Ballast Wiring Tips and Tricks

What You'll Need
Electrical tester
Voltage tester
Needle-nose pliers
Wire nuts
Wire splices
Wire crimpers

Ballast wiring can be a bit tricky, but it's not really that difficult to do, if you pay attention. Make sure to test all the components of your florescent light, before you hook up the new ballast. Ballast can be quite expensive, so you want to be certain that it really is the source of the electrical problem in your florescent light fixture.

Ballast Wiring Tips

  • Always make sure the problem is actually your ballast. Check all the other florescent light fixture components, one by one.
  • Make sure the power is off before you do any work. Use the electrical testers to verify this.
  • Ballast gets very hot, so wait a few minutes before you work on florescent light fixtures that have been turned on for a while.
  • Replacement ballast should always match in voltage, wattage and brand. Wrong ballast types can cause fires or shorts.

Buying the Ballast

  • Bring your old ballast into the hardware store when you are ready to purchase a new one. This way, the units can be matched up. Some hardware stores will have a cross reference book that will show you all of the model types of ballasts that will work for your replacement.
  • If you can't remove the ballast just yet, try to write down all of the information on the tag that is attached to the front of the ballast. This information will be needed to make sure the new and old ballast match up.

Ballast Wiring Tricks

  • Pay attention to how your old ballast is wired up. Make a drawing of where each wire goes, before you cut any wires. Also, pay attention to what color each wire is, as same colored wires usually go together, but sometimes they don't.
  • Ballast wires are very small in size, so make sure your wire crimps or wire nuts are sized for small wiring. The same thing goes for any wire nuts used.
  • Make sure and leave enough wire sticking out from each ballast end. This will prevent you from accidentally cutting the wires to short. Or, if you wire something up wrong, you can re-cut and rewire because you still have plenty of ballast wire to work with.
  • Mount the ballast inside the mounting bracket first, then hook up the wires. This way, the heavy weight of the ballast won't be hanging down, possibly loosening up some of the wired connections.
  • Multiple ballast should all be mounted first too. Then just go down the line and hook up one ballast at a time.
  • Wire splices are more secure then wire nuts. If you don't have any experience using the crimping tool, you might want to practice on a few old pieces of wiring so you can get the hang of it. 
  • Always have eye protection in place as well as keeping a fire extinguisher on hand for any emergencies that might occur.

Wiring up a ballast is not that hard to do. With common sense and the right tools, the job can be done safely and correctly.