Call us

(800) 327-7877

Email us

What is the Difference Between a Single-Ended and Double-Ended LED Tube?

Energy Focus Blog


What does it mean when an LED tube is “single-ended” or “double-ended”? If you’re not in the lighting industry, these terms might be confusing. Energy Focus is here to break these terms down and help explain the differences between them.


Single-Ended LED Lamp

A single-ended LED lamp is a lamp that has the live and neutral pins on the same side of the lamp. This end will be the “Input” end. If the lamp is being installed as a retrofit into a fluorescent fixture, you will need to replace the fluorescent, shunted lampholders (also called tombstones) with non-shunted lampholders on one side of the fixture. Single-ended LED lamps that will be installed by direct-wire do not use a ballast to be operational. If the lamp is being used in a retrofit, the ballast will need to be removed and the lampholders replaced.

A good example of a single-ended LED lamp would be the Energy Focus 500D Series LED tube. The 500D includes circuitry that limits current input and directly connects to the main power, no longer requiring the ballast for normal operation. This results in lower points of failure, removal of unnecessary hardware, and less required energy consumption.

Double-Ended LED Lamp

A double-ended LED lamp is a lamp that has the live and neutral pins on the opposite side of each lamp. Fluorescent lamps are typically double-ended as well, making retrofit applications easier to complete with double-ended LED lamps. Double-ended lamps use shunted lampholders, so that the two contact pins on the live side of the lamp are shorted together, creating no voltage difference between the pins.

The Energy Focus Commercial Double-Ended Ballast Bypass (DEBB) LED tube is a double-ended lamp. The DEBB can be used with shunted or unshunted lampholders. When upgrading to LED lamps, customers have the option to utilize their existing lampholders, helping to reduce the average retrofit installation time. The Commercial DEBB functions without a ballast, minimizing points of failure and requiring less maintenance.

If you are interested in Energy Focus single-ended or double-ended LED tubes, contact us and we will be able to help you find the perfect LED solution for your installation needs.