We have several mains voltage LED downlighters and a couple have taken
to turning off after they've been on for a while and then turning back
on after a couple of minutes.

It would seem that something is overheating perhaps? Is it likely to be
the transformer or the lamp?

--
Frank

On 1/26/2024 6:30 PM, Frank wrote:
> We have several mains voltage LED downlighters and a couple have taken to turning off after they've been on for a while and then turning back on after a couple of minutes.
>
> It would seem that something is overheating perhaps? Is it likely to be the transformer or the lamp?
>

LED lamps and the SMPS in the base, really could use some airflow.

This is why it is not recommended to place them in sealed globes,
such as the globe in my kitchen.

https://www.ledsmagazine.com/leds-ssl-design/thermal/article/16695318/accurate-thermal-simulation-enables-led-lighting-products-to-match-design-goals-magazine

While you could punch a hole in the top of a pot to allow the
hot air to escape, that might be a violation of a fire code.
I don't know the rules regarding modifications like that.

In any case, pots were designed for incandescents, and the ceramic
and metal in incandescent bulbs can take lots of heat. Relatively speaking.

They make LEDs on silicon carbide substrates, to extend the temperature
range, but the problem is, some of the environments are just too miserable
for such incremental improvements to help a lot. The article above mentions
the electrolytic capacitor failing, and sometimes when the lamp dies in only
three months, it's the cap that fried, not the LEDs. The capacitor might only
be rated for 2000 hours at that temperature.

In the SMPS controller chip, it is easy to add an overtemperature detector,
as substrate diodes are easy to do in silicon. It could be purposely
switching off, or, the SMPS oscillator could have stopped switching for
some reason.

It you take the lamp out of the pot and operate it in open
air on your table, I bet it will run all day long without
winking out.

I have some lamps here, that are failing prematurely, and they *do*
have airflow. And that's how you know, how "cheerful" LEDs have become.

Paul

Paul <nospam@needed.invalid> wrote
> Frank wrote

>> We have several mains voltage LED downlighters and acouple have taken
>> to turning off after they've been on fora while and then turning back
>> on after a couple of minutes.

>> It would seem that something is overheating perhaps?Is it likely to
>> be the transformer or the lamp?

Much more likely to be the 'transformer' which isnt actually a transformer.

> LED lamps and the SMPS in the base, really could use some airflow.

None of my Philips Hues need that. Not even
warm even when the room temp is 48C

> This is why it is not recommended to place themin sealed globes, such
> as the globe in my kitchen.

Works fine with the best bulbs.

> https://www.ledsmagazine.com/leds-ssl-design/thermal/article/16695318/accurate-thermal-simulation-enables-led-lighting-products-to-match-design-goals-magazine

> While you could punch a hole in the top of a pot to allowthe hot air to
> escape, that might be a violation of a fire code.
> I don't know the rules regarding modifications like that.

> In any case, pots were designed for incandescents, and the ceramic
> and metal in incandescent bulbs can take lots of heat. Relatively
> speaking.

> They make LEDs on silicon carbide substrates, to extend the temperature
> range, but the problem is, some of the environments are just too
> miserable
> for such incremental improvements to help a lot. The article above
> mentions
> the electrolytic capacitor failing, and sometimes when the lamp dies in
> only
> three months, it's the cap that fried, not the LEDs. The capacitor might
> only
> be rated for 2000 hours at that temperature.

But a failure of those wouldnt see the light cycle.

> In the SMPS controller chip, it is easy to add an overtemperature
> detector,
> as substrate diodes are easy to do in silicon. It could be purposely
> switching off,

Not aware of any that do that and its unlikely
to have just started doing that now, in winter.

> or, the SMPS oscillator could havestopped switching for some reason.

> It you take the lamp out of the pot and operate it in open
> air on your table, I bet it will run all day long without
> winking out.

> I have some lamps here, that are failing prematurely, and they *do*
> have airflow. And that's how you know, how "cheerful" LEDs have become.

On 27/01/2024 00:16, Paul wrote:
> On 1/26/2024 6:30 PM, Frank wrote:
>> We have several mains voltage LED downlighters and a couple have taken to turning off after they've been on for a while and then turning back on after a couple of minutes.
>>
>> It would seem that something is overheating perhaps? Is it likely to be the transformer or the lamp?
>>
>
> LED lamps and the SMPS in the base, really could use some airflow.
>
> This is why it is not recommended to place them in sealed globes,
> such as the globe in my kitchen.
>
> https://www.ledsmagazine.com/leds-ssl-design/thermal/article/16695318/accurate-thermal-simulation-enables-led-lighting-products-to-match-design-goals-magazine
>
> While you could punch a hole in the top of a pot to allow the
> hot air to escape, that might be a violation of a fire code.
> I don't know the rules regarding modifications like that.
>
> In any case, pots were designed for incandescents, and the ceramic
> and metal in incandescent bulbs can take lots of heat. Relatively speaking.
>
> They make LEDs on silicon carbide substrates, to extend the temperature
> range, but the problem is, some of the environments are just too miserable
> for such incremental improvements to help a lot. The article above mentions
> the electrolytic capacitor failing, and sometimes when the lamp dies in only
> three months, it's the cap that fried, not the LEDs. The capacitor might only
> be rated for 2000 hours at that temperature.
>
> In the SMPS controller chip, it is easy to add an overtemperature detector,
> as substrate diodes are easy to do in silicon. It could be purposely
> switching off, or, the SMPS oscillator could have stopped switching for
> some reason.
>
> It you take the lamp out of the pot and operate it in open
> air on your table, I bet it will run all day long without
> winking out.
>
> I have some lamps here, that are failing prematurely, and they *do*
> have airflow. And that's how you know, how "cheerful" LEDs have become.
>
> Paul
Thanks, but there's no pots involved. They're open to the void above the
ceiling and below the roof which is why I'm not sure if it is
overheating and, if it is, which component, lamp or transformer is the
problem.

