How to Install Ballast for T8 Fluorescent Lights

Fluorescent lights require a steady stream of correctly modulated power to operate. That's why they have ballasts -- small electronic devices that provide the steady power the lights need to operate. Ballasts are classified according to their power output and the type of tubes with which they'll be paired. If your fluorescent tubes are flickering on and off, it's usually a sign of a bad ballast. The T8 ballast is one of several types of ballasts commonly employed with fluorescent tube fixtures and can be replaced if the original is no longer functioning.

Flat-head or Phillips screwdriver
Wire cutters/strippers
Wire nuts
Electrical tape

Instructions

- 1
  Turn off the power leading to the fluorescent light fixture at the circuit breaker panel.
- 2
  Remove the fluorescent tubes from the lighting fixture by rotating them until the pins at the ends are loose and the tube slides out of the socket.
- 3
  Loosen the flat-head or Phillips head screws on either end of the black rectangular ballast box located on one end of the light fixture.
- 4
  Lower the ballast from the fixture. Cut the wires of the ballast about 1 inch from the end of the ballast. Since there's no power going to the light, there's no concern for electrical shock.
- 5
  Remove 1/2 inch of insulation from the ends of the cut wires with wire strippers.
- 6
  Match by color the bare ends of the new ballast's wires to the wires you've just stripped. Slide a wire nut over the ends of each bare wire pair.
- 7
  Twist the wire nuts until they're tightly fastened onto the wires. Wrap a piece of electrical tape around the base of each wire nut.
- 8
  Place the ballast into the light fixture. Attach it to the fixture with the screws.
- 9
  Put the fluorescent tubes into the sockets. Turn the power back on to operate the light.

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