Systems Integration, 2001
-- Consulting-Specifying Engineer, 1/1/2001
In high-technology facilities, building-systems integration is a mixed bag, say engineers, in part because-as always-it depends upon the whims of the client. "The degree of integration of multiple building systems often depends on the owner's organization," says Calvin L. Witt, P.E., of Hayes Seay Mattern & Mattern. "For instance, most security-conscious clients have little desire to depend on an outside network or equipment to provide this function. Therefore, security normally has little integration with other building systems."
CUH2A's Steven. R. Rafferzeder, P.E., agrees: "In most cases, security-while integrated-is limited to access control. Larger security projects with CCTV and microwave sensors tend to be on a separate system."
Still, if one department of the owner's organization maintains all building systems, it is likely to depend on communication between HVAC controls and other basic building functions, says Kling Lindquist's Charles A Rowland, P.E. "HVAC systems commonly interface with smoke exhaust and sensing systems, coordinate with daylighting systems or occupancy sensors or communicate with other buildings." Additional control tasks may include operation of vertical transportation and emergency generation equipment.
In addition, if the HVAC direct-digital control systems have UL 864/UUKL listings, they can handle many smoke-control functions by means of inexpensive software, rather than by engineering hardwired connections to the systems, adds Witt.
The question of how and whether to integrate with fire-alarm systems is a point of much concern, however. "Fire-alarm systems also need to be highly reliable and supervised," Witt observes, "but the HVAC system needs to react to fire detection either by shutting down or by going to a smoke-control cycle." Also, fire departments generally prefer having intuitive, easy-to-use control panels to aid in fire-fighting and executing smoke-purge functions.
Other external factors affect the decision to integrate, says Carter & Burgess' David Niemann, P.E.: "Building codes and system reliability issues sometimes work against systems integration, although open protocols and the wider use of fiber-optic transmission systems will allow integration to occur more effectively."
