LED ballast failure. Something to reflect upon into specs requirement language

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Electric-Light

Electric-Light

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Fluorescent lamps are rated at 50% survival. That is, if you have 100 lamps that are rated at 46,000 hrs at 12hrs per start, you can expect about half of them to remain lit. Lamps have a longer practical lifespan now than the past, because they're parallel wired. So, one failure, one outage. Not one fail, a string of two out. The failure rate is such that a few starts failing, then you'll suddenly have large quantities failing. Practically speaking, you can get about 70-80% of rated life. Usually you have many of them close together and they provide redundancy like dually tires.

Street lamps are usually rated differently. They're rated to 70% survival. This takes into consideration that each and every lamp has a significance in lighting and one failure can make immediate replacement necessary to continue providing lighting function.

LEDs behave very similarly to fluorescent lamps except for not need a ignition strike. They both behave different from resistors and both require a ballast to maintain proper operating conditions. The LED element is just a part of the drive train and misleading claims such as LEDs gradually darken and not fail do not apply to the lamp system as a whole.

My recent observation of the failure mode of consumer LED lamp GE Bright Stik LED 10LS/DL (CHINA K141) strongly suggests purchasing specifications should be amended to disallow certain failure types and acceptance of remedy cost for such failures. The LED elements did not fail, but the LED ballast failed in a way that caused it to malfunction by strobing in a very rapid succession like a disco light which could cause disorientation. This is the kind if failure that may require aerial boom brought in the next day to address one bulb. An emergency repair clause should be tacked onto LED installs so that LED vendors are held accountable for this type of incidents.
 
Electric-Light said:
Fluorescent lamps are rated at 50% survival. That is, if you have 100 lamps that are rated at 46,000 hrs at 12hrs per start, you can expect about half of them to remain lit. Lamps have a longer practical lifespan now than the past, because they're parallel wired. So, one failure, one outage. Not one fail, a string of two out. The failure rate is such that a few starts failing, then you'll suddenly have large quantities failing. Practically speaking, you can get about 70-80% of rated life. Usually you have many of them close together and they provide redundancy like dually tires.

Street lamps are usually rated differently. They're rated to 70% survival. This takes into consideration that each and every lamp has a significance in lighting and one failure can make immediate replacement necessary to continue providing lighting function.

LEDs behave very similarly to fluorescent lamps except for not need a ignition strike. They both behave different from resistors and both require a ballast to maintain proper operating conditions. The LED element is just a part of the drive train and misleading claims such as LEDs gradually darken and not fail do not apply to the lamp system as a whole.

My recent observation of the failure mode of consumer LED lamp GE Bright Stik LED 10LS/DL (CHINA K141) strongly suggests purchasing specifications should be amended to disallow certain failure types and acceptance of remedy cost for such failures. The LED elements did not fail, but the LED ballast failed in a way that caused it to malfunction by strobing in a very rapid succession like a disco light which could cause disorientation. This is the kind if failure that may require aerial boom brought in the next day to address one bulb. An emergency repair clause should be tacked onto LED installs so that LED vendors are held accountable for this type of incidents.
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My office lighting tells me that fluorescent ballasts can fail in very much the same way. What you are describing is electronics failing, not that actual light source. Therefore anything with electronics this can happen to, fluorescent electronic ballasts OR LED electronic drivers. Electronics have something called a 'bathtub curve' for failures. Defects quickly fail in the initial life of the product and as time goes on the failure rate goes down, until a point in the products life where failure rate starts to rise again with age of product.

Street lights, depending on light source type, have different failure modes. Traditionally its been either lumen depreciation or cycling.

You also say that fluorescent lights are parallel wired. This is not always true, and is more likely mostly false. When i specify fluorescent systems I always have to make a big stink about getting a parallel connected programmed start ballast. By default supplies like to throw series connected instant start ballasts at me because they are cheaper. I'd imagine the vast majority of people, either through ignorance or having price as a first priority, accept these cheaper versions.

To answer your concern, I typically spec and require a 5 year warranty AND require quality manufacturers. This tends to get rid of most issues. The lightstiks you mention, though a good quality brand, are on the low end of consumer grade. Their life expectancy is only 15k hours or something like that.
 
