Shop ceiling light (fluorescent) problem.

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The Artist formerly known as Turbo84
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Clinging to my guns and religion in KCMO.
Gotta a couple questions regarding my shop lights (8' fluorescents). The other day one of the tubes fell down and made a hell of a mess on the floor. Got it cleaned up, and climbed the ladder to the hanging fixture to see wth happened. The tubes are single end-terminals, and the spring loaded ceramic tube that the terminal slides into looks like it got real hot (it's dark brown at the edge which is broken off, which might explain how the tube was allowed to drop) and the spring looks less than shiny. My questions are: What's the usual cause for this heat/discoloring? (And don't be a smartass and tell me it's wattage, Turtle :rolleyes:) I'd like to fix this fixture rather than buy another one, but I've never noticed these ceramic tubes in the electrical section before. I'd thought about replacing this ceramic piece with a short piece of steel tube, but then the heat isn't going to be isolated somewhat from the rest of the support bracketry.

So, do I trash this thing (and put up two 4' pairs instead), or is it repairable?
Thanks,
Mike
 
You can buy new tombstones at most any electrical supply house. Then simply wire nut the matching colored wires together.

As for root cause, dirty tubes or connections will create heat possibly annealing the spring. The burnt area is certainly indicative of that. But where did it start? Weak spring making poor connection? Dirty tube connection generating heat.

Id just replace the tombstones and move on.
 
You can buy new tombstones at most any electrical supply house. Then simply wire nut the matching colored wires together.

As for root cause, dirty tubes or connections will create heat possibly annealing the spring. The burnt area is certainly indicative of that. But where did it start? Weak spring making poor connection? Dirty tube connection generating heat.

Id just replace the tombstones and move on.

I'm not familiar with the tombstone label in this context. Which part in particular does this refer to?

Thanks,
Mike
 
You can buy new tombstones at most any electrical supply house. Then simply wire nut the matching colored wires together.

As for root cause, dirty tubes or connections will create heat possibly annealing the spring. The burnt area is certainly indicative of that. But where did it start? Weak spring making poor connection? Dirty tube connection generating heat.

Id just replace the tombstones and move on.

Bingo....I"d hit them all with a bit of WD40, or at least some electrical contact cleaner, work the bulbs around a bit, and call it a day.....

obviously replace the parts....
 
Must be an old fixture to have ceramic tombstones. All of them are plastic now. They all turn and get brittle with plain old age. There is also the possibility the lamp merely cracked and failed.
BTW, if you change to a 8' 4x2 lamp fixture using slim T-8 type lamps, it will draw less than 50% power of that old "slimline" fixture.
 
Must be an old fixture to have ceramic tombstones. All of them are plastic now. They all turn and get brittle with plain old age. There is also the possibility the lamp merely cracked and failed.
BTW, if you change to a 8' 4x2 lamp fixture using slim T-8 type lamps, it will draw less than 50% power of that old "slimline" fixture.

Ya lost me on the 4x2 description. Does this have two 4' bulbs in the 8' length, with a total of four 4' tubes/lamps under the reflector? Or ?
 
Does this have two 4' bulbs in the 8' length, with a total of four 4' tubes/lamps under the reflector? Or ?

Yes sir.
The T-8 lamps have a slimmer tube, yet contain more phosphorous, yielding more lumens per watt. They also operate at higher frequencies, therefore less noise, and faster starting. They will require a short duration to reach full intesity per temp drop below ambient.
 
You might be able to convert your existing fixtures to T8 style by replacing the ballast along with repairing the broken parts. I've converted older fixtures but never one with the ceramic ends so not sure how that would work out.

DC
 
Strange, in that I dunno I ever posted about this or not, but last spring I had a 3X recall on some kitchen ceiling 4' recessed fixtures....two double bulb florescents.... so during this process we had the power company check the lines out for proper whatever, looks fine on my DVM....

so I go out and replace 4 bulbs, a month later replace 4 bulbs and two ballast transformers ......

a month or two later replace two totally NEW fixtures with the new energy saver types, and the thin T8 bulbs as mentioned above 32 watts each as I remember...green ends....so now the entire damn thing is NEW....wiring checks out totally kosher....

a month later we go out with two incandescent ceiling fixtures and 4 60 watt bulbs, she says too dim, I say pull off the lens covers and replace one of the bulbs in each with a 100 watt bulb, but to never use a CFL....

heard nothing since.....so go figger....

anyone with ANY clue why??....


:crap::crutches::huh2:
 
Strange, in that I dunno I ever posted about this or not, but last spring I had a 3X recall on some kitchen ceiling 4' recessed fixtures....two double bulb florescents.... so during this process we had the power company check the lines out for proper whatever, looks fine on my DVM....

so I go out and replace 4 bulbs, a month later replace 4 bulbs and two ballast transformers ......

a month or two later replace two totally NEW fixtures with the new energy saver types, and the thin T8 bulbs as mentioned above 32 watts each as I remember...green ends....so now the entire damn thing is NEW....wiring checks out totally kosher....

a month later we go out with two incandescent ceiling fixtures and 4 60 watt bulbs, she says too dim, I say pull off the lens covers and replace one of the bulbs in each with a 100 watt bulb, but to never use a CFL....

heard nothing since.....so go figger....

anyone with ANY clue why??....


:crap::crutches::huh2:

99% of the time, it's a bad/loose/poorly grounded nuetral wire.
 
(And don't be a smartass and tell me it's wattage, Turtle :rolleyes:)
Thanks,
Mike

Go ahead and deny me my fun.

How about a mechanical engineering approach.

I'd wrap the light housing with duct tape kinda like a drive shaft loop for your light sticks.

Use your IR gun to see how hot those connections and transformer are getting. I'd throw it out if its getting more than 120 degrees F.
 
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NOW LOOK WHAT YOU STARTED BIRD

He should just go to hd or lowels and get a new t 8 fixture ( less work and the cost of a ballast and end caps will be more then a new fixture) And less work.
 
Must be an old fixture to have ceramic tombstones. All of them are plastic now. They all turn and get brittle with plain old age. There is also the possibility the lamp merely cracked and failed.
BTW, if you change to a 8' 4x2 lamp fixture using slim T-8 type lamps, it will draw less than 50% power of that old "slimline" fixture.
Thanks for the tip Bird; I'm picking 4 fixtures up at Home Depot tomorrow. :thumbs:
 
Got a replacement piece at Lowes and got it installed and wired up yesterday. Darn thing works, so I'm happy. I need to add another 8' fixture at the back of the garage, so I'll look for that setup you mentioned, Bird.

Thanks, guys!
 
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