Looking at the LED replacement tubes TLC have on offer, I can find no
mention of the life. Except 3 years - which means not a lot to me. They do
have a three year warranty, though. Why is the more usual hours of running
not quoted?

The fluorescent tubes I'm thinking of replacing are more like 20 years
old. Do LEDs self destruct with time? ;-)

--
*It IS as bad as you think, and they ARE out to get you.

Dave Plowman London SW
To e-mail, change noise into sound.

Well, most lighting has a heat issue, particularly semiconductor ones, but
its kind of like how long is a piece of string with lamps like this as they
can fail due to the psu, or individual leds can fail, but this does not
cause a total failure.
Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Dave Plowman (News)" wrote in message
...
Looking at the LED replacement tubes TLC have on offer, I can find no
mention of the life. Except 3 years - which means not a lot to me. They do
have a three year warranty, though. Why is the more usual hours of running
not quoted?

The fluorescent tubes I'm thinking of replacing are more like 20 years
old. Do LEDs self destruct with time? ;-)

--
*It IS as bad as you think, and they ARE out to get you.

Dave Plowman London SW
To e-mail, change noise into sound.

On Thu, 6 Dec 2018 15:37:44 -0000, "Brian Gaff"
wrote:

Well, most lighting has a heat issue, particularly semiconductor ones, but
its kind of like how long is a piece of string with lamps like this as they
can fail due to the psu, or individual leds can fail, but this does not
cause a total failure.
Brian

Not quite. Surely there is a rated life? Although not guaranteed,
the figure quoted should allow comparisons to be made. GLS for
example was always quoted as 1000 hours, which allowed the user to
conclude that the lifetime was (likely to be) shorter than that of a
fluorescent tube.

In article ,
Scott wrote:
On Thu, 6 Dec 2018 15:37:44 -0000, "Brian Gaff"
wrote:

Well, most lighting has a heat issue, particularly semiconductor ones, but
its kind of like how long is a piece of string with lamps like this as they
can fail due to the psu, or individual leds can fail, but this does not
cause a total failure.
Brian

Not quite. Surely there is a rated life? Although not guaranteed,
the figure quoted should allow comparisons to be made. GLS for
example was always quoted as 1000 hours, which allowed the user to
conclude that the lifetime was (likely to be) shorter than that of a
fluorescent tube.

Yes. Florries used to be quoted at something like 10,000 hours - although
output could fall off somewhat in that time.

If they mean 3 years continuous - ie some 26,000 hours - I'd be happy with
that. ;-)

--
*Depression is merely anger without enthusiasm *

Dave Plowman London SW
To e-mail, change noise into sound.

On Thu, 06 Dec 2018 15:54:25 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
Scott wrote:
On Thu, 6 Dec 2018 15:37:44 -0000, "Brian Gaff"
wrote:

Well, most lighting has a heat issue, particularly semiconductor ones, but
its kind of like how long is a piece of string with lamps like this as they
can fail due to the psu, or individual leds can fail, but this does not
cause a total failure.
Brian

Not quite. Surely there is a rated life? Although not guaranteed,
the figure quoted should allow comparisons to be made. GLS for
example was always quoted as 1000 hours, which allowed the user to
conclude that the lifetime was (likely to be) shorter than that of a
fluorescent tube.

Yes. Florries used to be quoted at something like 10,000 hours - although
output could fall off somewhat in that time.

If they mean 3 years continuous - ie some 26,000 hours - I'd be happy with
that. ;-)

You could believe in quoted life for filament and fluorescent, but
semiconductors have completely random lives and are susceptible to
voltage spikes. Users are now punters.
--
Dave W

On 07/12/2018 20:32, Dave W wrote:

You could believe in quoted life for filament and fluorescent,

Was the quoted life for something that was left permanently on or for a
device switched on/off at regular intervals? I suspect the former.

The second hand fluorescent fitting that I installed in my loft space
35+ years ago was still working yesterday - but it's probably only been
switched on a couple of hundred hours during that time


but
semiconductors have completely random lives and are susceptible to
voltage spikes.

