LED GLS bulbs

[Robin GrahamParticipant @robingraham42208]

Has anyone found a brand of LED GLS bulbs which last anything like the the 25 – 30,000 hours burn time which is commonly advertised? I think my record is about 9 months, so I must burn them for over 100 hours a day.

I've bought cheapo Wilko bulbs, mid range from Screwfix, pricier Phillips and Osram but they all fail well before the advertised MTBF. The only advantage I've noticed with the 'big name' brands is that they seem brighter than the cheapos with the same advertised lumens / colour temperature. In all the brands I've tried there is quite a big spread (in the same brand/model) between lamps which fail very early and those which last longer.

I'm not really complaining – still saving money, but I'd like to know more. Does anyone know how these lamps typically fail? The LEDs themselves, or the drivers?

Robin.

Edited By Robin Graham on 04/07/2020 23:46:15

[Robin GrahamParticipant @robingraham42208]

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Robin Graham on 04/07/2020 23:45:28:

[…]

Does anyone know how these lamps typically fail? The LEDs themselves, or the drivers?

Robin.

.

I don’t have sufficient data to assert that it’s typical, but a recent failure resulted in two visibly burnt LEDs in the array [one of which went open-circuit]. A replacement lamp also quickly failed … and I am convinced both failures were caused by a poor quality light-switch.

Swapped the switch for a good MK one with a nice crisp action, and all has been well.

MichaelG.

[John OlsenParticipant @johnolsen79199]

My experience suggests that it is usually the little power supply that fails. I suppose they would argue that the light itself is still fine….

John

[Ady1Participant @ady1]

It's maybe the voltage that kills them

I've been running a little 3xAA battery camping light 24/7 for 4 years as a night light in the hall, batteries get done about every 5 months

240v LED Bulbs in use a lot go from 3 months to a few years

[Sam StonesParticipant @samstones42903]

No promises that you'll get your answer directly, although I'm sure you'll find Big Clive both informative and entertaining. He specialises in using reverse engineering and many other ways to reveal faults.

Lighting and associated electronics is one of his particular skills.

However, you might have to wade through his many videos.

**LINK**

Sam

 

Edited By Sam Stones on 05/07/2020 01:14:08

[Harry WilkesParticipant @harrywilkes58467]

Posted by Michael Gilligan on 05/07/2020 00:00:43:

Posted by Robin Graham on 04/07/2020 23:45:28:

[…]

Does anyone know how these lamps typically fail? The LEDs themselves, or the drivers?

Robin.

.

I don’t have sufficient data to assert that it’s typical, but a recent failure resulted in two visibly burnt LEDs in the array [one of which went open-circuit]. A replacement lamp also quickly failed … and I am convinced both failures were caused by a poor quality light-switch.

Swapped the switch for a good MK one with a nice crisp action, and all has been well.

MichaelG.

Michael had the same result as yourself by changing the light switch, my Uncle had a problem with a LED light eating 'bulbs' I couldn't find anything wrong with either the fitting or the supply but after another failure I changed the light switch now several months later no more failures

H

[Ady1Participant @ady1]

So is that the startup surge killing the driver?

and is it the power supply or the led that fails?

led components

So the light filament (the LED) is fine and nowadays the power pack/driver fails, lol, they always find a way to gouge the customer

So if you want a "forever" system get a low voltage lighting system

What about a 12v boat or car LED system, are they more reliable

Edited By Ady1 on 05/07/2020 08:07:26

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Ady1 on 05/07/2020 08:01:51:

So is that the startup surge killing the driver?

and is it the power supply or the led that fails?

 

.

No … The driver seems to survive, but I think the bad switch contacts are acting as a diode for a few mains-cyles: de-stabilising the driver and over-driving the LEDs.

To quote my previous post: … a recent failure resulted in two visibly burnt LEDs in the array [one of which went open-circuit].

For the avoidance of doubt; that’s two LED chips in the array within a single ‘mains light bulb’

MichaelG.