The electronic ballasts of fluorescent lamps can fail spectacularly. I had an advance optanium ballast which popped it's capacitors and then arced thru the case and shorted to the ground. Magnetic ballasts can fail too and splooge capacitor oil out, but this's typically due to energy saving lamps being used. Common example is 34w tubes being run on 40w ballasts. Even 34w rated ballasts will stress, due to the higher arc voltage the 34 watt tube requires. This causes coils to short or caps to pop, or both. This is a no brainer here, stick with good ol boys and make sure you don't screw it up lol. Also stuck starters on old preheat systems causing coil and cap stress, tho most old preheat fixtures I've seen have been desecrated with t8 or (shudders) led retrofits.
 
majorminotaur said:
To answer your concern, I typically spec and require a 5 year warranty AND require quality manufacturers. This tends to get rid of most issues. The lightstiks you mention, though a good quality brand, are on the low end of consumer grade. Their life expectancy is only 15k hours or something like that.
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Are you familiar with the way DSLR cameras use its xenon strobe to help auto focus? Then you know the flashing pattern. The flashing from this failing LED ballast is very much like that. I've seen induction street lights failing in blinking mode, but usually they flash in aircraft beacon like pace. Not seizure strobe. They're public works grade. If they thought it through, it wouldn't be happening. Anyways, specification requirement barring failure in this manner should take care of it. The warranty language typical of lighting system usually don't recognize the labor and service charge made necessary to address nuisance, safety or regulatory compliance concerns(extreme flashing, acoustic or RFI emissions) caused by symptomatic failures. You can often postpone failed ballast change outs until scheduled relamp or maintenance to defray the cost of truck charge and scissor lift.

Coil and core sodium vapor lamps for example are very predictable and their failure behaviors are well understood as they're tried and true. Pages and pages of fine prints that assigns liability to LED vendor/selling contractor is needed to protect losses that can threaten to undo all savings due to unknowns arising from using experimental products.
 
majorminotaur said:
My office lighting tells me that fluorescent ballasts can fail in very much the same way. What you are describing is electronics failing, not that actual light source. Therefore anything with electronics this can happen to, fluorescent electronic ballasts OR LED electronic drivers.
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Yep, but the flashing pattern caused by this LED ballast failure is unreal. The interval, duration, the pattern are extremely annoying like nothing else. Very rapid series of full intensity millisecond flashes. Spend 15 seconds in this light and you see hot flashes for the next few minutes. This is something that should be addressed in design, but also put into the spec requirements so the facility owner can address it right away but legally charge the LED vendor for associated cost. You don't need to tap into the "what if" language if it doesn't happen and there's nothing to worry about if the vendors pushing LEDs are confident enough about what they're pitching.

Electronics have something called a 'bathtub curve' for failures. Defects quickly fail in the initial life of the product and as time goes on the failure rate goes down, until a point in the products life where failure rate starts to rise again with age of product.
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You see LEDs often touted as not having electronic ballast issues that affects CFLs, induction and fluorescent. One of the reason the LED industry tries to create an illusion that driver and ballast are different beyond semantics when they're really not. Many LED marketing materials criticize fluorescent ballast losses while ignoring LED ballast losses by calling it a "driver". Actually I personally believe LED ballasts are becoming more similar to fluorescent ballasts as LED strings operate at higher and higher voltage.

You also say that fluorescent lights are parallel wired. This is not always true, and is more likely mostly false. When i specify fluorescent systems I always have to make a big stink about getting a parallel connected programmed start ballast. By default supplies like to throw series connected instant start ballasts at me because they are cheaper. I'd imagine the vast majority of people, either through ignorance or having price as a first priority, accept these cheaper versions.
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Majority of fluorescent lamps in service today are parallel wired and the lion's share is 48" T8 driven on instant start. Series wired instant start lamps are not used in general lighting. The starting voltage requirement would be far excessive. Please provide ballast make and model for series wired instant start if you actually know of ones. The parallel wired instant start configuration can achieve limited dimming with about 1:2 dimming ratio which is useful for load shedding. In North America, instant start refers to starting a standard fluorescent lamp without preheating the cathode filaments.

Programmed, rapid, programmed, etc provides power to filaments for heating. This design commonly used series wiring. You can not tell if they're internally series or parallel visually for two lamp systems as the red, blue and yellow wire up the same. There are some 3 or 4 lamp ballasts that operate all of them in series like a sign ballast and they get complicated.

Parallel wired programmed start is a fairly recent thing. Yes, insist on them. Some 4 lamp T5HO ballasts are internally built as dual ballast where there are two separate ballasts meaning that each luminaire will have added redundancy. Lamp failure will only take out one lamp. A ballast failure will only take out two. It's an important consideration for high-bay fixtures where an entire outage of a single fixture can create a troubling dark spot.

