Specifying LED Panel Lighting

When specifying LED panel luminaires, there are choices and specification details to pay attention to so that the right lighting is produced for the location where they will be installed. The Master Format section number commonly used is in the 26 50 00 series for Lighting and specifically in 26 51 13 for Interior Lighting Fixtures. (Corresponding Omni Class Codes and UniFormat II codes if used should be verified by the specifier). Some of the relevant items to address in a standard three-part specification format are highlighted as follows.

Part 1 General

Specifying panel LED luminaires for quality control is a matter of referencing testing standards. In addition to common Underwriters Laboratory (UL) ratings for dry or damp locations, IES recommendation and practices described in the current versions of standards LM80, LM79, TM21 for lighting fixtures are appropriate. These tests indicate the longevity of the tested LEDs used in the product among other things. Note that the photometric reports from these reports represent absolute photometry in this case not relative photometry as for other types of lighting fixtures. Note also that additional IES TM standards are currently under development in an effort to better define LED luminaire performance characteristics and may be available soon to reference as well.

Submittals requested for LED panels should be the same as any other luminaire including manufacturer's product information and lighting output information. Obviously this information is needed during the design process as well in order to create the ceiling lighting plan, but during the construction phase the submittals should be used to assure that the luminaires designed around and specified are the ones ordered for installation. This will help with checking final coordination with the specific ceiling type being installed and integration with other project requirements such as green building and energy performance criteria. It is also appropriate to request a full warranty on the LED panels with a minimum 5-year warranty on all aspects of the luminaire available from manufacturers.

Part 2 Products

As with all products, there are a number of options and choices for specifying LED panel luminaires. Some of them are listed as follows:

• Size: Standard ceiling fixture sizes are available and should be selected as 2x2, 2x4, or 1x4 luminaires with location sizes shown on ceiling plans.

• Mounting: Recessed or surface mount luminaires need to be specified or indicated in a lighting schedule if both are used.

• LEDs: Commonly the LEDs used in the luminaire should be specified as long-life (50,000, 75,000 or 100,000 hours). They should also be binned using a 3-step MacAdam Ellipse process and mixed to provide uniform light output and color across multiple fixtures.

• Light color: LED panels can generally be specified with a CCT of 3,000K (warm), 3,500K (warm neutral) or 4,000K (neutral) and a CRI of 82 – 85 depending on the CCT selected.

• Driver: Constant current drivers with power factors at 99.6 percent for both 120 and 277 V systems are available. If dimming is required, then the driver should be specified to dim from 10 to 100 percent.

Different LED light panel sizes and lumen outputs will require different electrical wattages as compared in this chart. Chart courtesy of RAB Lighting, Inc.

• Wattage/light output: The total wattage of an LED panel luminaire will vary based primarily on the fixture size and the desired light output levels specified. Color choice and the addition of a dimmer will also impact wattage, but to a lesser extent. For example 1x4 and 2x2 LED panels may require 34, 41 or 52 watts for the entire luminaire depending on choices made while a larger 2x4 model can require only slightly more power at 44 or 59 watts. Light output will vary based on the selections made between 75 to 110 lumens per watt (lm/W). Manufacturers' data should be consulted to be sure that wattage and light output are properly understood and specified.

• Luminaire lens: The lens is usually integral to the luminaire and can be specified as high-transmission acrylic with excellent light distribution and uniformity.

• Housing: Lightweight extruded aluminum is commonly used for the housing to help with durability and controlling the weight of the luminaire.

• Finishes: Like most commercial ceiling luminaires, the common finish is matte white and can be specified without VOCs or any toxic heavy metals.

Since some aspects of products vary between manufacturers, using the component specifications above will aid in product to product comparisons during design and assure appropriate installations during construction.

Part 3 Execution

Providing and installing LED panel luminaires is also similar to other luminaires.

• Examination and preparation: The ceiling needs to be ready to receive the luminaires and the wiring runs need to be installed which all speak to proper project coordination during construction. If integration into a larger building management system or lighting control system is part of the project, then that coordination needs to be done ahead of time as appropriate.

• Installation: Typically, installation is intentionally straightforward following manufacturer's installation instructions and electric code requirements.

• Cleaning and protection: Since these are light-emitting panels, the cleanliness during construction and installation is important. Removing dirt, fingerprints, etc. can commonly be done with a non-abrasive cleaner.

• Punch list and final inspection: All LED panels should be turned on and off to demonstrate that they work properly including any dimming functions. Light color should also be readily observable for consistency per the specifications.

• Post occupancy: Many green building and sustainability programs look for information following installation for evaluation and validation of the design intent from both an energy usage and environmental quality standpoint. If required, this should be referenced in terms of how the lighting plays into that post-occupancy evaluation and monitoring.

Conclusion

Compared to other lighting choices, LED panel luminaires provide an easy means to dramatically reduce energy consumption in commercial building spaces on the order of 31 to 64 percent. At the same time, the light quality can be specified to meet a range of needs but is generally regarded as very high overall delivering very good light color choices through a unique binning and mixing process. That means that any LED color variation between fixtures is imperceptible to the human eye. When installed in commercial buildings, LED panels can provide smooth and uniform light from edge-to-edge for a clean, modern look when recessed in suspended ceilings or surface mounted to other ceilings. In addition to energy cost savings, their very long service life saves notably on maintenance and lamp replacement costs. And with utility rebates available up to $100 per fixture, they are even more cost effective when included in new or existing building projects. All of these attractive and desirable attributes have allowed this LED panel technology to be among the fastest growing luminaire types available today. They should clearly be considered for current and future commercial projects.

Peter J. Arsenault, FAIA, NCARB, LEED AP, is a nationally known architect, sustainability consultant, technical writer, and continuing education presenter. www.linkedin.com/in/pjaarch

RAB Lighting is committed to creating high-quality, affordable, well-designed, energy-efficient LED lighting and controls that make it easy for distributors to sell, electricians to install, and end-users to save energy. RAB’s LPANEL™ delivers ultra smooth edge-to-edge light in a modern design and breaks new ground in efficiency, delivering up to 106 lm/W. Request a free sample of the 2x2 panel and see for yourself. www.RABLED.com