What follows are highlights excerpted from the white paper LED Retrofit Options For Linear Fluorescent Luminaires, produced by the California Lighting Technology Center at the University of California, Davis.
“Fluorescent lamps currently dominate the commercial sector, where they account for 80% of installed lamps. LED alternatives to fluorescent lighting products currently fall into three main categories: tubular lamps, retrofit kits, and dedicated luminaires. These LED replacement options require varying amounts of labor to install, entail different costs, and require different safety precautions.”
For our purposes we’re going to examine tubular lamps and retrofit kits, which almost always represent the most economical approach when compared to new luminaires.
Tubular LED Lamps
“Replacing existing linear fluorescent lamps with similarly shaped LED lamps requires minimal new hardware, but this strategy presents some unique challenges that should be understood thoroughly before purchase or installation.”
“The electrical incompatibilities between linear fluorescent and linear LED lamps constitute the most important safety issue facing tubular LED technology. ‘Drop-in’ tubular replacement lamps often incorporate a driver inside the lamp. With these products the existing fluorescent ballast is utilized, and the tubular LED bi-pins connect directly to the existing lamp holders or ‘tombstones’. Thermal build-up inside the tube with this technology can compromise lamp life when driver components are exposed to higher temperatures. The form factor of the linear tube presents constraints on thermal management.”
“The fact that many LED replacement lamps connect through the bi-pin tombstone, even when a new LED driver is installed in place of the ballast, can create confusion for future maintenance workers who might attempt to replace lamps with a traditional fluorescent lamp.”
LED Retrofit Kits
“An LED retrofit kit provides the required electrical components, optical elements and light sources in a prepackaged kit. This replacement option provides a repeatable, efficient retrofit solution for the majority of troffers in today’s building stock.”
“Retrofit kits…often provide better light distribution than tubular LED replacement lamps because they are able to better integrate the LED sources with the structure of the troffer and optical elements.”
“…LED retrofit kits utilize the optical reflector and mechanical elements as thermal conductors. The inherent differences in mechanical architectures place the retrofit kit at an advantage when it comes to thermal management.”
The John Riley Group uses only LED retrofit kits when upgrading fluorescent fixtures.