To answer your concern, I typically spec and require a 5 year warranty AND require quality manufacturers. This tends to get rid of most issues. The lightstiks you mention, though a good quality brand, are on the low end of consumer grade. Their life expectancy is only 15k hours or something like that.
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Now, if one of them fail in extreme strobe mode, $20 ballast is the least of your concern. Proper conditions need to be set to require no flashing or that flashing cease within (say one day) and that LED vendor will send someone to fix within (say... 48 hrs) and that you can bill them for the spot repair if they can not satisfy that, which will be very expensive. The not fly-by-the-night LED vendors will be concerned about what this could end up costing them unless they're extremely confident about what they're pitching.
 
Fluorescent and HID lamp technologies are being sent to scrap yards and landfills by the truckload every day and that's one of the best things happening in our industry. :cool:
 
Maybe for electricians, but the consumers are getting screwed over. You can lamp an hid fixture with a good quality bulb, and depending on how many starts the bulb gets, not touch it again for another three years. LEDs however, the contrary. At a school there're these dimming led troffers. They're ok, but get a bit flashy at about 40 percent dimming. Then, a storm came and the power got cut. No bigge. Then, when it came back on an hour later and about 15 percent of them either died or were strobing like an Xmas light. The electronic 32 watt ballasts elsewhere still chugged along (surprisingly). Then, the magnetic ballasted HO turret in the engineering lab survived as well, as well as tandem 40 watt up lighting of the coffered ceiling. LEDs are the most efficient-they're off the most of the time!
 
You guys. :lol: Face reality - HID and fluorescent are going away and there is nothing that can be done to stop that. Up until very recently, I was highly skeptical of LED's and was highly reluctant to specify or install them. Now, I realize just how much better they are in every way: light quality, instant on, operation in cold weather, energy efficiency and complete reduction and elimination of maintenance.
 
peter d said:
You guys. :lol: Face reality - HID and fluorescent are going away and there is nothing that can be done to stop that. Up until very recently, I was highly skeptical of LED's and was highly reluctant to specify or install them. Now, I realize just how much better they are in every way: light quality, instant on, operation in cold weather, energy efficiency and complete reduction and elimination of maintenance.
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B-to-the-S. An example of superior fluorescent is given here. a friend got a few 2x4 preheat fixtures from a 1947 factory building, and the ballasts were dated as the same year. The factory ran its lights 24/6, for sixty years until shutting down in '07 sometime. They clocked in about 500k hours. Sadly they failed. BUT-before getting crap like "the old junk gone belly up, time for LEDs!",-keep in mind the lights remained from closure to a few months ago, drawing in moisture which otherwise would've been repelled by the running heat of an ideal function. The most recent lamps were I think c 1980s and they were good old boys, and the fixtures had the original starters. Now, LEDs however, have terrible light quality (the 5000k tubes I've seen spring up make everything feel like you're in the arctic circle. I'll give the cold weather tolerance to ya, since they need the coolness, otherwise they'd burn up!
 
Peter D, That's a bunch of bologna! LED's are just a fad, a trend!

Peter D, That's a bunch of bologna! LED's are just a fad, a trend!

peter d said:
You guys. :lol: Face reality - HID and fluorescent are going away and there is nothing that can be done to stop that. Up until very recently, I was highly skeptical of LED's and was highly reluctant to specify or install them. Now, I realize just how much better they are in every way: light quality, instant on, operation in cold weather, energy efficiency and complete reduction and elimination of maintenance.
Click to expand...


