NEWSLETTER

Networked Controls For Lighting and Shading Systems

By Joe I. Moreland, PE, CSI (GA PE#26321)
Lighting accounts for the largest portion of a typical commercial building's electricity usage — more than 35 percent according to the Energy Star Building Manual. Consequently, effective lighting control strategies that maximize energy efficiency can provide significant environmental and economic benefits, as well as enhance occupant comfort and convenience, increase productivity, and improve safety and security. Systems that also incorporate motorized window shade controls to regulate the amount of available daylight provide total management of light within a space.

BSD's two new Sections 26 0943 - Network Lighting Controls - Lutron and 12 2400 - Window Shades, featuring basis of design products from Lutron Electronics Company, Inc., may be used to specify lighting and shading control solutions for a variety of project types, from simple standalone systems to more complex whole building systems with centralized PC control and monitoring. Consider the following control strategies when specifying a networked lighting/shading control system.

Scheduling

An astronomical time clock controls lights according to a programmed schedule that automatically adjusts for seasonal changes in sunrise and sunset times. Within a digital-network lighting control system the operating schedule can be programmed to respond to various inputs such as manual override switches or fire alarm/security system interfaces. The system can also flash lights as a warning before turning them off so that occupants have the opportunity to initiate an override.

Occupancy/Vacancy Sensing

Occupancy/vacancy sensors are crucial to maximizing energy efficiency by controlling lights based on the occupancy status within the space. They are available with various detection technologies, mounting configurations, coverage patterns, and features, all of which must be considered in order to optimize functionality and flexibility.

While occupancy/vacancy sensors are often used in standalone applications to simply switch local lighting loads, their function within a digital-network lighting control system is much more extensive. They can be programmed to trigger a multitude of responses, such as adjusting the light output of an individually addressable fixture to a preset level or switching all lights for an entire floor or area. Since the programmed response can be adjusted without the need for rewiring, the system can easily accommodate changes from the original design either during construction or in the future as occupant needs evolve. Wireless sensors are also available for ease of installation, ideal for retrofits and future expansions.

Daylight Harvesting

Daylight sensors are used to control loads according to available daylighting within a space. Control may be achieved by switching, stepped dimming, or continuous dimming of lights. Within a digital-network lighting control system, daylight target levels for each area can be adjusted when the function of a space changes or different occupants move into a space.

Light Level Tuning

Tuning allows for adjustment of lighting output to meet current user needs utilizing stepped or continuous dimming. Quite simply, the more lights are dimmed, the greater the energy savings. Continuous dimming is available for various light sources, including fluorescent, incandescent/halogen, magnetic low voltage, electronic low voltage, neon/cold cathode, and light emitting diode (LED) drivers.

While fluorescent electronic dimming ballasts with continuous dimming down to ten percent may be suitable for most commercial applications, ballasts with dimming down to less than one percent are available for architectural applications such as board rooms and auditoriums. Groups of ballasts utilizing 3-wire control can be dimmed together via control modules, or individually addressable ballasts such as Lutron's EcoSystem® ballasts can be independently controlled for maximum versatility.

A high-end trim sets the maximum light level for a space while local personal dimming controls give the occupants the ability to adjust levels according to their preferences. Wall-mounted controls may include buttons for recalling programmed lighting levels or "scenes." Desktop and handheld remote controls utilizing either infrared (IR) or radio frequency (RF) wireless technology provide additional convenience. Web-based controls such as Lutron's Personna® PC can even allow users to control the lights and shades in their area using a web browser on their PC or mobile device.

Demand Response

Load shedding software such as Lutron's IntelliDemand™ can be used to manually or automatically reduce lighting loads during peak demand periods to save on utility charges and ensure power stability.

Shading Controls

Digital-network motorized shading systems such as Lutron's Sivoia® QS can be integrated with lighting controls. Shade positions can be programmed independently or as part of "scenes," along with preset lighting levels.

Automated shading controls such as Lutron's Hyperion™ Solar-Adaptive Shading automatically adjust shades throughout the day based on the sun's position to reduce glare and solar heat gain in the space. This maximizes the energy saving potential of daylight harvesting lighting systems and can also reduce energy costs associated with HVAC systems. The system can be configured to allow individual users to manually override automatic controls.

Control and Monitoring

Whole building systems such as Lutron's Quantum® Total Light Management™ allow all aspects of the system to be viewed and adjusted through centralized PC control and monitoring software. The software interface can even include customized CAD based drawings of the building to allow for easy navigation and status reporting. Control and monitoring can also be integrated with a building management system (BMS). Real-time and historical energy savings data provides feedback to assess system performance, and can even be made available for public display with energy reporting software such as Lutron's Green Glance™.

Using SpecLink to Specify Lutron Network Lighting Controls

BSD's Section 26 0943 - Network Lighting Controls - Lutron includes an optional checklist which can be used to pre-edit the specification based on the system scope choices selected. Key system scope choices include the following options:

• System type may be either Lutron Quantum® (centralized PC control) or standalone.
• System may control both lights and shades or lights only.
• System control may utilize both dimming and switching or switching only.
• System may utilize wired or wireless sensors, or both.

Except for Lutron's Sivoia® QS motorized roller shades, which are located in BSD's new section 12 2400 (12490) - Window Shades, the section includes most of the key components necessary to specify a complete Lutron digital-network lighting and shading control system:

• Power Panels:  Dimming and switching panels.
• Fluorescent Electronic Dimming Ballasts:  3-wire, 2-wire, and digital control.
• Lutron Grafik Eye® QS main units.
• Lutron Energi Savr Node™ lighting control modules.
• Lutron Quantum® Energy Meter.
• Lutron EcoSystem® digital dimming ballast and switching modules.
• Lutron Quantum® Lighting Management Hubs.
• Lighting management system computers and software.
• Control Stations:  Wall controls, wireless (RF) and infrared (IR) remotes.
• Sensors:  Occupancy/vacancy and daylight sensors; wired and wireless.
• Power and low-voltage control interfaces.

The section also includes various available Lutron services, and the "Warranty" and "Maintenance" articles include Lutron's options for warranty coverage and support and maintenance plans.

Because of the complex nature of this type of system, it is recommended that the specification and drawings be closely coordinated with consultation from the manufacturer identified as the basis of design. If systems of other manufacturers are listed or considered for substitution, the specifier should conduct a thorough evaluation to ensure that the system provides equivalent performance and that other related products will interface properly.

Whether your project requires a simple standalone system or a complex whole building system with centralized PC control and monitoring, we're sure you'll find SpecLink's intelligent linking and extensive master note content to be essential tools for developing your network lighting control system specification.