Fluorescent ballast repair - Page 1
Forum section: electronics / repair

author: Peabody
author_rank: Super Contributor
timestamp: May 06, 2019, 10:51:47 pm
content: I have a houseful of, actually nine, flourescent ballasts for T12 F40 pairs, dating back to 1972. They work fine during the winter, but in warm weather they don't turn on very fast, sometimes taking several minutes to come on, if at all. But they aren't actually dead because if things cool down they work fine again. Putting in new tubes doesn't change anything.I'm embarrassed to say that I don't know what's inside a fluorescent ballast that's almost 50 years old, but since an increasing number of my ballasts have exactly the same problem, I have to assume that there's a particular part or type of part that deteriorates over time and causes this effect. Actually, I'm a bit puzzled by the temperature profile I see, because I would have expected that it would be less likely to start when cold, but it's actually just the opposite.So having nothing better to do, I thought I might try to repair them. Replacement would cost about $25 each, and switching everything to no-ballast LED, which is what I would actually have to do, more than that. So if I can repair the ballasts, I'd like to do that. 120VAC here, if it matters.It's been demonstrated scientifically that if someone who doesn't know anything about classical music asks you to identify a classical piano piece he has heard, 72.97% of the time the correct answer is Beethoven's "Fur Elise". Similarly, if an electronic circuit's performance begins to deteriorate, but does not completely fail, I think the reason is usually "capacitors" with perhaps even higher odds than Beethoven. Is that the explanation here? I mean, other than gradually failing solder joints, it's hard to imagine what else it could be, particularly when multiple ballast examples show exactly the same symptom.Does anyone here have any experience looking inside ballasts? Are they repairable (within reason)? Is there anything else in there besides capacitors that's likely to explain what I'm seeing? I guess I'm kinda assuming I will be able to get inside these ballasts, and that they aren't potted.The other 27.03% of the time it's split between Mozart's Turkish March and Debussy's Clair de Lune, which might correspond to diodes and switching transistors. But nobody ever hears Brahms, and it's never a resistor.

author: rhodges
author_rank: Frequent Contributor
timestamp: May 06, 2019, 11:37:02 pm
content: What the heck, I will throw in my opinion until someone really knowledgeable chimes in. Your ballasts are probably just inductors and the problem may be the "starters". The starter is (was) a small cylinder with two electrical lugs. When you first apply power, the starter gives power to the tube filaments so that they can get the gas ionized. Then after a few blinks, the tube is ready to go and the starter shuts off. I think there may be a tiny heater wire and thermo switch in the starter.Hypothesis: If a starter is defective, maybe its thermo switch can work when the ambient temperature is low, but a higher temperature might make the starter "think" the tube is already going.

author: EOC_Jason
author_rank: Contributor
timestamp: May 07, 2019, 12:08:15 am
content: Those old magnetic ballasts probably aren't worth the effort. Every one I've seen has been potted in like tar or some other substance, so cleaning that out alone would be a major PITA and I don't know if it could be done without damaging anything...

author: edavid
author_rank: Super Contributor
timestamp: May 07, 2019, 02:48:44 am
content: Look again, Amazon has a 10 pack of T12 electronic ballasts for $90, or singles starting at $11 each. Well worth it to get rid of ballast buzz.

author: Gregg
author_rank: Super Contributor
timestamp: May 07, 2019, 03:32:44 am
content: I'm a big fan of Fulham Workhorse ballasts; they seem to be the best reliability and quality for the $.As previously stated, most old magnetic ballasts are potted in tar and not worth the effort to even try to repair and even if you succeed, you'll still have an inefficient buzz box ballast with line frequency strobe effects.

author: bob91343
author_rank: Super Contributor
timestamp: May 07, 2019, 03:36:39 am
content: I have gone through taking apart tar potted inductive components. Yes it's a pain and a very messy one at that. But that's what you go through to get inside.However, as someone mentioned, it's just an inductance and is unlikely to be the cause of the problem. The starter is more often the source of trouble.I have a box of starters I have had for decades. I presume they are still good. If I remember correctly there is some kind of gas filled tube in there that breaks down and allows the ballast to provide an inductive kick sufficient to strike the ionization. I never really understood fluorescent lamps.My workbench lamp has a manual starter. You hold the button down until the tubes glow and when you let up it lights properly.