LED's ate just the latest, greatest fad, and have so many shortcomings it is unreal. Also, the term "LED" is a misnomer for GLS LED's. The PROPER name, though the manufacturers won't say it, is "Solid-state fluorescent" lamps. That's LED's are--FLUORESCENT light sources. Sure, there are the R-G-B LED's that mix the 3 primary colors to get various color temperatures of "white", but, LOL :lol: they do it at efficiencies usually as low or even lower than incandescent! SO, to get a decent efficiency (LED "lamps" or "tubes" will NEVER match the efficiency of fluorescent of HID sources, because of the law that 'many small lamps of ANY type are FAR less efficient than ONE larger lamp of any type---like 6 25 watt incandescent bulbs cannot come CLOSE to the efficiency and light output of ONE 150 watt incandescent bulb though they still draw 150 watts) and this is the killer of reaching true high efficiency in LED lamps! You can buy an 18-watt 4 foot LED "tube" to supposedly replace a 32-watt T-8 or 40-watt T-12 lamp. Sure, it will replace it, but it gives HALF the light output even if it LOOKS as bright. About 1800 lumens for the LED tube versus 3200-3600 lumens for the flourescent lamps. If the LED tube were 32 watts it would almost match the fluorescent lamp. SO---in an installation using 2-lamp open strips, installing LED retrofit lamps or complete fixtures would HALVE the light level. I could install 2 lamp 2 foot 17 watt lamps, spaced with a section of conduit 2 feet long between each fixture to equal the row length the 4 foot continuous-row fixtures made, and get JUST AS MUCH LIGHT as the LED junk. And the quality of light from the fluorescent lamps is FAR better---even old school halophosphate phosphor fluorescent lamps are better in light quality, because the intense blue component of LED (Solid state fluorescent) lamps always is in the near-UV (blacklight) range, and fluoresces the corneas, causing vision distortion. I have NEVER been under any format of "white" LED where this hasn't happened, even if slightly in some cases. the glass tubes of fluorescent lamps filters out most of not all of this near-UV light, and no such effects are seen. I find LED lit places look dim and dismal, and to get the same light levels as the 2 lamp 4 foot T-8 strips, you are forced to go to 4 lamp units, with no savings in energy. And TWICE as many "lamps" to fail, and FAIL they WILL. The directional nature of these LED "tubes" is also annoying as very little "up lighting" of the ceiling occurs, and results in a dark, "cave-like" look to the space, which is very much depressing especially in the winter with getting dark early! LED's always flicker at a high rate, and tend to have a shorter persistence of glow of phosphors, compared to the large phosphor surface of fluorescent lamps, which even at 60 Hz frequency are never objectionable. Only a "rectifying" lamp with one cathode de-activated from sputtering of emission material an is at EOL, and operating literally at 30 Hz, can at all be objectionable in terms of flicker. Also, the strong blue component of LED's that gets through allows the flicker, even at high frequency, to be annoying, causing headaches, seizures in some people, or flares in neurological conditions in people like me who have MS, and are very sensitive. The light that bypasses the phosphors in LED's is the culprit, and switch-mode "drivers" (proper name--BALLASTS!!!) that run LED's are a BAD IDEA. All ya need is a step down transformer (assuming parallel LED operation), a full-wave bridge rectifier, and stabilizing electrolytic capacitors for a smooth DC output. And this set up is WAY more efficient and less lossy than switch-mode, which is part of why LED's aren't very efficient despite the crazy claims manufacturers make. Add to this the degradation of the phosphors in LED lamps, due to the extreme overloading of them, to try to get decent light output, as well as yellowing of the epoxy of the LED's, from the "UV that is claimed not to exist in LED's--LIE!!!!) and you get color-shift, and dimming out, and it accelerates rapidly as they age. I see many CREE "EDGE HO" units rapidly turning green and dimming out after the second year of service as long as the driver doesn't quit. They are not only UGLY fixtures in the highest degree, and ruin the looks of any landscape they are installed in, but they are HORRIBLE PERFORMERS! Also, of LED's and so "efficient", why do they need heat sinks? Yeah, that speaks volumes right there! And these things get HOT--lay your have on one of them (the heat sink) after a few hours of operation and you will let go FAST! J-U-N-K. There are other things, too, but I feel this is sufficient. I know electricians need to get jobs to make money, but scrapping perfectly good older technologies (let's see ANY LED perform as well as and last as long as one of the older, high quality mercury vapor lamps and ballasts! YEAH RIGHT!!!!!!) and even historical fixtures with this JUNK is telling my you guys are DESPERATE to sell this crap to people to make money installing them. The purest form of recycling is re-using older things in good usable condition---I do it all the time with electrical equipment, and there is nothing wrong with it. Ditto on lighting--keep your hands off MY preheat fluorescents and mercury vapor units lighting MY yard and shops etc, PLEASE! LED's SUCK ans are at their peak. They ain't gnna get any better, and in fact will get WORSE as they make them to last as short as incandescents. So quit telling me what YOU want me to hear, because I ain't listenin' and never WILL. Cheers, God Bless, and hope this lets you know this technology is nothing much to get excited over.
 
Seems to me that until manufacturers of LED's can just get them to operate at forward biased DC current instead of messing around with frequencies to drive the LED's, strobing will continue with failures.
 
