Increasing the value of lighting panelboards
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A lighting panelboard is one of the most important, and yet invisible, pieces of equipment in a commercial, industrial, or institutional facility. While a lighting panelboard does the crucial job of protecting branch circuits from overcurrents, it typically is mounted on the wall of an electrical room and forgotten, unless an electrical-related event occurs.
Conversely, an intelligent lighting control panelboard combines branch circuit protection and control into a one-panel solution, creating both space savings and the opportunity for substantial cost savings by turning lights off when they aren't needed. This is made possible by a controller inside the panelboard that operates motorized circuit breakers, turning off lights and other loads when the building or sections of the building are not occupied.
In the past, consulting engineers achieved this functionality by designing a separate control panel typically located adjacent to the lighting panelboard. Branch circuits feeding the building lighting were routed out of the lighting panelboard, into the control panel, and then out to the building's lighting fixtures. While branch lighting circuit control was achieved, it was at a much higher cost in terms of labor and space. Additionally, such control panels fall under the requirements of Articles 110 and 409 of the National Electrical Code (NEC), which require them to be listed and rated for the available fault currents.
Intelligent lighting control panelboards are a more effective solution than such configurations because of their design integrity, integration, reliability, and control features. The energy savings an intelligent lighting control panelboard generates over its lifespan also creates real bottom-line savings for the building owner and facilitates a return on investment that pays for the equipment many times over. For example, a typical intelligent lighting control panelboard has a payback period of two to three years; over a five- to 10-year span, it will pay for itself three times or more. Additionally, if a lighting control panelboard's controller is integrated with a building management system, the information it provides can lead to even more energy savings.
What's more, today's intelligent lighting control panelboards can evolve to meet future energy management needs. For example, due to low energy costs, there was little desire for remote access of a building's lighting control system 20 years ago, but today remote access is a feature relied upon by many building owners and facility managers who are busier than ever and find themselves out of the office at a moment's notice.
Likewise, utility demand response programs are expected to grow over the next five to 10 years, creating an opportunity for building owners to capture significant savings by shedding loads during peak demand periods. Intelligent lighting control panelboards already possess the capability to be integrated into an energy management system for this purpose. Ultimately, this means a lighting control panelboard can be viewed as an investment in energy management that delivers tangible savings over its lifespan.
Consulting engineers strive to minimize their customers' equipment lifecycle costs, which include an electrical contractor's labor costs, as much as possible. Obviously, a lighting panelboard with an adjacent control panel will take up at least twice as much space as an intelligent panelboard in a crowded electrical room, but installation costs also are higher in such a configuration. Electrical contractors typically budget about 45 minutes per circuit to add a relay in series with the branch circuit breaker. An eight-circuit lighting control panel would require about six hours to install—the same time it would take to install an intelligent lighting control panelboard. A 42-circuit lighting control panel would take more than 31 man-hours to complete and introduces many more opportunities for mistakes, which adds cost to an already labor-intensive solution.
Design integrity is also an important consideration for consulting engineers. Specifying robust lighting control systems that are both reliable and safe are key concerns. NEC Article 409 requires that control panels housing relays or contactors must be marked with a Short Circuit Current Rating, which must be equal to or greater than the available short circuit current where the equipment is installed. Proper field inspection is necessary to verify compliance of lighting control panels mounted adjacent to lighting panelboards in an electrical room. Alternatively, lighting control panelboards bring branch circuit control and protection into a single motorized circuit breaker. These circuit breakers are UL-listed and carry an amperage interrupting capacity rating that reduces the need for detailed field inspection.
To reduce future lifecycle costs for the customer, consulting engineers also must look at long-term maintenance needs. Today's intelligent lighting control panelboards feature remote setup, maintenance, and monitoring via a building's local area network or even over the Internet. Instead of hard-wired connections between relays and circuit breakers, as is the case with a control panel mounted adjacent to a lighting panelboard, intelligent lighting control panelboards may be reconfigured via programming changes without the need for costly wiring modifications. While reconfiguring a lighting control panelboard may be done remotely by facility personnel, physically rewiring an adjacent control panel will require an electrical contractor and often involve shutdown of the equipment. Additionally, because some intelligent lighting control panelboards feature remote access via the Internet, changes can be made at night, on weekends, or during business travel or vacations.
Finally, future costs can be minimized by making sure all intelligent lighting control panelboard information is clearly marked, visible, and current, like a standard lighting panelboard. This reduces costs by saving an electrical contractor's time in ascertaining key information about the system. In addition to including standard system specifications, savings can be gained by simple tactics like making sure backup circuit breakers are readily available in case future needs arise.
Making the choice
Theoretically, a lighting panelboard offers an infinite return on investment because it reduces a building owner's risk by protecting occupants, equipment, fixtures, and the building shell itself from the effects of an electrical fire. However, while that value is crucial, it can't be measured. It can be measured for intelligent lighting control panelboards, which consulting engineers increasingly are viewing as a source of quantifiable revenue.
Energy-efficiency improvements, like lighting controls, create real energy savings for the building owner. Accordingly, the lifecycle cost of an intelligent lighting control panelboard should be examined in relation to the incremental energy savings it generates over its life. The result is a lighting control system that actually generates cash flow for the building owner. In fact, as the cost of electricity continues to rise, lighting control panelboards will generate even more savings over the long term.
Given the uncertainty of tomorrow's energy challenges and the energy management means necessary to meet those challenges, the intelligent lighting control panelboard is poised to be much more than a gray enclosure in an electrical room.
Read more about lighting controls in Ken Lovorn's " Retrofitting office lighting controls "
Hickerson is a lighting control specialist with the Installation Systems & Control Business Unit of
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