author: Peabody
author_rank: Super Contributor
timestamp: May 07, 2019, 04:20:36 am
content: Thanks very much for the replies. Since posting I've done more research, and I now have a different picture of what my options are.First, you certainly can get replacement T-12 ballasts, and even entire fixtures, at a reasonable price, but it's not clear how much longer T-12 tubes will be available, or at what cost. What I read is that T-12s aren't being made or imported anymore. So that's a question going forward. KInda like what I face with my R-22 AC compressor.At the same time, the cost of LED replacements has come down a good bit since I last looked. And it appears that what makes sense is to switch over to direct-mains-powered LED tubes. While they make LED tubes that work with ballasts, I don't know why I would want to continue to be subject to ballast issues. What makes more sense to me is the ones that run directly off AC, with line and neutral at one end, and dummy pins at the other end. And it appears that my existing T-12 tombstones are even the right type for these LED tubes. So I would just remove the ballast and toss it, and rewire the tombstones directly to mains.I find this at the Home Despot:https://www.homedepot.com/p/Viribright-4-ft-40-Watt-Equivalent-Ballast-Bypass-Cool-White-4000K-Single-End-Power-T8-LED-Tube-Light-Bulb-12-Pack-750329-12/302327728And that's before my 10% veterans discount. It would do my entire kitchen. Then I might pick something warmer for the bathrooms.What do you think of this option? It seems like a fairly low-cost way to put all the obsolescence issues behind me, with really easy conversion, and maybe save a few bucks a month on power going forward.

author: james_s
author_rank: Super Contributor
timestamp: May 07, 2019, 05:02:43 am
content: Are these rapid start or are they old enough to be preheat start with the separate little can starters?In the US, fluorescent ballasts for lamps larger than 24" are autotransformers. The older preheat start type are typically a lead-lag configuration that puts a capacitor in series with one of the lamps so they run out of phase to reduce strobing. Rapid start ballasts run the lamps in series with an isolated aux winding that provides cathode heat in the middle ends of the two lamp string.The most common cause of fluorescent lamps not starting when using rapid start ballasts is that the reflector is not properly grounded. This is particularly problematic during times of high humidity.I use T8 tubes and electronic ballasts in most of the fluorescent lights I have, but I do like the old preheat start T12 lights. The ballasts are less efficient but they tend to run the tubes a bit hotter so they're nice and bright.

author: Peabody
author_rank: Super Contributor
timestamp: May 07, 2019, 02:15:37 pm
content: Quote from: james_s on May 07, 2019, 05:02:43 amMine don't have the separate can starters, so I assume they are rapid start. Attached is a pic one one of them.QuoteI would never have guessed that one. And I assume the ballast case has to be grounded to the fixture too, presumably through the "U" at one end where the screw goes. I thought the ground was just for safety, but I see now that the ballast itself says the tubes need to be near ground. Well, easy enough to make sure the ground is there. Maybe that will be the solution. Thanks very much.

author: PaulAm
author_rank: Frequent Contributor
timestamp: May 07, 2019, 02:42:53 pm
content: I ran across a deal for direct wire LED tubes a while ago and put them in my workshop. Wish I had bought more, they're great. I think it was around $6-7/tube.I bought some LED tubes on closeout at one of the big box stores that worked with a ballast. That was a waste - they only work with some ballasts and are not compatible with the ones I have. Stick with the direct wire types. Those tubes are going in the donate pile.I've also started replacing the HIDs in my shop with LEDs. Those can get pricey.

author: edavid
author_rank: Super Contributor
timestamp: May 07, 2019, 03:07:51 pm
content: Quote from: PaulAm on May 07, 2019, 02:42:53 pmWell, I had the opposite experience. I first tried some direct wire ("bypass") tube replacements, but they had unacceptably slow turnon. I'm glad I figured that out before replacing all the tombstones in the fixtures (a common requirement for the bypass products).Then I bought some cheap Philips ballasts and ballast compatible tube replacements, and the results were excellent.Both types of tube replacements were "Utilitech" brand from Lowe's, and cost about $4 each, but I'm sure they have different models by now.

