Updated 10/13/23 by Angela Rogers

Are you considering retrofitting your fluorescent light fixture to accept LED tube lights? Retrofitting existing fluorescent lights offers a wide range of benefits, including increased energy savings and reduces maintenance costs. One of the most popular options to retrofit light fixtures with is with ballast bypass (Type B) tubes. These LED tubes require that the fixture's ballast be removed, or bypassed. The fixture is then rewired so that the tubes run solely off of the line voltage.

While the process of bypassing or removing a ballast from the power circuit to install LED lamps can be quite straightforward, it is crucial to be aware of the potential challenges that can arise during a renovation. In this post, we'll show you the step-by-step process to retrofit a typical fluorescent fixture with ballast bypass tubes.

Warning Before You Start

If you browse the available ballast bypass lamp options available on our website, you will see some some variation of this warning: “Ballast bypass installation required. To be installed by a licensed electrician only.”

These warnings are there for good reason, as there are many risks when working with electrical equipment. Therefore, we urge you to carefully read the following warning before proceeding any further:

"If you do not possess the necessary expertise to safely and correctly install electrical equipment, we strongly recommend that you seek the services of a professional electrician before proceeding with your reconstruction."

Ballast Bypass - Step-by-Step Guide

We are now ready to begin. Please keep in mind the these instructions don't cover all details or variations in light fixtures. They also do not cover every possible instance that may occur during installation. If you have any questions, are unsure about any of the steps below, or come across something that looks even remotely unusual in your fixture, immediately call a licensed electrician.

We also strongly recommend that you read through these steps multiple times to ensure you have a full understanding of them.

The following steps cover bypassing a common electronic ballast, which is typically used with T8 fluorescent tubes. The fixture will then be rewired to accept single-ended T8 LED tubes using non-shunted sockets.

Step 1: Turn off the power.

Begin by turning off the power. Simply flipping the light switch to the "off" position does not guarantee that the flow of electricity has ceased. It is essential to locate the breaker box and identify the breaker switch that controls the power in the area.

Turn off this breaker switch. By doing so, you will prevent any accidental power activation by small children, well-meaning neighbors, or even potential adversaries while you are rerouting the wires.

Step 2: Locate your ballast.

In many T8 fixtures, the ballast is covered by a casing and located underneath the T8 tubes, meaning you need to remove the tubes and unscrew the casing to get to the ballast. Remove any covers, cases, lenses, or lamps that block access to the ballast and set them aside.

If your fixture has a magnetic ballast, you will need to locate the separate starter device and disconnect it as well.

Step 3: Disconnect the hot and neutral wires.

A hot wire carries the power to the fixture. It is typically covered in black or red, meaning “hot” or “live”. A neutral wire (for the sake of simplicity) is a white wire which completes the circuit back to the electrical panel.

In any case, once you identify the hot wire, the neutral will be on the same side. You need to cut these wires close to the ballast.

Step 4. Disconnect the socket lead wires.

The socket lead wires (most likely red, blue, or yellow-colored wires) exit the ballast and connect to the sockets. Please note that singles-ended LED T8 tubes require non-shunted sockets. These output wires provide power to the lamps. You will also need to cut any wires leading to the second set of sockets. You only need one set of sockets, on one side for single-ended tubes, to wire the main power.

Let's pause for a brief summary of steps 3 and 4: Cut all the wires that are keeping the ballast in the fixture within 2 inches of length.

Step 5. Remove the ballast.

Now that you have severed the wires that create the circuit through the ballast, you can unscrew the ballast and physically remove it. Curl up the remaining shorter ballast wires and tuck them away.

Step 6. Connect the input wires to the output wires. 

Strip about one inch of the colored insulation off of all the remaining wires. The input hot and neutral wires (black and white) coming from the building need to be connected to the output hot and neutral wires coming from the sockets.

Connect the hot and neutral wires from the building to the sockets so that one pin is hot and the other is neutral. This connection can be achieved using push-in connectors or wire nuts that screw on to complete the circuit of power.

It is important to note that single-ended T8 LED tubes only need power on one end. Fixtures with multiple lights may have more than one set of wires on one end of the ballast. You only need to connect the input wires to one set of output hot and neutral wires.

Exercise Caution When Bypassing a Ballast

Congratulations! You have successfully removed the ballast from your fixture. As stated earlier, we strongly recommend that you read though this several times to familiarize and understand these steps.

If you are still confused after reading this article, we strongly advise you to contact an electrician. Furthermore, if you have any doubts about whether your wiring setup aligns with these instructions, it is best to consult an electrician. Whenever in doubt, hesitant, or simply not in the mood to climb a ladder today, it is always a wise decision to call a professionally licensed electrician.

Selecting the optimal retrofit LED can be overwhelming, as there are various options available. It is worth noting that some retrofit LEDs, such as plug and play tubes, can be installed without having to bypass the ballast. To delve deeper into the types of retrofitted LEDs, we encourage you to read our informative post Eureka! A Road Map to Retrofitted Fixtures.

Have More Retrofit Questions? 1000bulbs.com Can Help

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