Edited By Michael Gilligan on 05/07/2020 08:31:12

[SamsarandaParticipant @samsaranda]

Have no problems with led life but changed all our light switches for MK a few years ago as we redecorated each room, I always go for the quality option where electrics are concerned, I got fed up with cheapo switches arcing when switched, you can’t put a price on safety.
Dave W

[Peter G. ShawParticipant @peterg-shaw75338]

My experience of both LED's & CFL's is, to say the least, poor.

We have a Philips CFL in the hall which was a "free" gift dating back to when we had wall insulation installed back in 1995. That light is still working ok. I can't comment on its light output after all these years.

We have had some Osram CFL's which seem ok, but on the other hand, we have had Megaman or whatever which frankly don't last.

Lately, we bought three of the highest power LED's that we could find for use in our back room which due to the kitchen extension is a dark room at the best of times. These LED's, plus two replacements, failed by flashing (no, not by us, the electronics started flashing). Replacement by a slightly lower power set by Crompton and they now seem ok. We still have one of the original higher power LED working ok, but I do have a spare Crompton waiting for use.

Light Switches. All of ours were changed at the same time back in 1995 for Volex switches. As some lights are satisfactory, then in general, I would tend to rule out switching problems. My personal thoughts are that the "cheaper", ie lesser known brands, have problems with the heat generated by the electronics whilst the better known brands, Osram, Phillips, Crompton can cope with this heat. Very subjective, I know, but those are my thoughts.

Peter G. Shaw

[Oven ManParticipant @ovenman]

Posted by Michael Gilligan on 05/07/2020 08:27:49:

Posted by Ady1 on 05/07/2020 08:01:51:

So is that the startup surge killing the driver?

and is it the power supply or the led that fails?

.

No … The driver seems to survive, but I think the bad switch contacts are acting as a diode for a few mains-cyles: de-stabilising the driver and over-driving the LEDs.

To quote my previous post: … a recent failure resulted in two visibly burnt LEDs in the array [one of which went open-circuit].

For the avoidance of doubt; that’s two LED chips in the array within a single ‘mains light bulb’

MichaelG.

Edited By Michael Gilligan on 05/07/2020 08:31:12

My experience has been almost the exact opposite, the driver fails not the LED. Being the nerd that I am I usually pull failed items apart to see why they have failed. I have a collection of LED chips that work OK, just need to find a use for them. Some of them are series connected and need quite a few volts to drive them. About 20 years ago I replaced the filament lamp in our door bell push with an LED and it has worked perfectly ever since, still as bright as the day it was installed. As with a lot of consumer products the components are pushed right up to their design limits so it's probably not surprising that we see so many failures. Cost also dictates that high temperature rated components are a nono. As I mentioned in a previous thread it appears that manufactures guarantee the LED for x years but not the complete bulb. Has anyone tried getting them replaced under guarantee?

Peter

[Andrew TinsleyParticipant @andrewtinsley63637]

For what it is worth. The lifetime of an LED is critically dependent on the ambient temperature. Get too many in a localised volume and the lifetime drops very rapidly Good LED bulbs have a very efficient heatsinks. As for drivers depends on the design and quality of components.

Andrew.

[Peter G. ShawParticipant @peterg-shaw75338]

Oven Man/Peter.

As mentioned above, I bought 3 highpower LED's – these had a 5 year warranty. Two were changed under warranty – then the shop closed down! After that, another two failed again, same problem, flashing on/off. Of these, one was tested elsewhere and continued flashing so dumped, whilst the other appears ok (so far) in an open fitting, ie no lampshade to hold in the heat.

The replacement Cromptons have a 3 year warranty.

(Another) Peter G. Shaw

[KWILParticipant @kwil]

Standard old fashioned GLS lamps still working for me.

[CirclipParticipant @circlip]

I'm banking on the driver. Have a 64 chip one in the bathroom which after about a minute, half go out. On switching off waiting a couple of minutes and back on again, same thing happens. Have rotated the lamp through 180 deg. in socket and original side goes out.

Regards Ian.

[Steve Skelton 1Participant @steveskelton1]

The thing that causes the most damage to an LED is running temperature. You will find most of the good quality high power units have a heatsink on the LED itself.