author: james_s
author_rank: Super Contributor
timestamp: May 07, 2019, 03:29:44 pm
content: Yes that says RS, so rapid start. It's an autotransformer ballast with the lamps in series. The yellow wires come from an isolated winding that provides cathode heat, the pairs of red and blue wires come from the ends of the secondary and have a tap to get a few volts between each pair to heat the cathodes (filaments) in that end of the tubes. It's a high power factor ballast so there will also be a PFC capacitor in there and usually there's a small capacitor across one of the lamps to aid starting. The whole thing is potted in tar to make it quiet so unless you want to go through the very messy and stinky process of melting out the tar there is not much you can do.RS ballasts rely on having a grounded plane near the lamps for reliable starting since they lack the inductive kick produced by a conventional ballast and starter arrangement. Capacitive coupling helps to ionize a small amount of the argon in the tube at which point the lamp will ignite. You may find that passing your hand over a stubborn tube will cause it to light up, that's a pretty good indication that you have a grounding problem.

author: oolloo
author_rank: Contributor
timestamp: May 09, 2019, 12:23:39 pm
content: I'm not sure why you would want to use fluorescent lamps. 4 years ago I replaced all my lamps with ballast compatible led T12's , fixtures (they're 40 years old ) home depot was not sure, they told me the led tubes aren't compatible , because they're not as thick. That was in 2015Tried to sell me all in one led soldered fixtures $200 each (Canada same $ to usd as Au. )At Costco Canada ISpotted a 2 tube led pair, ballast compatible lamps for $17, it consumes almost half the electricuty, brighter and instant on. Your thinking "but my ballast is the issue"I know, there are dozens of videos on YouTube regarding eliminating the ballast to save exactly half the electricity . LED doesn't require it.My tubes have paid for themselves many times over , $9 A piece vs $2-4. Up front I bet they're cheaper now, even dollar stores sell led light bulbs now.

author: 6PTsocket
author_rank: Regular Contributor
timestamp: May 09, 2019, 12:37:49 pm
content: Quote from: bob91343 on May 07, 2019, 03:36:39 amI have a magnifier circline lamp clamped to the bench. When the 3 position rocker switch (off, on, push to start) failed and it was hard to get a replacement I installed a starter and a regular on-off switch.Works great.Sent from my SM-G900V using Tapatalk

author: bob91343
author_rank: Super Contributor
timestamp: May 09, 2019, 02:48:19 pm
content: Very nice! Can you give details as to just how you installed a starter? I find the push-and-hold method a bit tiresome and wouldn't mind having it start automatically.

author: soldar
author_rank: Super Contributor
timestamp: May 09, 2019, 02:52:55 pm
content: Quote from: james_s on May 07, 2019, 05:02:43 amI can confirm this. Many people do not know this.I am switching over to LEDs as I change lights here and there but I still have a bunch of old ones with inductor ballasts and they work well.The old system of ballast and starter worked pretty reliably and if it wasn't working the ballast was the least suspect and the problem was much more likely to be with the tube or with the starter. And the starter could be replaced with a momentary switch for testing.Cheap inductor ballasts got hot and wasted energy but in general they were OK. Another problem was reactive energy and you would need capacitors to counteract this.

author: soldar
author_rank: Super Contributor
timestamp: May 09, 2019, 02:55:15 pm
content: Quote from: bob91343 on May 09, 2019, 02:48:19 pmThe starter is just a switch which is normally open when the tube is on but will close momentarily when it is off. It is very ingenious. Have a look herehttps://home.howstuffworks.com/question337.htm

author: james_s
author_rank: Super Contributor
timestamp: May 09, 2019, 02:59:52 pm
content: Quote from: bob91343 on May 09, 2019, 02:48:19 pmYou wire it just like any other preheat fluorescent lamp. The starter connects to one pin on each end of the tube. The ballast is a choke coil in series with one of the AC line wires feeding the remaining pins. The ballast is a series impedance just like the resistor used to ballast an LED. The starter is nothing more than an automatic switch that shorts across the tube allowing the cathodes to draw power and heat up, then the starter opens and you get a spike that strikes the arc.You should be able to just follow the wires from the switch, disconnect the two to the start section and connect them to the starter.

