As LED lighting adoption increases, organizations focused on saving energy are looking more and more to lighting controls as the next frontier for maximizing energy savings and decarbonization. The Lighting Controls Association welcomes these organizations—ranging from the DesignLights Consortium (DLC) to the U.S. Department of Energy (DOE)—to its cause of educating the electrical construction industry about technology and application.
Selecting Lighting Control Systems, a publication by the Pacific Northwest National Laboratory (PNNL) for the DOE, sheds light on the process of designing solutions that both align with project objectives and are clearly documented. PNNL developed this publication in response to research finding that success with lighting controls can maximized by adhering to industry best practices. The result is a straightforward 20-page guide, with additional resources listed ranging from IES lighting practices ANSI/IES-LP-6 and ANSI/IES-LP-16 to the Lighting Controls Association’s website.
The publication is divided into four major parts, covering:
STEP ONE. Establish goals for the control system. In this first step in the selection process, the lighting control system designer engages with the owner or its representative to profile the application, project users, and what the owner wants the system to do, resulting in a document called the Owner Project Requirements (OPR). These goals can cover numerous elements in detail, from preferred vendors to maintainability, but regarding core benefits, they can be categorized into four use cases:
- Energy code compliance: Commercial building energy codes regulate design energy efficiency in the majority of new construction and renovation projects in the United States. These codes impose mandatory lighting control requirements typically incorporating local manual controls, occupancy sensing, time scheduling, daylight response, dimming, and in some cases plug load (automatic receptacle) controls. The primary goal is energy efficiency, with automation often deployed with user overrides to turn the lights On or keep them On at some predetermined level. As energy code compliance is typically a minimum requirement for projects, it forms a baseline use case.
- Enhanced lighting performance: Various lighting controls can be used to enhance occupant productivity and satisfaction by shaping the user experience of the illuminated environment, incorporating value-added capabilities such as tunable-white, scene control, and control of motorized systems such as automated window shades.
- Enhanced energy management: These are energy-saving goals that go beyond mandatory energy code requirements, covering advanced capabilities ranging from sophisticated lighting control strategies to measuring and monitoring to integration with other building systems.
- Enhanced facility productivity: These are goals that leverage building and operational data, captured via an appropriate networked lighting control system, into services such as maintenance, asset tracking, indoor positioning, and occupant counting and patterns.
STEP TWO. Define system capabilities. In the next step, the lighting control system designer identifies what available common lighting control capabilities the system will need to fulfill the intended use cases and thereby satisfy the OPR. All capabilities are defined in a special section in the guide called “Capability Details.” As a visual aid, the document offers a detailed table and the below graphic:
STEP THREE. Evaluate system architecture. In this step, the lighting control system designer evaluates options for delivering the desired capabilities within project limitations, proceeding through decision points related to system scale, networking, communication, and required components.
Scale: The PNNL guide delineates room-based, suite/floor/building systems, and campus/portfolio systems. Room-based systems are able to operate on a standalone basis, though they may be networked for data communication in a larger-scale system controlling a suite of rooms, a floor, or a building. In the case of a building-scale system, the lighting may be fully networked or a hybrid approach may be taken, wherein certain rooms or devices operate independently while others are networked and programmed to share information and operate as a system. Lastly, a campus or portfolio system is essentially a building-scale system but with an added layer of communication enabling cross-building interactions.
Networking: Networking provides data communication between lighting control devices, thereby permitting remote configuration and zoning, complex control behaviors, sophisticated capabilities such as demand response, and the potential for data collection and enhanced systems integration. In a networked system, the control intelligence (where automatic lighting decision-making occurs) may be centralized, distributed, or a combination of the two. As an example, in a luminaire-level lighting control system (LLLC), where intelligence is distributed in embedded controls in luminaires, control points may each connect to a central server for capabilities such as scheduling.
Luminaire zoning: A control zone is one or more luminaires set to respond together to a control signal. Larger zones (with a larger number of luminaires) tend to be simpler to design and impose a lower cost to install and configure. Smaller zones (with a smaller number of luminaires) tend to increase responsiveness, flexibility, and energy savings. Luminaires may be assigned to both smaller zones for certain functionality and larger zones for other functionality.
Wired versus wireless: Control devices may be connected using dedicated control wiring, via a digital wireless network, or a combination of the two, communicating based on a common protocol or using a protocol interface. For example, a building with a wired building-scale networked control system may use wireless communication in various local applications.
System components: The PNNL guide identifies system hardware that are commonly deployed in lighting control systems and defines the role and functionality of each—notably, servers, gateways, user interfaces, sensors, load controllers, and luminaire drivers. Schematic examples are provided for a system with centralized intelligence, a room-based system, and an LLLC system.
STEP FOUR. Document the concept, design, and operation for the system. Following industry best practice, the lighting control system designer produces a Control Intent Narrative identifying conceptually what the system will do to satisfy the OPR, followed by a Sequence of Operations detailing specific behaviors for all control points. Documentation can then be produced for the selected system itself, including specifications and drawings. The PNNL guide identifies the basics of what should be included in each.
In October 2024, the Lighting Controls Association is launching a major update to its lighting control system design course that covers these topics in detail. This material will be shared in an article published during the month. Stay tuned!
DELIVER. Armed with knowledge and best practices, lighting practitioners can identify owner needs, select lighting control solutions that satisfy them, and properly communicate this solution to the design team. Alongside resources such as ANSI/IES-LP-6, ANSI/IES-LP-16, and the Lighting Controls Association’s Education Express, PNNL’s concise Selecting Lighting Control Systems guide is an excellent place to start.
Download it free here.
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