fluorescent ballasts


Old 03-09-08, 11:17 AM
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fluorescent ballasts

I recently had to check a bunch of fluorescent fixtures that had burned out bulbs and found that many of the ballasts seem to be the problem. I know the basics of how ballasts work, but my main question is this; what is the melted, black goo oozing out from seams on the ballasts? If there is juice getting to the ballasts, but seems to be minimal/none coming from them (through the blue and red wires) does this pretty much mean the ballasts are shot, or are there other things going on? Thank you all for any input!
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Old 03-09-08, 11:49 AM
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The black goo is the insulating material that the ballasts are surrounded by. (It called "potted") This is a sure sign of over heating. If you took off the metal case of a good ballast you would see what looks like a black brick of tar. The actual ballast is in that.
Old 03-09-08, 12:13 PM
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It is basically tar. When the ballast overheats it melts and comes out. I think it is partly there to quiet the noise. It is only in magnetic ballasts. You won't find in the newer electronic ballasts.

No point in measuring voltages on ballasts. Change the tubes. If they don't come on, change the ballast.
Old 03-09-08, 12:34 PM
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if there is black goo oozing out, don't even bother with trying the lamps though. Replace the ballast and I replace the lamps as well. They are quite inexpensive (in the over all picture of life) and a bad ballast can make lamps burn out prematurely so unless the lamps are relatively new, they get changed as well.
Old 03-09-08, 03:52 PM
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Old ballasts contain PCB's too (or a replacement that is almost as bad). It is oily and can drip from the ballasts.

Once a ballast starts leaking PCB's, it must be disposed of as hazardous waste.

I'm not saying this is happening in your case, but if the ballast is really old it is probably worth getting rid of it before a haz-mat team is dispatched.

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