author: james_s
author_rank: Super Contributor
timestamp: May 09, 2019, 03:09:53 pm
content: Their description of how a starter actually works is wrong. The starter is a normally open bimetal switch in a glass tube containing argon or neon. When power is applied a glow discharge strikes inside the starter and that heats the binetal strip causing it to close. This shunts the current away from the discharge in the starter so it goes out while the cathodes are heating at the same time. The starter now cools off and the contacts pop open, creating the spike that strikes the tube. The running voltage of the tube is lower than the striking voltage of the open starter so nothing more happens.That is until the lamp is worn out and the cathode emission drops causing the lamp voltage to rise. This is why worn out tubes often cycle and flash on preheat systems. This is also why the starter has to be matched to the tube type, there are two common types, one for shorter tubes on choke ballasts and one for longer tubes on autotransformer ballasts (in 120V land.)

author: schmitt trigger
author_rank: Super Contributor
timestamp: May 09, 2019, 03:47:56 pm
content: I used to work for a ballast manufacturer.An electronic ballast will provide 10 to 20% efficiency gains. Also, because they operate at high frequency, the 50/60 Hz flicker is completely gone. And you have no ballast buzz.As others have stated, the ballasts are filled with sand-filled tar. Excellent environmental protection and noise damping, but extremely difficult to remove. And you will (mostly) only find an inductor. Some two-tube ballast do have some paper capacitors, to create an arc-current phase shift, in an effort to reduce powerline flicker. These capacitors, like all capacitors which carry significant amounts of current, will degrade over time.What I find puzzling is your report that at colder temperatures the ballasts work better. Usually is the other way around.

author: james_s
author_rank: Super Contributor
timestamp: May 09, 2019, 04:43:00 pm
content: Quote from: schmitt trigger on May 09, 2019, 03:47:56 pmColder temperatures typically mean lower humidity, this is particularly true in some parts of the world where summers are extremely humid. High humidity bleeds off charge and makes it harder for the lamps to ignite. Due to the multiple factors involved, warmer days may exhibit the problem more than colder days, especially if the lamps are indoors where they may never get cold enough to have cold weather starting troubles but they do see the high summer humidity.

author: steve1515
author_rank: Regular Contributor
timestamp: May 09, 2019, 06:56:46 pm
content: I've been thinking about upgrades to my old T12 and T8 lights also. The choice that I've ended up with is get new electronic ballasts and go all T8 lamps or go with direct wire LED tubes. The problem I always noticed was that the florescent lumen value was always more then the equivalent LED.For example...The regular T8 linked here is listed as 2600 lumens.https://www.homedepot.com/p/Philips-32-Watt-4-ft-Alto-Linear-T8-Fluorescent-Light-Bulb-Cool-White-4100K-2-Pack-479667/303811442The LED replacement linked here is listed as only 2100 lumens.https://www.homedepot.com/p/Philips-4-ft-32W-Equivalent-Cool-White-Linear-T8-LED-Light-Bulb-472878/303810126It seems that every time I start looking at LED replacements, I find that equivalent LED lamps don't have the same light output. Or at least that's what it looks like to me when reading the specs. Why don't they make LEDs that have the same amount of light output? Or, is this not how the lumens value works?

author: soldar
author_rank: Super Contributor
timestamp: May 09, 2019, 07:54:36 pm
content: Quote from: james_s on May 09, 2019, 03:09:53 pmYes, I noticed that too. The first explanation is wrong but there is another one below which is correct.

author: schmitt trigger
author_rank: Super Contributor
timestamp: May 09, 2019, 08:30:00 pm
content: The important parameter to compare is the lumens per watt.And the color rendering index -CRI.The original LED lamps had poor CRI. My wife made me change the lights back to CFLs in the vanity mirror lights, as the makeup would look odd.Nowadays, newer and more expensive units actually have a very good CRI.

author: Peabody
author_rank: Super Contributor
timestamp: May 09, 2019, 10:26:40 pm
content: @schmitt trigger:QuoteYes, that was my reaction. But it's absolutely predictable, for multiple ballasts - now up to four that behave exactly that way. They misbehaved late last summer, worked perfectly all winter, and are now acting up again. I have a drop ceiling, so the light fixtures are in the relatively unheated/uncooled area near the attic, and thus closer to the outside temperature. I don't think it has anything to do with humidity. We've had a week of rain, but with a bit colder temps, and all the lights work fine. But when it warms up, they'll go flaky again and I'll be able to test the grounding fix.@steve1515:The explanation I've seen is that in the case of LED tubes, all of the light is directed down into the room, whereas a significant portion of the light from a fluorescent tube goes up into the fixture and has to bounce back down, with considerable loss. So the net effect is that the LEDs actually produce as much room light even though they are rated at lower light output. The videos I've watched on Youtube seem to confirm this.The big issue, as schmitt trigger says, is the CRI, which I had not fully considered. Apparently LED tubes with low CRIs can make things look really goofy. But I don't know what the CRI of a cool-white fluorescent tube is.

