Luminaire-Integrated Controls
Below is Craig DiLouie, LC’s contribution to the March 2017 issue of tED Magazine. Reprinted with permission.
The lighting controls revolution features three notable trends promoting integration of control with light. The latest commercial building energy codes promote complex control schemes. The LED source is highly controllable. And sensors and microprocessors have become miniaturized. Just as the luminaire has become a device integrating light source and fixture, a growing number of luminaires now also integrate sensors and controllers.
In a typical traditional lighting system, hardware (luminaire), sensors (control inputs) and lighting controllers (microprocessors governing control operation) are installed separately. Sensors are connected to luminaires, and control inputs may be aggregated at a control panel featuring a controller.
The ongoing miniaturization of sensors and controllers allows both to be embedded in luminaires, while volume manufacturing has reduced their cost. The sensors send occupancy and daylight input signals to the controller, which decides whether to reduce or increase light and by how much. This reduces both control wiring while potentially eliminating the need for centralized equipment such as control panels, providing advantages applicable to both new and existing construction lighting projects.
“This approach reduces the total number of devices to be wired, saving valuable time and effort for the installer,” says Eric Jerger, General Manager, Lighting Systems, Eaton. All the installer has to do is bring power to the luminaire, reducing potential error points in the system such as powering and running control wiring for discrete sensors. “Further, it reduces complexity and enables more granular and accurate control, equating to lower energy consumption.”
By reducing complexity, sophisticated control schemes can be layered on the luminaires to satisfy granular energy code requirements and maximize application efficiency. “Embedding an intelligent networked control device directly into a luminaire allows owners to unlock a key energy-saving feature unique to LEDs—energy-efficient dimming—without the complex wiring challenges typically associated with traditional centralized dimming systems,” says Bruce Bharat, Director of Product Marketing, Acuity Brands. “This allows luminaires with embedded networked controls to deliver just the right amount of light exactly when and where it’s needed.”
Options
Typical controls include occupancy and daylight sensors in additional to lighting controllers. The system may be room-based, with autonomous plug-and-play installation based on self-commissioning or a preset sequence of operations. Alternately, the system may be networked for device communication and interaction, scheduling, data sharing and monitoring.
The networking may be wired, typically using 0-10VDC or a proprietary protocol. DALI is gaining ground, however, and DMX is becoming more popular as more manufacturers begin to offer color tuning as an option.
Alternately, the luminaire may feature a wireless communication chipset, which allows it to send and receive data. Wireless control is gaining favor among installers due to simplified installation, with ZigBee or a proprietary protocol (which may be based on ZigBee) being most popular. Other possibilities include Wi-Fi, 6LoWPAN, Thread, Bluetooth, LTE, EnOcean and Z-Wave. Whatever protocol is selected, it should offer reliable communication, scalability, self-healing pathways and security.
Networking allows luminaires to be grouped and programmed with individual sequences of operation. Further, it enables monitoring of luminaire status and measurement of energy consumption. “When networked and connected, individual integrated luminaire controls provide high-density information on presence, light levels and lighting energy use,” says Manuel Oomen, Senior Director of Product Marketing, Philips Lighting.
By adding devices such as temperature sensors and positioning beacons, new information can be collected and shared with other systems such as the building management system (BMS). “Luminaire-integrated controls add sensors that today largely only affect lighting functions,” Bharat says. “The sensor of tomorrow, embedded in the light fixture, can collect information to feed into HVAC and security systems, enable indoor positions, and unlock the future of what the Internet of Things promises us.”
Lighting stakeholders with varying technical expertise, such as designers, installers, end-users, etc., may set up and manage these systems using software. “The right software tools allows all stakeholders to easily complete commissioning, configuration and control tasks with minimal training,” Jerger says, adding it should also provide an intuitive user experience based on the size and type of device (laptop, smartphone, iPad, etc.).
“When software is divorced from the hardware, issues arise,” Bharat notes. “We must recognize and design the system as a platform with integrated hardware and software, just as the sensor integrates into the luminaire. When that occurs, capability and functionality increase while complexity, maintenance and defects decrease. A distributor should look for an integrated platform that also offers mobile configuration with an app, or more advanced setup and monitoring via desktop software.”
While the above provides a significant number of capabilities of luminaires with embedded networked intelligent controls, one’s mileage varies depending on the selected solution. There are many approaches, configurations and feature sets available among manufacturers, sometimes offered by the same manufacturer to appeal to different applications.
DLC specification
In May 2016, the DesignLights Consortium (DLC) released a specification for networked lighting controls, which is the basis for the Qualified Products List for Networked Lighting Controls Systems.
Many utility rebate programs use the DLC’s Qualified Products List for LED products to qualify luminaires, and the new List is expected to result in networked lighting controls being more prominently featured in these programs. Substantial utility support would create a major driver in demand for these systems. In its market evaluation, DLC identified about 40 systems on the market that are likely eligible to qualify. As for December 2016, 15 products from 12 manufacturers received listing.
“The new DLC Qualified Products List provides a standardized method to compare advanced systems from various manufacturers, much like the original Qualified Products List did for LED products,” Jerger says. “With the DLC Qualified Products List, utilities can create rebate programs that have consistent criteria, and the specifier has a reliable checklist of capabilities when designing a facility.”
Opportunity
In its recent LED energy-savings forecast, the U.S. Department of Energy (DOE) predicted that connected lighting and lighting controls would account for one-third of all LED lighting energy savings by 2035.
DOE plans to promote connected lighting, increasing penetration from a current one percent to 28 percent in the commercial sector by 2020. By 2035, DOE forecasts 73 percent penetration in the sector.
As part of its push, DOE developed a connected lighting test bed to characterize the capabilities of market-available connected lighting systems. The results will increase visibility of what works while highlighting improvement needs related to interoperability, complexity and other issues.
The challenge for distributors is to gain knowledge about specific systems to properly match required components to the desired operation, Bharat points out. “This can be mitigated through manufacturer-led trainings, installation of interactive displays in distributor buildings, and manufacturer system design guides,” he adds.
Jerger believes this investment can pay off in a big opportunity. “Luminaire-integrated controls are solving new and complex problems that are no longer limited to lighting,” he says. “Distributors have a unique opportunity to add even more value by aiding their customers in designing a solution that reduces the total installed cost of the system, provides guaranteed compatibility of the control and luminaire, earns rebates dollars for advanced control functionality/energy savings, and enables building owners to collect more data about their facility such as occupancy trends and asset location.”