I have been on an Osram training course on the use and installation of LED's and they were very adamant that keeping the LED cool is critical and when they get hot they cook themselves and the light output is vastly reduced before they fail. Very similar to CFL's in that respect.

When you install LEDs consider where they are going and how to keep a flow of cooling air around them, otherwise LED's are a false economy.

By the same token drivers should be matched to the LED's they are powering for obvious reasons.

Ooops Andrew – missed your post!!

Steve

Edited By Steve Skelton 1 on 05/07/2020 12:02:30

[GeorgineerParticipant @georgineer]

Robin, I suspect that the manufacturers would hide behind the 'M' in MTBF. As in "Yes, this one failed well before the mean time, but what about all the ones which go well beyond that time? Do you keep a record of them?"

I have had trouble with two Philips LED bulbs which emit an intrusive whistle, presumably from an internal switched-mode power supply. I have had to withdraw them from use because the whistle was irritating me beyond endurance.

George B.

[Michael GilliganParticipant @michaelgilligan61133]

Just to keep the conversation going … here are some pictures of my failed ‘flying saucer’

The two burned LEDs are clearly identifiable:

.

.

.

MichaelG.

[Robin GrahamParticipant @robingraham42208]

Thanks for replies. Reading MichaelG's and other respondents' suggestions that it may be the the switch that's the problem I remembered that I have a 4W LED bulb lighting the stairwell down to my cellar workshop. It's been burning 24/7 for over a year – I've become so used to it that I forget it's there. I installed it as a 'temporary' replacement for a PIR LED lamp which failed within 6 months, So maybe it is to do with switching – though obviously the switching in a PIR must be rather different from a normal light switch, presumably solid state. Hmm. The specs for the bulbs I've had claim 100,000 switching cycles, so I'd assumed that switching wasn't an issue.

Sam – thanks for the link to Big Clive – I'll have a wade.

George – I take your point, but in my (admittedly small) sample I haven't yet had a bulb to the right hand side of the mean.

Since my original post I have discovered that 12V (presumably DC) LED bulbs are available in GLS form. Is there any reason why I shouldn't disconnect the 240V house lighting circuit from the MCB and run the house lighting from a 12V power supply though existing wiring? The upstairs and downstairs have independent circuits wired with 1.5mm cable, which is good for 10A I believe.So 120W for each floor, which might be liveable with given LED efficiency.

Robin.

 

Edited By Robin Graham on 06/07/2020 00:28:29

Edited By Robin Graham on 06/07/2020 00:29:11

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Robin Graham on 06/07/2020 00:20:07:

[…]

Since my original post I have discovered that 12V (presumably DC) LED bulbs are available in GLS form. Is there any reason why I shouldn't disconnect the 240V house lighting circuit from the MCB and run the house lighting from a 12V power supply though existing wiring? The upstairs and downstairs have independent circuits wired with 1.5mm cable, which is good for 10A I believe.So 120W for each floor, which might be liveable with given LED efficiency.

Robin.

 

.

That might be a good move, Robin

I will also just mention, in passing, that some 12V LED lamps have bridge rectifiers built-in, and can therefore be safely inserted either way round, or even used on low voltage AC [with the attendant risk of visible flicker].
The ones I have are MR16 fit, but there may well be other styles available.

MichaelG.

.

Edit: this might be a useful place to start your investigation:

https://blog.lightbulbs-direct.com/replacing-halogen-mr16s-with-leds/

… Be sure to read the comments though … it can be trickier than the advice suggests

Edited By Michael Gilligan on 06/07/2020 07:57:04

[Michael KertonParticipant @michaelkerton45997]

Posted by Oven Man on 05/07/2020 10:13:27:

Posted by Michael Gilligan on 05/07/2020 08:27:49:

Posted by Ady1 on 05/07/2020 08:01:51:

So is that the startup surge killing the driver?

and is it the power supply or the led that fails?

.

No … The driver seems to survive, but I think the bad switch contacts are acting as a diode for a few mains-cyles: de-stabilising the driver and over-driving the LEDs.

To quote my previous post: … a recent failure resulted in two visibly burnt LEDs in the array [one of which went open-circuit].