author: edavid
author_rank: Super Contributor
timestamp: May 10, 2019, 01:45:41 am
content: Quote from: steve1515 on May 09, 2019, 06:56:46 pmI think the rated lumen value for fluorescent tubes is very optimistic, or only applies for the first 5 minutes of use. I replaced a bunch of Philips "2800 lumen" tubes with "2000 lumen" LEDs, and the LEDs look much brighter. I think true 2800 lumen LEDs would be too bright.

author: james_s
author_rank: Super Contributor
timestamp: May 10, 2019, 04:37:51 am
content: The lumen value is normally the rating after 100 hours where the output has stabilized after the initial drop and begins a long slow decline over the rated life. At 70% output the lamp is considered end of life. It also assumes full rated power but many ballasts under-run the lamps somewhat. The other issue is that fluorescent tubes emit their light evenly around 360 degrees so a considerable amount is lost in the fixture. LED tubes typically are somewhat directional resulting in somewhat more of the light getting where you want it and even higher apparent brightness of the source.All types of lamps are measured in an integrating sphere which measures the total output of the lamp. It doesn't differentiate emission patten and obviously can't account for fixture design, both of which have a large effect on the real world performance.

author: james_s
author_rank: Super Contributor
timestamp: May 10, 2019, 04:51:57 am
content: Quote from: Peabody on May 09, 2019, 10:26:40 pmThe traditional Cool White halophosphate phosphor has a CRI of around 60 so quite low. The fancier lamps with trichromatic rare earth phosphors are available with a CRI of 70+, 80+ and there are some high end lamps that add a true red phosphor to get the CRI to 90+ for a penalty of about 40% lower output for the same wattage. You can identify these from the type number, for example F32T8/850 is a 32W T8 (1" diameter) lamp with a CRI of at least 80 and a color temperature of 5000K. F32T8/735 is a 32W T8 with a CRI of at least 70 and a color temperature of 3500K.The thing about CRI is it's a bit of a numbers game, so it's a useful metric but that doesn't mean that two different types of lamp with the same CRI will render colors exactly the same.

author: soldar
author_rank: Super Contributor
timestamp: May 10, 2019, 01:50:06 pm
content: A classic and very good page on this topic isQuotewhich used to be online in HTML but now I can only find in this pdf:https://www.lightingassociates.org/i/u/2127806/f/tech_sheets/Fluorescent_Lamps__Ballasts__and_Fixtures.pdf

author: Peabody
author_rank: Super Contributor
timestamp: May 10, 2019, 03:48:13 pm
content: I looked at the box of basic Philips cool white F40T12's I get from Home Depot, and they show a CRI of 89. I guess that's ok. I've never really noticed any color issues with them. So I would think an LED tube with a CRI of 90 or higher should look ok. But when you get down to it, none of this stuff is exactly broad spectrum like you get from natural light or even incandescent.

author: james_s
author_rank: Super Contributor
timestamp: May 10, 2019, 04:36:42 pm
content: That's surprising, I wonder if they're using rare earth phosphors in all their lamps now and just calling that color temperature cool white?Incandescent has a CRI of 100 as does natural daylight. Most 90+ sources are pretty close but again it's a bit of a numbers game, it doesn't tell you everything.

author: schmitt trigger
author_rank: Super Contributor
timestamp: May 11, 2019, 02:27:26 pm
content: The very best lamps, CRI-wise, are halogens.That is the reason they are almost exclusively used in museums to illuminate paintings or other art objects.Their disadvantage if you can call it that way, is that they are incandescents.Other than that, it’s light is the closest to natural daylight.

