LED replacement bulbs don't work in a fluorescent lamp

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Hello all, hoping as usual you all can provide some wise technical advice. I have a SAD* light which uses three fluorescent bulbs. The bulbs are oddballs, 2G10 type. The light seemed dimmer than usual (it used to be quite bright) and when I opened it up, one of the three bulbs was burnt out. Rather than replace it with another fluorescent, I figured I'd switch over to LED. The 2G10 bulbs are rare, and I couldn't get one locally, but did find them online. (* The SAD light is used to treat Seasonal Affective Disorder, which is essentially poor mood due to lack of sunlight, unfortunately quite common here during our long dark northern winter.) Received them today, installed them, and fired up the lamp with the cover off (seven screws to remove the translucent cover, so wanted to make sure I had the bulbs seated correctly). The three new bulbs looked great. So I put the cover back on, and none of the three bulbs would light. Wha ...??? Took the cover off again and tried substituting in the two good fluorescent bulbs. They worked fine, but I could not get more than a flicker out of and of the LED bulbs. There was a mild but definite smell of hot electronics. I wondered if I'd smoked something in either the lamp or the new LED bulbs. Took the plastic covers off of one of the bulbs and tried to probe the internal wiring to see if the bulb was getting voltage. Strangely enough, touching any one of six of the eight contact points (there are four "tubes", each with a + and a -) with one probe only caused the LEDs to illuminate. I tried this again with the DMM turned right off, and it still worked. I figured I was adding some capacitance to the circuit. Then I exposed the guts of the lamp. There are three circuit boards, one for each bulb, each including a transformer, several power transistors, and inductor, and a bunch of capacitors. I figure this circuitry is all in aid of running the fluorescent bulbs. Furthermore, the tantalum caps look to be darkened - they don't look healthy. I'm wondering whether the LED bulbs (rated at 15 W each) somehow damaged the circuitry (designed for fluorescents, rated at 36 W each). [P = IV. I = P/V. I = 15 W/120 V = 0.125 A. I = 36 W/120 V = 0.3 A. On this basis, it's not like the LED bulbs would draw too much current. Perhaps not enough?] Given that the LED bulbs are rated for an input of 100 - 277 VAC, I am tempted to bypass the fluorescent circuit boards, wiring the 120 VAC inputs directly to the receptacles for the LED bulbs. (I would keep the ON/OFF switch in the circuit of course.) There's a simple diagram on each of the LED bulb assemblies, showing an input of 100 - 277 VAC across the L and N terminals. Does anyone see a downside to this? At this point I could put the two working fluorescent bulbs back in, and run the lamp until they give out, and eat the cost of the new LED bulbs. But at some point they'll give out as well. It might be possible to get new fluorescent bulbs though. But once I start modifying the lamp, it will be hard to go back. Perhaps I should rig up a way to run 120 VAC directly to the prongs on one LED bulb only, to see if it works. Thanks in advance. I can take photos if this is hard to visualize.
 
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Do you have a part number for the new bulbs? Or even just a link to the product page? Edit: I did a quick search, it seems some leds are direct wire but not necessarily all of them can be directly wired.
 
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Number_35

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JB, the part number is VPLT-15W2G10. I don't know who the manufacturer is - I thought Intertek, but that appears to be a standards [censored]'n rather than the manufacturer. I'll try to post some photos tomorrow.
 
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There are two types of replacement LED light bulbs/tubes. 1. One type allows you to use the ballast already in the fixture from the Fluorescent light. 2. One type requires you to remove the ballast. I chose to purchase the LED replacements that require I remove the ballast simply because a ballast isnt needed and an additional energy waste. Not only that, it was developed for Flourescent Lighting and I am now putting in LED tubes. You need to be aware of this when purchasing in order to select the right type.
 
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I just converted the kitchen lights at both our homes to LED and my wife's sewing and art room to LED. The bulbs I purchase at Home Depot and Walmart and the 8ft tubes were purchased on ebay. The one from HD say to wire them for direct outlet power and to remove the ballast. Also on the 8' bulbs from ebay. The Wally world ones only work with a ballast and then only some ballasts. I tried them in our kitchen light and they would run for maybe 45 min and shut off. Some ballasts don't work with them. Other house kitchen has a 4 X4 foot unit and they work there just fine. There needs to be some better info on these bulbs about their power requirements. The average Joe won't figure out why what he bought refuses to work.
 
