common denominator" performance and therefore some functionality of systems may have to be relinquished. Such an integration scheme wouls have system-wide access to only those features and capabilities common to all the systems and could only access improvements made to these systems at the rate by which the protocol changes and the slowest vendor changes.
- Increased costs may be incurred when using systems with open protocols. First costs for complex integrated systems may increase as well as expansion, care, and maintenance costs.
- Operational problems could arise when interfacing with components and systems from multiple manufacturers. Difficulties with trouble isolation and pinpointing the source of problems in mixed systems could occur.
- The use of open protocols also opens the door for underqualified and/or undercapitalized suppliers to enter the marketplace, risking quality assurance.
- Another drawback perceived by end-users is the loss of flexibility and confusion in the marketplace if several open protocol versions were accepted.
- An open protocol-based integrated system is very complex. Highly skilled professionals are needed to install and operate the systems. Engineering and operations staff may need to be cross trained in the function of all systems.
- Manufacturers are unlikely to agree on an open protocol for competitive reasons. This, again, may cause confusion and delay in marketplace development.
The use of systems that incorporate devices made by different vendors underscores the importance of careful system integration and makes good initial design work more critical. Additionally, systems must be tested to make sure each component is performing to its specifications. A multi-vendor system places more responsibility on an owner to understand the component devices and the operation of the system. There are several communication protocols being used in BMS but no particular protocol has been specified yet as a standard.
DEFINITION OF TERMS
Standard Protocol is one that all vendors who wish certification from a standards organization.
Open Protocol is available for public use and may require a usage license and be protected by copyright and patent laws. The use of an open protocol is voluntary and there may be no certification process.
Proprietary Protocols are widespread, but they specifically link a single developer's equipment-thus the movement towards standard protocol.
Interoperability occurs when devices which use the same standard and services but which do not provide for assurance of identical dynamic performance.
Interchangeability occurs where devices which perform the same functions and services in the same manner have the same dynamic performance. Interchangeability enables a user to substitute a device from one supplier for a similar device from another supplier without loss of device functionality and without sacrificing the degree of integration with the host system.
Reference "Communications in Building Management Systems" - Clapp, M.D. (Satchwell Controls)
Other Pages....
Communication Protocols used in BMS
Satchwell Controls BMS
First Philippine Energy Corporation
Email: melprotacio@mailexcite.com