author: 6PTsocket
author_rank: Regular Contributor
timestamp: May 11, 2019, 03:06:11 pm
content: Quote from: bob91343 on May 09, 2019, 02:48:19 pmThe manual start switch is a 2 pole switch (see diagram). Section A is the power switch that is off in the "off"position and on in the "on" and "start" positions. Section B is only closed in the "start" position, which returns to the "on" position when you let go. Just replace section A with a single pole on-off switch and install the starter where section B is in the diagram. I was able to find a starter socket. Use a starter that is rated for the wattage of the bulb you are using. Mine was 22 Watts. Starters usually cover a range, like 20 to 25 Watts. The trick is finding a place for everything. I had to do a little "body work" to reduce the size of the switch mounting hole, as the 3 position switch was larger. The starter is buried inside.Sent from my SM-G900V using Tapatalk

author: james_s
author_rank: Super Contributor
timestamp: May 11, 2019, 05:08:28 pm
content: Quote from: schmitt trigger on May 11, 2019, 02:27:26 pmThe CRI of halogens is identical to the CRI of ordinary incandescent lamps and sunlight, it's 100, as high as CRI goes. Halogens typically have a slightly higher color temperature though, not nearly as high as daylight but closer. They also tend to be a bit more energy efficient and longer lived. As I mentioned earlier, CRI only tells part of the story.

author: james_s
author_rank: Super Contributor
timestamp: May 11, 2019, 05:14:05 pm
content: Quote from: 6PTsocket on May 11, 2019, 03:06:11 pmYou should be able to leave the original switch in place in many cases and just use only the on/off portion. Some lamps though use pushbuttons where the "On" button is the starter and the "Off" button just momentarily interrupts the power when pressed, pretty clever.If you need more space, the glowbottle and suppression capacitor are easily removed from the starter can and are much more compact. A piece of heatshrink can be used to protect them.

author: bob91343
author_rank: Super Contributor
timestamp: May 11, 2019, 05:33:06 pm
content: Thanks! I'll give it a try shortly and let you know.

author: Peabody
author_rank: Super Contributor
timestamp: June 27, 2019, 11:45:54 pm
content: Faithful viewers will remember that in our previous episode I was trying to find a solution for the problem I was having with about half of my nine T12 fluorescent fixtures which date back to 1972. When I flip the power switch, they don't turn on. Some turn on a minute or more later, others not at all. This only happens in warm weather - they acted up beginning late last summer, worked perfectly all winter, and are now acting up again. Of course that seems ass backwards, but that's the way it is. New bulbs don't help.I found that touching either bulb in the fixture would cause both to turn on immediately, and sometimes just getting my hand very close would do it. Based on expert advice here, I concluded that this must be a grounding issue. The fixture housing has to be grounded for T12s to start up. So I've gone through all of the fixtures, made sure that the ground wire was properly connected to each fixture housing, and that each ballast housing was also connected to the fixture housing. But none of that did any good.Since this affects fixtures in both the kitchen and the bathrooms, which started misbehaving about the same time, I began to wonder if perhaps things are not grounded properly at the electric service entrance. I checked outside, and the ground stake is still there, and the cable is still connected from the stake to the meter. Of course I can't get into the meter housing, and wonder if there is a way to test whether I have a good house ground connection. I could take off the front panel of the breaker box, but don't know what that would show me. I doubt the actual ground connection even comes into that box, but suspect it is connected to Neutral at the meter.The only testing option I see at this point would be to switch two of the ballasts - one that rarely starts properly, and one that, so far, always does, and see if the problem goes with the ballast. This would test the theory that it's the ballasts going bad. But I'm having trouble with the idea that a large percentage of the ballasts would start to fail at the same time after working fine for 46 years. That would be really fine-tuned planned obsolescence. And of course if the problem doesn't go with the ballast, I'm back to grounding.But then stepping back, I think it may be time to accept defeat, and switch all the fixtures over to LED tubes. I know they make LEDs that work with existing ballasts, but I really don't want to be depending on ballasts anymore - even if they aren't the problem now, they aren't going to last forever. And if they are the problem, or become a problem, I certainly don't want to have to replace them. So I'm looking at single-ended direct-wire (to AC) LED tubes. I'll have to confirm it, but I think my T12 tombstones are even right (non-shunted) for such tubes, which means the most burdensom part of doing the replacement might actually be having to take the 9 ballasts and 18 bulbs to recycle.I don't believe T12's are being made anymore, and they continue to become more and more expensive. I suspect the same thing will happen to ballasts. I have enough of that kind of problem with my R22 AC system, so maybe this is just the time to move the lighting to the modern world. This appears to be the best deal for me:https://www.amazon.com/gp/product/B01N524Y6T/My main reservation is the CRI, which is either 82, 84 or 85, depending on what Hyperikon spec sheet you look at. My current fluorescents are CRI - 89, 4100K, so I hope the LEDs will look about the same. My secondary reservation concerns the odds of receiving 24 unbroken glass tubes through Amazon shipping.Have I missed a trouble-shooting step? If not, do the LED's make sense?