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Originally Posted by vwmaniaman
I just converted the kitchen lights at both our homes to LED and my wife's sewing and art room to LED. The bulbs I purchase at Home Depot and Walmart and the 8ft tubes were purchased on ebay. The one from HD say to wire them for direct outlet power and to remove the ballast. Also on the 8' bulbs from ebay. The Wally world ones only work with a ballast and then only some ballasts. I tried them in our kitchen light and they would run for maybe 45 min and shut off. Some ballasts don't work with them. Other house kitchen has a 4 X4 foot unit and they work there just fine. There needs to be some better info on these bulbs about their power requirements. The average Joe won't figure out why what he bought refuses to work.
Yes, I agree, people think all they have to do is buy the equal in an LED and they dont know there are two types. For anyone comfortable, without question, the way to go is remove the ballast, its not needed or used for LED unless you buy a special LED build that will work with it. Key is to check labeling on the package and maybe part number on manufacturers website, in order to know what you bought.
 
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Originally Posted by alarmguy
There are two types of replacement LED light bulbs/tubes. 2. One type requires you to remove the ballast. I chose to purchase the LED replacements that require I remove the ballast simply because a ballast isnt needed and an additional energy waste. Not only that, it was developed for Flourescent Lighting and I am now putting in LED tubes.
I thought all of them required bypassing (or removing) the ballast and just hard-wiring them.
 
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There are two types of LED bulbs used once the ballast is removed. One is wired at one end of the bulb only, the other requires one wire on one side, one on the other.
 

Number_35

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Guys, it's all moot. I opened up the three LED bulbs, and the electronics are smoked. A capacitor on each circuit board has split open and barfed out its contents. I now have three expensive pieces of e-waste. GRRRR! If I'd known the electronic ballasts had to be removed from the lamp first, I would have done so. There were no separate instructions supplied. As you can see in the last photo, the instructions listed on the bulb's heat sink are a bit vague. I'll reinstall the fluorescent bulbs, and replace the lamp at some point, ensuring that it comes with LEDs.
 
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Originally Posted by hallstevenson
Originally Posted by alarmguy
There are two types of replacement LED light bulbs/tubes. 2. One type requires you to remove the ballast. I chose to purchase the LED replacements that require I remove the ballast simply because a ballast isnt needed and an additional energy waste. Not only that, it was developed for Flourescent Lighting and I am now putting in LED tubes.
I thought all of them required bypassing (or removing) the ballast and just hard-wiring them.
Nope. Some LEDs MUST have the ballast still installed and working, others require removing the ballast. And then there's a third type of LED: The "hybrid" tube, which can work with or without a ballast. I have these in my garage. One fixture still has the ballast installed, the other doesn't. Both fixtures have the same LED tubes. I'll be removing the other ballast soon, since it recently started making this annoying ringing sound when I turn it on.
 
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Originally Posted by Propflux01
There are two types of LED bulbs used once the ballast is removed. One is wired at one end of the bulb only, the other requires one wire on one side, one on the other.
That's another good point. T8 fluorescent tubes typically use shunted sockets, which you cannot use with single-end power LEDs. If you're retrofitting a T8 fixture, you need to either use double-end power tubes, or replace the sockets with non-shunted ones. T12 fluorescent tubes typically use non-shunted sockets, so you can easily convert to single or double end powered LEDs.
 
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Oh good luck to you on that one my past post I was thinking they were standard fluorescent tubes such as t5, t8 ect
 
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That's another good point. T8 fluorescent tubes typically use shunted sockets, which you cannot use with single-end power LEDs. If you're retrofitting a T8 fixture, you need to either use double-end power tubes, or replace the sockets with non-shunted ones. T12 fluorescent tubes typically use non-shunted sockets, so you can easily convert to single or double end powered LEDs.[/html]

My experience is that they don't use shunted sockets. If they did I would have had a hard time reusing the wiring for single-ended ballast bypass where I would have had a hard time pulling out the socket. I have this really difficult setup where I couldn't figure out how to remove the socket when I might have wired a new socket.

I've seen they typically use non-shunted sockets, but a two-lamp ballast includes two red and two blue wires to connect to one end, then two (common) yellow wires that are usually bridged to connect to four pins on the other end of the tubes.

3lamp-series-ballast-wiring-diagram.png


As for the OP, it looks like the setup wasn't meant for that. The fixture setup looks like it has ballast components right there. To wire it properly would mean wiring the line to two pins on the same side and neutral to the other two pins on each socket. Regardless - this doesn't give me the impression of being of the highest quality.
 
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