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Discussion Starter · #1 ·
I"m having an issue with kitchen lights. I'm in an apartment unit that used a light fixture with 2 t8 flourescnet bulbs (with electronic intant start ballast). I want to replace them with led bulbs. I removed the ballast and direct wired the tombstones (shunted), and the lights arn't coming on.

Heres the bulb im trying to install

heres the bulbs currently in the fixture:

https://www.amazon.com/Sylvania-21777-FO32-830-ECO/dp/B07R623YPK

attached is the direct wire config: 2 Blue wires on hot (black) one red wire on neutral (white)
the tombstones, being shunted, and 1 blue wire coming from each Left tombstone, whereas the right side has a red wire coming from one tombstone, but a blue with black striped wire connecting the 2.
 

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It looks like you have it wired correctly. Have you tried flipping the tube from one end to the other? Sometimes the manufacturers only attach the input to one pin on the tube. That combined with the possibility someone replaced the original tombstones with a non-shunted might be your problem.

After that, if you have a meter, check for 120V across the socket. Might have a bad socket or a bad connection in that box buried behind the fixture.
 

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Looking at your photo the wiring looks fine. Unless you did a fantastically awful job of wire-nutting, I simply cannot see how you could have done it wrong.

We can cross off "broken tombstone" since it would take 2 of them to cause a total fail. All that remains is that your power supply isn't actually supplying power.

Well, one more thing.

LED fluorescent tube replacements are a "gold rush" with every shady company in China piling onto the "crank out this crud" bandwagon... and so there's a lot of junk-ola out there. I've seen tubes marketed as double-ended, but when you actually open up the box, it's single-ended because hey, those are a penny cheaper. My browser shows me (in green) the company name on the security certificate, take a look.

648472
 

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Discussion Starter · #4 ·
Trying different combinations of ends and such proved no avail.
in the case of "Is it acually a single ended?" i noticed the end of the tube does not have a L & N on the ends. I think if it was single ended it would.
It is possible the tubes suck.
One thing i forgot to mention, after wiring everything and inserting both tubes, they acually came on and stayed on for like...15 seconds? then got really dim, flickered, then died, and i could NEVER get them to come back on.
 

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Discussion Starter · #5 ·
Also pointing out I'm in an apartment unit, so i dont think its a power supply or bad connection.
 

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Wait, they both worked and then failed together? You plainly did not wire the lamps in series. Cheap Chinese fails, but it doesn't do synchronized failing. This looks more like a supply failure, somewhere between the tombstone the shared red wire is going into, and the service panel.

"Once you eliminate the impossible, the improbable, however unlikely, must be the truth" - Arthur Conan Doyle

I'm certainly glad you are using double-ended tubes here. If you used a single-ended and the landlord or the next tenant put a real fluorescent in the fixture, the preheat filament would get hotshot 120V. Likely to explode with a spray of broken glass, phosphors and mercury.
 

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Discussion Starter · #7 ·
my thought exacally on the single ended issue.
But yeah ofc the flourescents worked, i took them out, removed the ballast, rewired, put in the LED's, turned it on and thought wow they work i didnt expect them too! Then they shorted out.
 

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Discussion Starter · #8 ·
I'm kinda "new" to electrical related issues, so any advice on what you guy's would do in this situation is very much appreciated.
 

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Do you have a meter? Check for power.

If not, and you feel comfortable doing so, use a cheater cord to power the tubes directly and plug it in to a known working outlet.
 

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Discussion Starter · #10 ·
I actually have an extreme phobia of electricity due to being horribly electrocuted as a kid, so meter it is! lol. Where should I test with the meter? the metal bits in the tombstones? or the hot wire?
 

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Start with the tombstone contacts. if that fails check between the hot and neutral wires, possible to have a bad tombstone connection.
 

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I'm certainly glad you are using double-ended tubes here. If you used a single-ended and the landlord or the next tenant put a real fluorescent in the fixture, the preheat filament would get hotshot 120V. Likely to explode with a spray of broken glass, phosphors and mercury.
Well of course if he had installed single ended, cutting those wires to the other end would have been part of the install. I just installed single ended myself, and leaving those disconnected was clearly illustrated in the instructions. (It also came with a sticker that said the fixture had been converted, but I don't count that as a real safeguard.)
 

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Well of course if he had installed single ended, cutting those wires to the other end would have been part of the install. I just installed single ended myself, and leaving those disconnected was clearly illustrated in the instructions. (It also came with a sticker that said the fixture had been converted, but I don't count that as a real safeguard.)
How would that help? We're talking about 4-pin fluorescent tubes. Think about what is between the 2 pins on each end of a tube.

It's an electrode, but it doesn't need 2 pins for that.

It's also a preheat filament. Sort of like an incandescent filament but it's only ever made to glow orange. They're sized to be in series with each other and the ballast and the starter. Sometime I'll try with an old tube and see what happens if you hotshot 120V onto the filament, but I'll be some distance away lol.
 

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I suspect nothing would happen except the filament would glow. They are tungsten filaments. I just measured 8Ω cold resistance on a T8 tube, not much less than the cold resistance of a 100w incandescent lamp. Even if it were to pop, I don't think it would be anything spectacular.
 

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Hrm, the little bayonet parking lamps in my car have more than 8 ohms cold resistance. That doesn't mean it's OK to put 120V on them.
 

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Discussion Starter · #19 ·
Alright, sorry it took me so long. After messing with the ole' Multimeter, I checked the main hot and neutral to the fixture (not the tombstones) and it read about 120v AC (its analogue, so numbers are approx.)
then I check the tombstone contacts, zero. Then maybe the wires coming from them? one lead on half the fixture and another on the other half? I tried many different combinations here, all read zero. Now this could either be because of comically terrible wire nutting, OR the main power isn't getting to the tombstones. Let's assume it's the ladder; what would one do about this?
 

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How would that help? We're talking about 4-pin fluorescent tubes. Think about what is between the 2 pins on each end of a tube.
What do you mean how would it help? You're the one who said if they left them connected it would fry a fluorescent bulb. It doesn't "help" anything, it just avoids having electricity where you don't need it. With a single ended LED those 2 pins are just for support so they don't need to be connected. If someone tried to install a fluorescent bulb, you don't want them connected.
 
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