How many of your traditional light bulbs failed at the point of switch
on rather than having a gradual end of life? There was a random nature
to the failure associated with traditional filament bulbs due to point
in the voltage waveform at which the switching occurred and as a result
of voltage spikes.

With fluorescent the light intensity fell away but probably it wasn't
noticed until the tubes were replaced and suddenly everything got much
brighter. I also found that the small diameter tubes not only pulsed at
times but the ends became blackened relatively quickly.

While its true that many of the early LED bulbs had a poor reputation
for early life failure in my experience the LEDs I've purchased in the
past couple of years have proved to be reliable. However I have replaced
many old light fittings with LED panel type fittings.


--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

"Brian Gaff" wrote in
news
Well, most lighting has a heat issue, particularly semiconductor ones,
but its kind of like how long is a piece of string with lamps like
this as they can fail due to the psu, or individual leds can fail,
but this does not cause a total failure.
Brian


Why can't the heat sensitive components be designed to cope better?

On 06/12/2018 18:35, DerbyBorn wrote:
"Brian Gaff" wrote in
news
Well, most lighting has a heat issue, particularly semiconductor ones,
but its kind of like how long is a piece of string with lamps like
this as they can fail due to the psu, or individual leds can fail,
but this does not cause a total failure.
Brian


Why can't the heat sensitive components be designed to cope better?

It can. But the tight fisted consumers wont pay the increase in costs.

On 06/12/2018 18:35, DerbyBorn wrote:
"Brian Gaff" wrote in
news
Well, most lighting has a heat issue, particularly semiconductor ones,
but its kind of like how long is a piece of string with lamps like
this as they can fail due to the psu, or individual leds can fail,
but this does not cause a total failure.
Brian


Why can't the heat sensitive components be designed to cope better?

Money


--
€œA leader is best When people barely know he exists. Of a good leader,
who talks little,When his work is done, his aim fulfilled,They will say,
€œWe did this ourselves.€�

ۥ Lao Tzu, Tao Te Ching

On 06/12/2018 19:03, The Natural Philosopher wrote:
On 06/12/2018 18:35, DerbyBorn wrote:
"Brian Gaff" wrote in
news
Well, most lighting has a heat issue, particularly semiconductor ones,
but its kind of like how long is a piece of string with lamps like
this asÂ* they can fail due to the psu, or individualÂ* leds can fail,
but this does not cause a total failure.
Â* Brian


Why can't the heat sensitive components be designed to cope better?

Money


LEDs do not produce heat so that is not a failure mechanism. Mechanical
failure is most likely and I have a new totally enclosed and waterproof
LED lantern which quotes 50000 hours typical life. Not seen the tubes
but the construction must be similar to other LED luminaries with LEDs
spread along the length of the tube. I would expect similar service life.



--
Old Codger
e-mail use reply to field

What matters in politics is not what happens, but what you can make
people believe has happened. [Janet Daley 27/8/2003]

Old Codger brought next idea :
LEDs do not produce heat so that is not a failure mechanism. Mechanical
failure is most likely and I have a new totally enclosed and waterproof LED
lantern which quotes 50000 hours typical life. Not seen the tubes but the
construction must be similar to other LED luminaries with LEDs spread along
the length of the tube. I would expect similar service life.

Actually they do, it is more obvious with the higher wattage versions,
but they do. Their driver circuits generate most of the waste heat,
problem is disposing of the heat - the higher their working
temperature, the shorter their working life.

"Old Codger" wrote in message
news
On 06/12/2018 19:03, The Natural Philosopher wrote:
On 06/12/2018 18:35, DerbyBorn wrote:
"Brian Gaff" wrote in
news
Well, most lighting has a heat issue, particularly semiconductor ones,
but its kind of like how long is a piece of string with lamps like
this as they can fail due to the psu, or individual leds can fail,
but this does not cause a total failure.
Brian


Why can't the heat sensitive components be designed to cope better?

