Roundtable Redux: BAS Retrofits

The M/E Roundtable in CSE's March 2002 issue focused on the past, present and future of BAS technology. These projects, offered by some of our panelists, display some of the potential of BAS in retrofit projects.

03/15/2002


The M/E Roundtable in CSE's March 2002 issue focused on the past, present and future of BAS technology. These projects, offered by some of our panelists, display the potential of BAS in retrofit projects.

Fordham University, Manhattan, New York

Fordham University's Lincoln Center Campus in Manhattan, New York was the first native BACnet system installed in the city. Alerton's BACnet system, BACtalk, replaced the existing proprietary system and is now the backbone for the 900,000 square foot campus making up Fordham's Law School, Performing Arts Center and residence housing.

The first phase, completed in 1997, was planned as a pilot for BACnet at the university. Driving that decision was the foresight of the Director of Facility Operations and the Vice President of the Lincoln Center Campus. The consulting engineers responded with a design that ensured the system would be BACnet compliant at every controller and network device. The goal was to show BACnet as a complete system, a viable protocol for a complicated, expanding campus management system.

The initial installation was a variable-air-volume HVAC system with two 45,000-cfm air handlers. Alerton's Microset Wall Sensors were installed in all of the new classrooms and study lounges, with each having a dedicated VAV terminal. Subsequent installations throughout the campus will require that all global controllers, in this case Alerton's LAN System Integrator, and BACtalk for Windows Workstations communicate over the campus network. The standard IP technology utilized in the BACtalk system meant that the BMS devices would be seen as just another node on the network.

Native BACnet devices, such as Alerton's LSi, that support the TCP/IP make the system easy to use for the technology staff at Fordham. Using TCP/IP over the existing Ethernet WAN provided for flexible and cost effective installation and communications.

With plans for integration of existing boilers, Delta Controls BACnet devices and the successful completion of a Liebert BACnet interface into the Alerton campus system, Fordham is well on its way toward the completion of the University's vision of having the best systems and services while maintaining competition among vendors to the benefit of Fordham.

-Tom Mahrer, Alerton Technologies

One Liberty Place, Philadelphia, Pennsylvania

Anyone who's seen a Bruce Willis movie has seen One Liberty Place prominently featured in Philadelphia's skyline. At sixty-one stories it boasts a unique spire that not only makes it Philadelphia's tallest high-rise, but also the city's most recognizable.

Constructed in the mid 80's, One Liberty was one of the first buildings to employ a head-to-toe, or spire-to-basement, DDC control system. This was a bold move that building owners, operators and tenants have never regretted. However, the leading edge 80's technology was short lived and as time and technology progressed the building operators became hard pressed to keep the extensive system in service. Unable to obtain replacement components it was obvious that the 'rob Peter to pay Paul' couldn't go on forever.

Complete replacement was the only option, and matching the operation and performance of the existing system was not the only concern. Fifteen years of tenant fit-out renovations demonstrated the disadvantages of being held captive by a proprietary DDC system. When EMS Engineering, Inc. of Glenside, PA, was hired to design the replacement system, part of their mission was to identify and pre-qualify vendors that use an 'open protocol,' such as BACnet, to accomplish interoperability.

EMS Engineering, Inc. took its responsibility seriously and went about the task of identifying such potential vendors. However, they soon learned that it's one thing to say you are BACnet and another to be BACnet so as to allow competition through real interoperability. EMS decided to conduct an interoperability test with three vendors that advertised BACnet communication. Advanced Power Control, Inc., which represents the Alerton product line throughout Maryland, Delaware, New Jersey, Washington D.C. and most of Pennsylvania, was one of the vendors selected.

Each vendor participant installed their software on a separate computer and mounted controllers and gateways on a test-bench. Each vendor's controller was connected to a VAV box and the three systems were interconnected through an Ethernet network. Test criteria required that each system had to 1) recognize each other's system, 2) read system variables (VAV box CFM) 3), read setpoints, 4) adjust setpoints, and, 5) control the air valve and reheat coil.

The results of the test were invaluable. One of the vendors was eliminated from consideration when they failed the first communication hurdle (recognition). At the same time, Alerton's native BACnet architecture demonstrated it's inherent advantages. The BACnet architecture, combined with able tech support from Advanced Power Control, Inc., had the system up and running while the other vendors struggled with every aspect of the test.

The project was competitively bid, after which the consulting engineer and owner agreed that the Alerton system represented by Advanced Power Control, Inc. offered the best system and represented the best value.

The Alerton's BACtalk system installed consists of a fiber-optic Ethernet, hosting 30 plus LSi controllers communicating with 1,450 VAV's fitted with Alerton VAVSD controllers. There are also more than 70 air-handling systems interfacing with the smoke control and fire alarm systems, not to mention the building's exterior ice and snow melting system.

The chilled water plant at One Liberty consists of 3 cooling towers, 10 pumps and 3 Trane Chillers that will communicate with the Alerton BACtalk system via a Trane BCU gateway. Modbus protocol will be used to control the cooling tower fan VFD's, condenser water pump VFD's and free cooling cycle.

-Gil Schonour, P.E., EMS Engineering . EMS Engineering, Inc. of Glenside, Pennsylvania is a multi-discipline consulting firm offering a wide variety of mechanical and electrical services. EMS specializes in building automation systems and controls interoperability.

Federal Complex, Chicago

he E. M Dirksen Federal Courthouse, J. C. Kluczynski Federal Building and U.S. Post Office comprise this complex in downtown Chicago. The conversion to an open, enterprise-based facility management system for this complex began in 1995. Through a series of competitively bid projects, all of the mechanical HVAC systems, power monitoring, lighting control and perimeter security have been converted to an Enterprise Facility Management System for all 2.5 million square feet of the complex.

The challenges over the last seven years have been many:

  • The high security complex was occupied throughout the conversion.

  • Phased implementation was required.

  • The facilities contained a variety of legacy proprietary control systems.

  • The GSA wanted to realize the true benefits of device level integration through the implementation of a LonWorks-based open control system.

  • Demolition of all legacy systems was required to clean up the systems.

  • Many floors required escorts at all times.

  • Technology continued to advance and the latest advancements were integrated into the design.

  • Several system integrators were working within the facility at the same time. Their efforts had to be coordinated.

  • Enterprise Facility Management was integrated into the system to improve access and reduce future costs.

  • EMD is maintained by GSA personnel while JCK utilized privatized maintenance contractors.

The result of the project is one of the largest open-control systems in the world. This award-winning project consists of control devices from eleven different LonMark control manufacturers controlling over 75 air-handling units, 1,300 VAV box controllers, intelligent sensors, lighting, security card access and a multitude of other support systems serving the 2,000,000-sq.-ft. complex.

Teng & Associates of Chicago designed the multi-phase mechanical and control system upgrades under a General Services Administration Region Five Contract. The Complex had been plagued with temperature control problems for many years. Tenant comfort, energy savings and competitive bids for all phases were the primary concerns. Teng designed the system based on state-of-the-art open-control system technology. Beginning with the federal courts, the GSA implemented a series of competitively bid projects to address the mechanical and control system problems thoughout the entire facility. The temperature control systems for the federal courts went online starting in 1997. The successful installation eliminated temperature control complaints and saved a substantial amount of energy (over 60%) without disrupting the day-to-day operation of the courts. The remainder of the Federal Complex was completed and online by July 2001.

-John Huston, P.E., Teng & Associates





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