PacBell Lighting Snag Calls For Handy Upgrade
While the choice to not integrate lighting proved unfortunate, the four-story center was still considered state-of-the-art for its time and included several forward-thinking amenities. One example was the 38,000 miles of conduit, single-strand fiberoptic cable, and single-conductor copper cable to integrate four different communication technologies. Even more uncommon are the 6,688 audio speakers around the building that play "white noise" to minimize the distraction of nearby conversations and work sounds.
Elsewhere, its hvac plant uses water from the 10-acre lake to generate 1 million lb of ice each night, which is then melted the next day to cool the center and its 7,000 employees, saving approximately 20% in energy costs. Light sensors around the quad-wing facility automatically activate each wing's window blinds to open or close, depending on the amount of natural illumination that is supplied through daylit windows. And finally, a Johnson Controls (Milwaukee) energy management system used a single computer (almost unheard of 14 years ago) to control the hvac, safety, and security systems spread across the center's 2 million sq ft.
Back To The FutureHowever, as the saying goes, a building's Y2K strategy is only as good as its weakest system. The current problem was uncovered during a routine Y2K compliance review, suggesting that New Year's morning might bring with it an inoperable and/or malfunctioning lighting control system. One remedy would have been an expensive and inconvenient replacement of the entire lighting control system, entailing new panel enclosures, new relays, and rewiring of the entire facility.
Given the building's 142 lighting panels, more than 5,400 relays, 25,000 light fixtures, and 50,000 lights, this option would have cost roughly $400,000 and predictably did not appeal to the owners.
"We needed a more cost-effective solution and also were looking for a system that would seamlessly integrate with our existing building automation system," says Mike Lyons of ABM Engineering Services (Los Angeles), which runs the facility.
After consulting with various parties, Lyons discovered through Johnson Controls that Triatek, Inc. (Norcross, GA) offered Y2K lighting control upgrade kits that used the existing panel enclosures and relays to upgrade the system at much less expense than a wholesale replacement. Features of the kit include a direct interface to the existing energy management system in the center, plus its own central processor (CPU), mounting backplate, relay interface boards, color-coded (with the original lighting system) three-pin connector with 12-in. "pigtails," spade connector for switch wiring, and butt splices for connecting the pigtails to the low voltage coil on the relays.
Finding this a welcome alternative to gutting the existing setup, Lyons tapped Triatek to configure a cost-effective solution.
Installation? A Snap (Literally)With 142 lighting panels in the existing system needing upgrades, the easy installation of the upgrade kits streamlined the process. First, all existing low-voltage equipment was removed from the 142 panel enclosures (while leaving the existing enclosures and its 32 relays intact) in the PacBell Center. Then, the CPU and relay interface board of the upgrade kit were "snapped in" to the low-voltage section of each panel through their mounting backplate.
With the kits available in 8-, 16-, 32-, 48-, and 60-relay configurations to match the number of relays in the existing panels, the installation team simply opted for the 32-relay configuration on each kit to match the original relays. Finally, the color-coded, low-voltage, three-pin connector was butt-spliced to the low-voltage wires on each existing relay. The three-pin connector provided an easy connection from the relays to the relay interface board, allowing the relays to be controlled through the Y2K upgrade kit.
Typically, power from the existing 24-vac transformer would have been connected to the upgrade kit, but the existing transformers had a ribbing cable that required their replacement. Once the new transformers were installed, the upgrade kits were connected to the new transformers. Just like that, the PacBell Center now had a Y2K-compliant lighting control system for $175,000 less than the cost of a conventional replacement.
"We got the best of both worlds - an easy retrofit that saved us money, plus an integrated system that now allows lighting to be controlled from the same workstation that controls our hvac, security, and fire systems," says Lyons.
Improved Flexibility, TooAs Lyons mentions, the Y2K crisis did turn out to be somewhat of a blessing in disguise. The PacBell Center increased its operations efficiency as a result, because each upgrade kit came with an RS485 communication interface that allows the Triatek system to interface directly with the existing Johnson Controls system without any protocol converters or additional hardwiring.
Hence, schedules created in the Johnson Controls workstation could now provide automated control of the PacBell Center's relays and 50,000 lights. The existing textual graphic display with site floor plans and lighting zones was enhanced to show real-time user feedback for each lighting zone. One click of a mouse now turns each lighting zone on or off, and Lyons and his crew can check the status of all connected relays and lighting zones in the facility.
Flexibility in changing the settings on the 142 upgraded lighting panels is provided through connections to all of the 4,500 relays scattered throughout the facility. The operator workstation communicates with each panel via a three-wire RS485 serial communication network. Each upgrade kit provides the capability to assign 24 programmable switch inputs to any of the kit's 60 zones via pushbuttons on the unit or from the workstation.
According to Lyons, the smooth integration between the lighting system and the building automation system also saved the expense of paying for training and maintenance on two separate systems.
Lyons and his crew also opted to upgrade the network control modules of their energy management system network to the Johnson Controls 300 Series for better network performance. This upgrade also allowed for Lyons to provide remote telephone override capability, allowing up to 8,191 authorized employees to override the lighting schedule for their particular zone(s) via phone, in the event that they need to vary lighting schedules for after-hours work or other facility needs. Moreover, the circuits can also be accessed off-site by a laptop computer loaded with Triatek's LP-PK programming software.
"The flexible lighting schedule programming comes in handy when the facility needs to vary its regularly scheduled 'on-off' modes - such as when we will celebrate the advent of the year 2000," notes Lyons.
That year 2000 celebration now promises to be the kind of glitch-free event PacBell and every other company desire.ES