As a follow-on question to: Why fluorescent lighting tombstones melt? I do not know what caused a massive current to melt the tombstone: was it the ballast?

The MELTED tombstone will be replaced, however, if after the tombstone is replaced AND the installed ballast lights up a new bulb: what is the decision process to determine if the ballast should be replaced?

If it was the ballast, then it would be ideal if it would disqualify itself by simply failing to start bulbs. At worst it would continue to start bulbs and melt tombstones.

If the ballast is the root cause of the ballast, then shouldn't it be replaced? If this is the correct question to ask, how does one go about determining if the ballast is NOT the root cause?

If it is not the right question, then I would appreciate the experience of the community weighing-in.

  • Since you have to replace the tombstones anyway you should just get direct wire LED tubes, No ballast required. Get un-shunted tombstones. Save money with LED and by not powering a ballast.
    – Alaska Man
    Commented Mar 4, 2019 at 17:42

1 Answer 1


First I check for obvious fitment of the tubes and conditions of the tombstones. For instance one easy problem is failing to rotate the tube a full 90 degrees, so it doesn't properly engage. On T8/T12 tubes there are score marks to help tell you where center is. Can't speak to T5.

If that all checks out, and fitting new lamps doesn't make them all light, or if the ballast has a rep for burning up lights quickly, or is leaking goop, smelly or buzzing loudly, then I condemn it by snipping all its wires flush at the ballast. That assures no one wastes time trying to reuse it.

Otherwise if it is a magnetic ballast, I cut or unhook its wires in a non-destructive way, and stick it on the shelf as a usable T12 ballast (I only fit new T8 ballasts). That happens when I upgrade a 2-ballast fixture.

Then I slap in whichever electronic ballast I please to, with a strong preference for rapid start or programmed start ballasts. If a fixture had a serious arcing problem, I would shun the arcey instant-start ballasts, and favor programmed-start ballasts as they have a startup sequence.

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