Tubular light-emitting diode (TLED) lamps can be easy to install, offer longer life, and reduce energy usage compared to fluorescent lighting, but there are seven things you should keep in mind when considering a TLED retrofit.
1. TLEDs can help save energy, but there are tradeoffs.
These tradeoffs especially appear when dimming ballasts and a control system are already in place. If the lighting needs to provide smooth, high-performance, flicker-free dimming, TLEDs may not be able to deliver these benefits.
2. There are 3 different scenarios for LED retrofits
Scenario 1: TLEDs retrofitted with existing fluorescent ballasts (UL Type A).
Fluorescent lamps are replaced with specialized LED lamps that simulate fluorescent lamps and work with the existing fluorescent ballasts.
- Benefits: minimum labor and no modification to existing wiring or sockets.
- Potential Risks: ballast compatibility issues, poor dimming performance, and higher cost.
Scenario 2: TLEDs wired directly to line voltage (UL Type B).
This retrofit requires very little rewiring and uses only one component—a TLED with an integrated line voltage driver.
- Benefits: Easy to install.
- Potential Risks: Increased labor costs if wiring and existing sockets need to be replaced. Also, a future installer may unknowingly overload the lamp with a fluorescent bulb.
Scenario 3: TLEDs supplied with dedicated LED Drivers (UL Type C).
This option involves removing the existing lamps and ballast, wiring in new LED drivers and installing TLED lamps in the existing sockets.
- Benefits: Certified, reliable solution, warrantied performance. Compatibility can be confirmed in advance.
- Potential Risks: If existing control wires are not already run to the fixture, adding a dimmable LED driver may require a wireless interface or additional wiring.
3. System efficiency can vary.
In Scenario 1, the ballast must convert line voltage to a regulated current and voltage. The lamp’s electronics must reregulate the current and voltage specifically for the TLEDs, potentially resulting in lower system efficiency compared to other scenarios.
4. Product lifetime can be an issue when using existing ballasts.
In many Scenario 1 situations, if the ballast is not replaced when the TLED is installed, you may not get the full, long-life benefit of the TLED lamp.
5. For best TLED dimming performance, replace the existing ballasts with an LED driver.
TLEDs can significantly alter the amount of light in a space, possibly leading to uneven light levels, different distribution patterns and even glare. Using the appropriate LED driver may mitigate these factors and increase energy savings.
6. Not all LED dimming options are created equal.
Optimal dimming performance can only be achieved by properly pairing LED drivers and TLED lamps with the right controls (as in Scenario 3).
7. Choosing a TLED retrofit solution is a careful balance—ease of installation versus cost versus performance.
For optimal performance and the highest level of safety, use a pre-certified solution consisting of a dedicated LED driver with low-voltage TLED tubes (Scenario 3).
For more complete information about TLED Retrofits, read, “TLED Lighting Scenarios for Retrofit Applications”.
Notes
U.S. Department of Energy CALiPER Report 21.2, “Linear (T8) LED Lamp Performance in Five Types of Recessed Troffers”
U.S. Department of Energy SSL Technology Fact Sheet, “Upgrading Troffer Luminaires to LED”