Field-adjustable—also called field-selectable—lamps and luminaires allow performance to be dialed in the field, either prior to installation or during routine maintenance as space needs change. For electrical contractors, these lighting products can simplify job site planning, act as insurance against change orders and provide the basis for future service.

The last time I covered this technology in 2022, it was relatively new. Since then, field-­adjustability has grown to cover most lighting product types—from troffers and panels to high-bays to outdoor area lighting—with products widely available.

Essentially, these products are staple lamps and luminaires, with an added feature enabling certain performance parameters to be adjusted in the field. This is ideal for when the customer is not sure what they want or for when they change their mind. In such projects, the contractor can work directly with the customer to produce the optimal environment.

What can these products do?

For indoor lighting, this typically involves light output or both light output and correlated color temperature (CCT), though some products also offer selection of light distribution and beam angle. For outdoor lighting, it typically involves light output but may include other parameters such as CCT. These are typical factory-preset options.

For example, a field-adjustable LED troffer may be available with an offering of low (3,350 lumens), medium (3,850 lumens) or high (4,350 lumens) light output and associated wattages and a choice of 3,500K, 4,000K and 5,000K CCTs. This enables the same lighting product to perform service in a broader range of applications.

The adjustment mechanism can be fairly simple. A common method involves mechanical dip switches or knobs wired to the driver or part of it. These controls set the driver to draw varying levels of current based on the desired light output and, when applicable for CCT selection, adjust power between warm and cool LED arrays. Luminaires are typically set once and then installed, though after installation they can be reset (with the power off for safety) any time as space needs change.

While this is the most common method for adjusting the luminaire, new products increasingly feature wireless or app-based interfaces using Bluetooth or some other near-field communication. Yet another method is to remotely program the luminaires using a lighting control system.

These lighting products involve a small premium for their additional engineering since they are not a one-size-fits-all solution. However, in projects where the lighting is precisely specified, their usefulness diminishes, because the designer knows exactly what is needed in terms of lighting performance.

In retrofits, fast-tracked projects, multi-use facilities, spaces where lighting needs may change over time or where some on-site customization may be needed, however, field-adjustable lighting can pull its weight. In such projects, the contractor may wind up in a situation where precision occurs at the job site and not much before beyond knowing the type of luminaire required.

In these situations, field-adjustable lighting products can entail less back and forth, fewer availability issues and reduced risk of being called back. In retrofit projects where the application has a lot of variability in space types and ceiling heights, field-­adjustable lighting can mitigate a less precise audit. As long as the right luminaire type is delivered in the right quantity, light output and CCT can be tuned on the spot to create an optimal environment.

When field-adjustable lighting is used, a little more time may be needed with the customer during installation to come to the right settings, but overall, service efficiency may be enhanced by leaving a satisfied customer. The customer gains a lighting system whose performance they have some control over by seeing options in the actual space prior to full-scale installation, and they also gain the ability to adjust the lighting system to accommodate space changes later, either using the maintenance personnel or by calling their favored contractor.

Rebates

Note that for retrofit projects, field-­adjustable luminaires are typically recognized by commercial lighting rebate programs offered by utilities and energy efficiency organizations. The DesignLights Consortium (DLC) recognizes field-adjustable luminaires in its Qualified Products List, which many rebate programs use to qualify LED products for rebate eligibility. 

The DLC’s Version 6 Technical Requirements for solid-state lighting products revised its requirements for field-adjustable LED lighting to provide more comprehensive reporting, offering the industry more information and allowing energy efficiency programs to verify performance.

However, there is some variability in how these programs treat field-adjustable lighting. Some may recognize only the DLC-listed wattage—the maximum wattage among the choice of light outputs—while others may recognize a lower wattage that is installed, based on some type of verification. In retrofit projects involving a rebate, it can be helpful to confirm whether it applies to field-adjustable lighting, as well as any specific requirements.

Overall, field-adjustable lighting can provide more flexibility for installation, which for some projects can improve service quality and efficiency.

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