For the avoidance of doubt; that’s two LED chips in the array within a single ‘mains light bulb’

MichaelG.

Edited By Michael Gilligan on 05/07/2020 08:31:12

My experience has been almost the exact opposite, the driver fails not the LED. Being the nerd that I am I usually pull failed items apart to see why they have failed. I have a collection of LED chips that work OK, just need to find a use for them. Some of them are series connected and need quite a few volts to drive them. About 20 years ago I replaced the filament lamp in our door bell push with an LED and it has worked perfectly ever since, still as bright as the day it was installed. As with a lot of consumer products the components are pushed right up to their design limits so it's probably not surprising that we see so many failures. Cost also dictates that high temperature rated components are a nono. As I mentioned in a previous thread it appears that manufactures guarantee the LED for x years but not the complete bulb. Has anyone tried getting them replaced under guarantee?

Peter

I had some Screwfix LED failures. The catalogue advertising blurb claimed if I recall, 30,000 hours, but they failed within six months. Manager refused to replace them as they only replace duff items withing 30 days. I complained to HQ and pointed out the consumer rights legislation. These lamps were not as described E.G 30,000 hours and were not fit for purpose . Anyhow, they replaced the lamps, eventually. LEDs dont like heat, so its a good idea to be selective about the fitting they go in to. A sealed bathroom globe might not be an ideal environment for LEDs!

As for inrush current destroying the electronics, I like to shove a thermister in series. It just takes out the hard knock on switch on.

Regards

Michael

[Steve Skelton 1Participant @steveskelton1]

Robin, as a retired NECEIC Qualified Supervisor (in my many roles in business) I would strongly advise against converting the existing 230Vac circuit to a 12V circuit.

Both voltage types can be run in a property but there are strict controls of circuit separation which are unlikely to be present (assuming the circuits are built into the house structure) unless the circuit was designed in this way from when it was installed. You would need to use a qualified electrician to carry out a thorough investigation (including instrumental testing to ensure adequate insulation resistance) and get the circuit signed off as safe for use with a lower voltage. I regularly came across instances of separate circuits in the same enclosure which could easily be confused and could be mistakenly interconnected with obvious results. If I had been asked to certify what you propose I would be very wary of doing it.

If however, your circuit is surface run and/or can easily be separated from the existing 230Vac circuits then there will be no problem.

I would also be wary regarding your house insurance of doing something like that as well in case something did happen.

By the way, GLS LED versions have built-in circuitry to allow them to run on 230Vac

If you are using quality components (ie switches, power supplies (if needed) and LED light units then you should not be experiencing problems. As the current demand for LEDs is significantly lower than was previously used the light switch contacts may be your problem as the currents now being used will not be self-cleaning and will not clean high resistance contacts. As Michael suggested you could try replacing your switches use good clean contact switches. Poor contact switches could be continually arcing at the currents involved.

Steve

[John HaineParticipant @johnhaine32865]

The common Ikea Janszo light gives problems after a year or two because the fitted switch, which just used a non-toggling contact, becomes intermittent. I have replaced a couple of these with a proper in-line switch with a good click action. I can imagine that if the switch is on the HV side where current is a lot lower the problem would be worse. But why an intermittent contact should damage a well-designed inverter I can't see.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by John Haine on 06/07/2020 10:16:17:

[…]

But why an intermittent contact should damage a well-designed inverter I can't see.

.

I may be missing your point, John [in which case, please accept my apologies], but:

My hypothesis was not that the contact was intermittent, but that it was [briefly] diodic in nature

[ Steve’s comment about self-cleaning is relevant ]

The replacement lamp on that circuit was perceptibly ‘slow to start’ until I changed the switch.

I don’t have the skill or enthusiasm to properly test the hypothesis, but I am fairly confident that the driver circuit was imbalanced [and therefore produced a spikey output] for a few mains cycles immediately after switch-on … no harm done to the driver, but over-voltage on the LEDs.

My photo shows the two weak links in the chain.

.

Click image to enlarge

MichaelG.

Edited By Michael Gilligan on 06/07/2020 11:35:31

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