Money

LEDs do not produce heat

The higher power ones do.

so that is not a failure mechanism.

Fraid so.

Mechanical failure is most likely and I have a new totally enclosed and
waterproof LED lantern which quotes 50000 hours typical life. Not seen
the tubes but the construction must be similar to other LED luminaries
with LEDs spread along the length of the tube. I would expect similar
service life.

In article ,
Old Codger wrote:
LEDs do not produce heat so that is not a failure mechanism.

Really? Not seen the size of the heatsink fitted to high power ones like
you'll find in a car headlight?

If it produced no heat, it would be (near) 100% efficient. They're not.

--
*Why is the man who invests all your money called a broker?

Dave Plowman London SW
To e-mail, change noise into sound.

On 06/12/2018 21:38, Old Codger wrote:

LEDs do not produce heat

Yes they do, and likewise the components used in the power supplies.

LED lantern which quotes 50000 hours typical life.

The quoted Life expectancy of LEDs IF they are kept at a temperature of 25C


--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

"DerbyBorn" wrote in message
2.236...
"Brian Gaff" wrote in
news
Well, most lighting has a heat issue, particularly semiconductor ones,
but its kind of like how long is a piece of string with lamps like
this as they can fail due to the psu, or individual leds can fail,
but this does not cause a total failure.
Brian


Why can't the heat sensitive components be designed to cope better?

They can, but that isnt cheap to do with a proper heatsink
and with some stuff like leds which are intended to be a
plug in replacement for an incandescent that didn’t have
a problem with getting hot, not necessarily possible.

On Thursday, 6 December 2018 18:35:43 UTC, DerbyBorn wrote:
"Brian Gaff" wrote in
news
Well, most lighting has a heat issue, particularly semiconductor ones,
but its kind of like how long is a piece of string with lamps like
this as they can fail due to the psu, or individual leds can fail,
but this does not cause a total failure.
Brian


Why can't the heat sensitive components be designed to cope better?

Cost.

In article ,
whisky-dave writes:
On Thursday, 6 December 2018 18:35:43 UTC, DerbyBorn wrote:
"Brian Gaff" wrote in
news
Well, most lighting has a heat issue, particularly semiconductor ones,
but its kind of like how long is a piece of string with lamps like
this as they can fail due to the psu, or individual leds can fail,
but this does not cause a total failure.
Brian


Why can't the heat sensitive components be designed to cope better?

Cost.

and in some cases (particularly the LED itself), physics.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On Friday, 7 December 2018 12:25:21 UTC, Andrew Gabriel wrote:
In article ,
whisky-dave writes:
On Thursday, 6 December 2018 18:35:43 UTC, DerbyBorn wrote:
"Brian Gaff" wrote in
news
Well, most lighting has a heat issue, particularly semiconductor ones,
but its kind of like how long is a piece of string with lamps like
this as they can fail due to the psu, or individual leds can fail,
but this does not cause a total failure.
Brian


Why can't the heat sensitive components be designed to cope better?

Cost.

and in some cases (particularly the LED itself), physics.


https://www.youtube.com/watch?v=h-UoYVBFRPQ


or just blow on it a little harder that should cool it ;-)


--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

In article ,
Andrew Gabriel wrote:
In article ,
whisky-dave writes:
On Thursday, 6 December 2018 18:35:43 UTC, DerbyBorn wrote:
"Brian Gaff" wrote in
news
Well, most lighting has a heat issue, particularly semiconductor ones,
but its kind of like how long is a piece of string with lamps like
this as they can fail due to the psu, or individual leds can fail,
but this does not cause a total failure.
Brian


Why can't the heat sensitive components be designed to cope better?

Cost.

and in some cases (particularly the LED itself), physics.


The answer in my case (converting existing basic florries) would be to rip
out the ballasts etc and replace them with proper LED drivers. Keeping
that part clear of the LEDs themselves. If such a kit of drivers and tubes
existed.

