Below is my contribution to the March 2022 issue of tED Magazine, the official publication of the NAED. Reprinted with permission.

Field-adjustable (aka field-selectable) lighting is LED light fixtures and lamps that allow field selection of preset operating parameters such as light output and correlated color temperature (CCT). For the electrical distributor, they offer a means to consolidate inventory and more flexibly satisfy local demand for lighting products.

On the luminaire side, adjustability started with lower-wattage products such as downlights, troffers, and panels and has since moved into other categories including high-bays and undercabinet luminaires. While predominant for indoor lighting, the adjustability trend has begun to enter outdoor categories such as floodlights, wall packs, and area lighting.

“Field adjustability is an emerging trend across most categories,” said Ross Barna, Chief Executive Officer of RAB Lighting, Inc. “While still not in the majority of lighting products sold today, I would not be surprised to see field-adjustable features in the majority of products within the next couple years.”

“The demand for field-adjustable luminaires continues to grow as distributors are maximizing limited warehouse space,” said Eric Jerger, VP, and GM, Indoor Lighting, Cooper Lighting Solutions. “Field-selectable luminaires offer multiple products in one, saving distributors money by stocking less inventory while still being able to meet the needs of their customers.”

How it works

The lighting product is functionally the same as a static-output luminaire or lamp but with a mechanism allowing adjustability of the light emission. For indoor lighting, this predominantly entailed ability to select light output, which has since evolved to include CCT. For outdoor and high-bay indoor lighting, it predominantly involves adjustability of light output. Other adjustability may be available, such as light distribution (e.g., a troffer with a choice of three reflectors) and ability to turn an outdoor photocell On/Off.

The most common adjustment mechanism is a set of mechanical switches or knobs integral to the driver or wired to it, which offer various output levels based on several labeled factory-preset steps. These manual controls cause the driver to draw more or less current based on the desired light output and manage the power between warm/cool LED arrays to tune color output. In the case of luminaires, they are typically set once and then installed. Some smart products can be controlled wirelessly using an app on a smartphone or using a lighting control system, allowing relatively easy, low-labor adjustment at any time to accommodate changing user needs.

Image courtesy of Cooper Lighting Solutions.

“Field-selectable products can be used anywhere,” Jerger said. “Whether it’s a residential homeowner or a schoolteacher in an education environment or a facility manager in a warehouse, field-selectable products are simple for contractors to install while providing long-lasting benefits.”

Distributor benefits

“For the electrical distributor, the main benefits are flexibility and availability,” said Andrew Banovic, Product Director Commercial Indoor Lighting, Acuity Brands Lighting. “Two of the largest investments in the distribution business are inventory and space to store it. Field-adjustable luminaires allow for drastic working-capital reductions, as well as increasing the turns on the SKUs that are being stocked. This also can eliminate a great deal of returns as a good percentage of returns to a distributor are because of lumen output or color changes that are needed.”

While the supply chain math is complex, Banovic offered a simplified evaluation. Acuity has found a combination of light output and CCT adjustment to be most popular, which allows a single adjustable-output luminaire to replace up to nine static-output models that cover most of the configurations needed for a given luminaire type. If three models can be serviced by a single model, a distributor can cut inventory in half without reducing service levels. If replacing nine models, it goes even lower. Banovic compared it to multi- and universal-voltage drivers and ballasts, which caught on quickly and became the new standard.

He offered an example demonstrating the utility of field adjustability. A local distributor stocks 200 static-output luminaires offering a mix of lumen and CCT packages. A customer orders 60 of the luminaire type, not caring about light output or CCT, as long as they match. Unfortunately, the distributor keeps half the units at 3500K and the other half at 4000K, and half at a high and half at a low light output. As a result, the distributor can’t fulfill the order on the spot. If the luminaires were field-adjustable, it could.

Another example is applicable to retrofits. If field-adjustable luminaires are available, a building with multiple space types and ceiling heights would not need a highly precise audit and specification of lumen packages. The contractor would order a large lot of adjustable lay-in luminaires instead of specific lumen packages in precise quantities that may not be in stock.

“Distributors these days are facing a very challenging environment, where supply chains are unreliable and inflationary pressure is pushing costs up across the economy,” Barna pointed out. “Being able to invest in inventory that can hit many birds with one stone is simply the best option to win in today’s market.”

With the added engineering and value, these luminaires may present a cost premium. While their core utility is fairly broad, they may not make as much sense for highly specified projects with comfortable lead times.

One question that will need to be answered in retrofit situations is whether and in what way the product qualifies for utility rebates. The DesignLights Consortium (DLC) allows field-adjustable luminaires in its Qualified Products List, which many rebate programs use to qualify LED products. BriteSwitch, a rebate fulfillment company, said it has not seen any rebate program expressly exclude field-adjustable luminaires. They added, however, that rebate programs vary in how they treat the luminaires, with recognizing only the DLC-listed wattage (maximum wattage), and others recognizing a lower wattage with some means of verification. As a result, it may be beneficial for distributors to confirm how their local programs handle it, select DLC-listed luminaires if required, and, if they’re managing the rebate, to prefile for approval. In 2021, BriteSwitch reported the average rebate for a field-adjustable troffer/panel, downlight, or retrofit kit was $33-34; $120 for a high-bay luminaire; and $91-97 for outdoor wall and pole/arm mount luminaires.

Final word

“Try them,” Banovic advised. “If you haven’t stocked any yet, add a pallet to your warehouse. See how fast it flies off the shelf and how fast you can get on and off job sites. You will never go back.”