160916-2405 EDT

Rick Delair:

Some of what you have said is just not true. You need a light meter, a real wattmeter, and then run some experiments.

As an approximation for comparable light output, when comparing new bulbs, an LED uses about 1/6 the input power as compared to an incandescent, and a compact fluorescent about 1/3 the input power compared to an incandescent.

There is light output degraduation with all three types with time of operation. So far I am having good results with LEDs, but I do have some problems.

Your discussion would be much clearer to read if you did some paragraphing.


To Others:

LEDs are inherently a DC device. They only conduct easily in one direction (they are a diode), and they only produce light when current flows in that forward direction.

Electronics are used to drive LEDs to obtain overall high power efficiency.

One can use series capacitors as a moderately efficient means to provide current limiting. Can be very reliable. Causes a poor power factor, but this can be used to compensate for inductive loads.

One can use an inductor for current limiting, but this adds to power factor problems and is not as power efficient as is the capacitor approach.

Both capacitor and inductor current limiters would work very well with a Variac for dimming down to 0 with no problems.

Using a passive current limiter means light output would change with changing source voltage, but not as nonlinear as with incandescent.

A simple form of driver with no major problems is a transformer, bridge rectifier, possibly some filter capacitor to smooth out current, and a series resistor. This is not as power efficient, but is reliable and could reduce 120 Hz modulation of the light intensity.

.
 
Welcome to the forum, Rick.

Rick Delair said:
LED's ate just the latest, greatest fad, and have so many shortcomings it is unreal. Also, the term "LED" is a misnomer for GLS LED's. The PROPER name, though the manufacturers won't say it, is "Solid-state fluorescent" lamps. That's LED's are--FLUORESCENT light sources. Sure, there are the R-G-B LED's that mix the 3 primary colors to get various color temperatures of "white", but, LOL :lol: they do it at efficiencies usually as low or even lower than incandescent! SO, to get a decent efficiency (LED "lamps" or "tubes" will NEVER match the efficiency of fluorescent of HID sources, because of the law that 'many small lamps of ANY type are FAR less efficient than ONE larger lamp of any type---like 6 25 watt incandescent bulbs cannot come CLOSE to the efficiency and light output of ONE 150 watt incandescent bulb though they still draw 150 watts) and this is the killer of reaching true high efficiency in LED lamps! You can buy an 18-watt 4 foot LED "tube" to supposedly replace a 32-watt T-8 or 40-watt T-12 lamp. Sure, it will replace it, but it gives HALF the light output even if it LOOKS as bright. About 1800 lumens for the LED tube versus 3200-3600 lumens for the flourescent lamps. If the LED tube were 32 watts it would almost match the fluorescent lamp. SO---in an installation using 2-lamp open strips, installing LED retrofit lamps or complete fixtures would HALVE the light level. I could install 2 lamp 2 foot 17 watt lamps, spaced with a section of conduit 2 feet long between each fixture to equal the row length the 4 foot continuous-row fixtures made, and get JUST AS MUCH LIGHT as the LED junk. And the quality of light from the fluorescent lamps is FAR better---even old school halophosphate phosphor fluorescent lamps are better in light quality, because the intense blue component of LED (Solid state fluorescent) lamps always is in the near-UV (blacklight) range, and fluoresces the corneas, causing vision distortion. I have NEVER been under any format of "white" LED where this hasn't happened, even if slightly in some cases. the glass tubes of fluorescent lamps filters out most of not all of this near-UV light, and no such effects are seen. I find LED lit places look dim and dismal, and to get the same light levels as the 2 lamp 4 foot T-8 strips, you are forced to go to 4 lamp units, with no savings in energy. And TWICE as many "lamps" to fail, and FAIL they WILL. The directional nature of these LED "tubes" is also annoying as very little "up lighting" of the ceiling occurs, and results in a dark, "cave-like" look to the space, which is very much depressing especially in the winter with getting dark early! LED's always flicker at a high rate, and tend to have a shorter persistence of glow of phosphors, compared to the large phosphor surface of fluorescent lamps, which even at 60 Hz frequency are never objectionable. Only a "rectifying" lamp with one cathode de-activated from sputtering of emission material an is at EOL, and operating literally at 30 Hz, can at all be objectionable in terms of flicker. Also, the strong blue component of LED's that gets through allows the flicker, even at high frequency, to be annoying, causing headaches, seizures in some people, or flares in neurological conditions in people like me who have MS, and are very sensitive. The light that bypasses the phosphors in LED's is the culprit, and switch-mode "drivers" (proper name--BALLASTS!!!) that run LED's are a BAD IDEA. All ya need is a step down transformer (assuming parallel LED operation), a full-wave bridge rectifier, and stabilizing electrolytic capacitors for a smooth DC output. And this set up is WAY more efficient and less lossy than switch-mode, which is part of why LED's aren't very efficient despite the crazy claims manufacturers make. Add to this the degradation of the phosphors in LED lamps, due to the extreme overloading of them, to try to get decent light output, as well as yellowing of the epoxy of the LED's, from the "UV that is claimed not to exist in LED's--LIE!!!!) and you get color-shift, and dimming out, and it accelerates rapidly as they age. I see many CREE "EDGE HO" units rapidly turning green and dimming out after the second year of service as long as the driver doesn't quit. They are not only UGLY fixtures in the highest degree, and ruin the looks of any landscape they are installed in, but they are HORRIBLE PERFORMERS! Also, of LED's and so "efficient", why do they need heat sinks? Yeah, that speaks volumes right there! And these things get HOT--lay your have on one of them (the heat sink) after a few hours of operation and you will let go FAST! J-U-N-K. There are other things, too, but I feel this is sufficient. I know electricians need to get jobs to make money, but scrapping perfectly good older technologies (let's see ANY LED perform as well as and last as long as one of the older, high quality mercury vapor lamps and ballasts! YEAH RIGHT!!!!!!) and even historical fixtures with this JUNK is telling my you guys are DESPERATE to sell this crap to people to make money installing them. The purest form of recycling is re-using older things in good usable condition---I do it all the time with electrical equipment, and there is nothing wrong with it. Ditto on lighting--keep your hands off MY preheat fluorescents and mercury vapor units lighting MY yard and shops etc, PLEASE! LED's SUCK ans are at their peak. They ain't gnna get any better, and in fact will get WORSE as they make them to last as short as incandescents. So quit telling me what YOU want me to hear, because I ain't listenin' and never WILL. Cheers, God Bless, and hope this lets you know this technology is nothing much to get excited over.
Click to expand...

