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What is a fluorescent light ballast? What you need to know.

Every now and again I get calls from people who are trying to get their fluorescent lights working again. And for those people who don't have any experience in how these work, they either don't know that it has a ballast or they think it's a transformer. A ballast is not a transformer, a transformer simply takes one voltage to another. A fluorescent ballast is made to start the arc across the fluorescent tube at a higher voltage and then reduces to a lower voltage for general operation of the bulb. There's really nothing more to it than that. And this is the reason there are many types of ballasts for many different types of lamps. They're not all the same electrically and require different starting and operating voltages. There are some differences beyond that, some of the older style lamps still operate on magnetic ballasts while the newer ones operate on electronic ballasts. Electronic ballasts are made for lamps that started with the T8 and continue on through the T5 types. They last a lot longer in the field and they deliver a smoother start so that the lamps last longer as well. Most fluorescent ballasts have a five-year warranty against any defects or short life. Magnetic ballasts typically operated T12 lamps which are the older style bulb used in offices for decades. Many people have retrofitted those to more efficient sources by replacing the lamps and ballast. For those of you who still have T12 lamps, you can still get an electronic ballast for those instead of the old magnetic type. Like every industry, the lighting industry has gone through many changes even though it seems to be late upgrading to modern electronics. That could be because some of the legacy lamps have not totally gone away. That's changing and so is ballast technology. Even something as small as getting the right voltage, whether it's 120 or 277 volt was a big deal in the past. You had to make sure you had the right voltage dedicated for that system. Today, you don't have to think twice about it as most electronic ballasts can either be fed by 120 or 277 volt in the same ballast. I know that seems like no big deal but even something like that makes it easier for everyone. So if you have bulbs that have gone out in a group or if the bulbs are flickering a lot and barely lighting at start up, then you probably need to replace the ballast. Most fluorescent fixtures have the ballast located in a channel and all you need to do is remove it to expose the ballast and replace it with a new one. It's an invisible part for lighting, but it's essential for all fluorescent lighting to have a reliable ballast system.

I hope that answers your question, let us know if there's anything else we can help you with.

John Bolduan

Here's the light bulb products I mentioned in this article:

Displaying products 1 - 3 of 3 results
F40T12 ballast - 1 or 2 lamp
F40T12 Ballast - 1 or 2 Lamp
Price Each: $19.00
F40T12 Ballast - 1 or 2 Lamp spacer
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