author: wraper
author_rank: Unknown
timestamp: June 27, 2019, 11:59:29 pm
content: Quote from: edavid on May 10, 2019, 01:45:41 amFluorescent bulb brightness decreases with time. LEDs degrade too but it highly depends on particular LED type and how hard they are driven. As of LED lamp with lower lumen rating being brighter, they usually are way more directional, even those which look similar to incandescent bulbs. Fluorescent bulbs un the other hand shine in all directions including upwards, thus more light is lost needlessly.

author: james_s
author_rank: Super Contributor
timestamp: June 28, 2019, 03:02:27 am
content: I think I would check the grounding regardless of what you do with the lights. I would measure resistance between neutral and ground and then maybe try connecting an incandescent lamp between hot and the grounded reflector of one of those fluorescent lights and see if it lights.

author: NiHaoMike
author_rank: Super Contributor
timestamp: June 28, 2019, 03:30:26 am
content: Quote from: soldar on May 10, 2019, 01:50:06 pmCurrent copy:http://www.repairfaq.org/sam/flamp.htm

author: Peabody
author_rank: Super Contributor
timestamp: July 10, 2019, 11:32:05 pm
content: This is what I hope is my final report on this. I ordered Hyperikon LED tubes from Amazon, which were direct-connect, ballast-bypass, single-ended frosted glass 4000k tubes. I ordered a 24-pack, and only 4 were broken, which was good because I actually needed 18. The cost was about $136 plus tax. Counting the wire stripping tool and the push-in connectors, I've got about $165 into this altogether. But I was able to return a $28 10-pack of T12s that I had recently purchased from Home Depot. So cost-wise it turned out ok, assuming the LED tubes last a while.I was fortunate in that I was upgrading from T12 since all my tombstones were non-shunted, and the wiring to the second tombstone of each pair was already in place. So I just connected the Line lead to one existing yellow wire, and the Neutral lead to the other. I removed all nine ballasts, and found two that were running very hot - too hot to touch. Five of the nine ballasts contained PCBs, including the two hot ones. I've confirmed that my city's hazardous disposal operation will take both the old tubes and the ballasts. So whatever the cause of my starting problems (probably those two hot ballasts), I think it was time to do this, and I'm glad to have all the fluorescent rubbish out of my house. And of course the LEDs turn on instantly.It was physically difficult because I was working up over my head, and dealing with the drop ceiling panels and the fixtures and the existing wiring. The wire stripper saved a lot of time, but the big hit of the operation was the push-in connectors - they are wonderful. The whole project replacing 18 tubes took about 3.5 hours including a few breaks.The packaging of the LEDs is wholly insufficient for glass tubes. To replace the four broken tubes, Amazon has to send me another 24-pack, and I'm supposed to take four tubes out of that and return the rest. They furnished the shipping label. But I just know that some of the replacement 24-pack will also be broken, and even more broken on the way back to them. So it's gonna be a real bureaucratic mess before all is done. Non-glass tubes are available, but they cost more.Lighting wise, the LED tubes look identical to the bulbs I took out. The brightness is the same, and as far as I can tell the CRI is ok. These are 82, whereas the fluorescent cool white bulbs claimed to be 89. But I don't see any difference. Colored things don't look strange, at least not that I've noticed so far.I guess if I had had modern electronic ballasts I would have considered getting the LED tubes that work with those ballasts. That's particularly if I had had T8 bulbs and shunted tombstones. But my ballasts dated back to 1972, and I'm convinced that taking those out and using direct-connect tubes was the way to go, and I didn't have to replace any tombstones, which would have been a real pain with the fixtures I have.So the bottom line is I'm glad I did this upgrade, and believe the cost was reasonable. In picking the replacement tubes, you just have to be careful about what you're upgrading from (shunted or non-shunted tombstones, magnetic or electronic ballasts) when picking which LED tubes to buy.