So, tell us how you really feel. but next time use some line breaks; reading a monolithic wall of text is hard to do.
 
Those damn new fangeled machines, man will never fly


latest
 
gar said:
160916-2405 EDT


As an approximation for comparable light output, when comparing new bulbs, an LED uses about 1/6 the input power as compared to an incandescent.


.
Click to expand...
But really LED luminous efficiency is around 20 lumens/watt only, comparable to that of an incandescent bulb, though achieving luminous efficiency of 100 lumens/watt is reported by some labs.
 
160917-0823 EDT

Sahib:

As I previously said run your own experiment. Make sure you use a real wattmeter. Some instruments today that are labeled wattmeter are not real wattmeters. For advertizing or other reasons language clarity is being dumbed down. Accurate communication is not very good if words or grouping of words have too many different meanings. In the past when you bought a wattmeter from Weston or Simpson it was a true wattmeter within the scope of its specifications. There are some devices today labeled wattmeter that may be simply an ammeter or VA meter.

Foot-pounds is a unit of work (energy), not torque, even though many torque wrench manufacturers use the label for torque. The manufacturers are beginning to use the correct labels which are pound-feet, pound-inches, etc. They seem to have always used the correct metric names, newton-meters, etc. There is a direct relationship between torque and work, but it involves time, and torque (rotational force) is an instantaneous value compared to work (energy, force and distance) which is some instantaneous value integrated over time.

.
 
To the LED skpetics: Do you really believe that these problems, real or imagined, are not being presently solved? All the major lighting companies (lamp, luminaire, and ballast) have entire divisions loaded with engineers and scientists who are currently developing and expanding LED products offerings and making them better every day. Every emerging technology will have issues but this one is here to stay, and as such, will continue to improve as the years go by.

Now, I am sympathetic to some of the things you say. For instance, I dislike the throw-away mentality of today's products. It would be nice if everything was well made like it used to be, and lasted for decades. I completely understand the love for longevity with old fluorescent and MV lamps and ballasts. But that stuff is ancient garbage that is wasteful and inefficient despite how long it might last. Furthermore, as I mentioned above, I think great strides will be made in LED longevity that will put the final nail in the coffin of almost obsolete systems.
 
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