--
*Why are a wise man and a wise guy opposites?

Dave Plowman London SW
To e-mail, change noise into sound.

On 06/12/2018 18:35, DerbyBorn wrote:
"Brian Gaff" wrote in
news
Well, most lighting has a heat issue, particularly semiconductor ones,
but its kind of like how long is a piece of string with lamps like
this as they can fail due to the psu, or individual leds can fail,
but this does not cause a total failure.
Brian


Why can't the heat sensitive components be designed to cope better?


The problem is often the light fitting itself and not necessarily the
components you fit into it.

If you fit any of any kind of bulb in a recessed downlighter fitting
then expect it to get hot as there is often insufficient free air
ventilation. Replace your fitting for something well designed for LEDs
then you stand a better chance of obtaining long life.

The OP is looking for replacement tubes and they are more likely to run
cool in tat kind of fitting.

Some designs of LED light power supplies do take heat into consideration
by monitoring the temperature and reducing the current to the LED when
it starts getting too hot. This also will reduce the light output.
Unfortunately it is virtually impossible to tell what kind of power
conditioning has been used in most LED lights without stripping it down
(and probably destroying it)

--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

Dave Plowman wrote:

Looking at the LED replacement tubes TLC have on offer, I can find no
mention of the life.

Their 4,000 lumen daylight ones quote 30,000 hours

https://www.tlc-direct.co.uk/Products/LTTH527DL.html

Though you were holding out for better than CRI90?

Andy Burns wrote:

Though you were holding out for better than CRI90?

typo, better than 80

Just generally curious, since I see a lot of posts expressing concern about LED bulb life, actual and expected. I have yet to have one fail on me. The oldest ones in my house are from about 8 years ago, when I did a bathroom refit. The bathroom in question is the main bathroom, so lots of daily use and some extended periods of artificial illumination.

Have I simply been lucky? I'd guess I have 15 or so LED bulbs in use.

Ant.

wrote

Just generally curious, since I see a lot of posts expressing
concern about LED bulb life, actual and expected. I have
yet to have one fail on me. The oldest ones in my house
are from about 8 years ago, when I did a bathroom refit.
The bathroom in question is the main bathroom, so lots of
daily use and some extended periods of artificial illumination.

Have I simply been lucky?

Yes you have. There are reports in our local forum
that some of the ones Aldi sell dont last that long.

I'd guess I have 15 or so LED bulbs in use.

Andy Burns wrote:

Their 4,000 lumen daylight ones quote 30,000 hours

And the .PDF datasheets for the other lengths/wattages say the same.

Andy Burns wrote:

Their 4,000 lumen daylight ones quote 30,000 hours

I had an IKEA lamp fail, and by the time I visited to return it a
couple of years had elapsed since purchase. They initially were
disinclined to allow a refund, suggesting that I could have had
it on permanently.

I asked how the maths for that worked, which they didn't want to
share, and after further consultation they "made an exception"
and refunded me.

Chris
--
Chris J Dixon Nottingham UK


Plant amazing Acers.

On Thu, 06 Dec 2018 14:02:36 +0000 (GMT), "Dave Plowman (News)"
wrote:

Looking at the LED replacement tubes TLC have on offer, I can find no
mention of the life. Except 3 years - which means not a lot to me. They do
have a three year warranty, though. Why is the more usual hours of running
not quoted?

The fluorescent tubes I'm thinking of replacing are more like 20 years
old. Do LEDs self destruct with time? ;-)

3350lm for a 5 footer and a claimed 133lm/W appears good and at around £8+vat
they are cheap.

Maybe too good and too cheap? Their 330 degrees of beam angle will also be
wasted somewhat in many fluoroscent fittings. Without correct heat management
the output could be down the pan in a few years.

Osram do complete enclosed IP65 luminaires 5ft, 55W, 6500lm, 115lm/W with a 180
deg beam angle for 50 quid + vat with a 5 year guarantee (available from CPC)

--