--
Frank

On 1/26/2024 7:40 PM, Frank wrote:

> Thanks, but there's no pots involved. They're open to the void above the ceiling and below the roof which is why I'm not sure if it is overheating and, if it is, which component, lamp or transformer is the problem.
>

How much power do the LEDs use, compared to the original lights ?

With a multimeter, check the voltage across the LEDs.
In other words, what is the transformer producing right now.
Is the output normal or abnormal ?

You can try substituting one legacy incandescent for one of the
LEDs, and see if stability improves. (This would be an attempt
to alter the power factor of the load presented to the transformer.)

Paul

Frank wrote:

> We have several mains voltage LED downlighters and a couple have taken
> to turning off after they've been on for a while and then turning back
> on after a couple of minutes.

cooked capacitors as a first guess ...

On Sat, 27 Jan 2024 19:20:21 +1100, Andy Burns <usenet@andyburns.uk> wrote:

> Frank wrote:
>
>> We have several mains voltage LED downlighters and a couple have taken
>> to turning off after they've been on for a while and then turning back
>> on after a couple of minutes.
>
> cooked capacitors as a first guess ...

They dont normally work intermittently like that.

On Sat, 27 Jan 2024 11:38:10 +1100, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

<FLUSH the abnormal trolling senile cretin's latest trollshit unread>

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MID: <ogoa38$pul$1@news.mixmin.net>

On Sat, 27 Jan 2024 19:44:53 +1100, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

<FLUSH the abnormal trolling senile cretin's latest trollshit unread>

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your unwanted guff here."
MID: <c1pqvgte5ldlo1rn3fpl7igtg4h8i9mk7p@4ax.com>

You could try swapping them with ones that don't do it to see if the fault
moves with the bulb. That should show what the issue is.
How hot does the lamp or other components get?Normally LED lamps just die
and stay dead if its their internal psu.
Brian

--

--:
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The Sofa of Brian Gaff...
briang1@blueyonder.co.uk
Blind user, so no pictures please
Note this Signature is meaningless.!
"Paul" <nospam@needed.invalid> wrote in message
news:up1i0t$32s83$1@dont-email.me...
> On 1/26/2024 6:30 PM, Frank wrote:
>> We have several mains voltage LED downlighters and a couple have taken to
>> turning off after they've been on for a while and then turning back on
>> after a couple of minutes.
>>
>> It would seem that something is overheating perhaps? Is it likely to be
>> the transformer or the lamp?
>>
>
> LED lamps and the SMPS in the base, really could use some airflow.
>
> This is why it is not recommended to place them in sealed globes,
> such as the globe in my kitchen.
>
>
> https://www.ledsmagazine.com/leds-ssl-design/thermal/article/16695318/accurate-thermal-simulation-enables-led-lighting-products-to-match-design-goals-magazine
>
> While you could punch a hole in the top of a pot to allow the
> hot air to escape, that might be a violation of a fire code.
> I don't know the rules regarding modifications like that.
>
> In any case, pots were designed for incandescents, and the ceramic
> and metal in incandescent bulbs can take lots of heat. Relatively
> speaking.
>
> They make LEDs on silicon carbide substrates, to extend the temperature
> range, but the problem is, some of the environments are just too miserable
> for such incremental improvements to help a lot. The article above
> mentions
> the electrolytic capacitor failing, and sometimes when the lamp dies in
> only
> three months, it's the cap that fried, not the LEDs. The capacitor might
> only
> be rated for 2000 hours at that temperature.
>
> In the SMPS controller chip, it is easy to add an overtemperature
> detector,
> as substrate diodes are easy to do in silicon. It could be purposely
> switching off, or, the SMPS oscillator could have stopped switching for
> some reason.
>
> It you take the lamp out of the pot and operate it in open
> air on your table, I bet it will run all day long without
> winking out.
>
> I have some lamps here, that are failing prematurely, and they *do*
> have airflow. And that's how you know, how "cheerful" LEDs have become.
>
> Paul

If an Led power supply gets hot its hardly being very efficient is it? Are
these all the same maker etc? I remember also aperson telling me that the
colour temp of some supposedly the same leds can be different, indeed
variations exist inside one light. I've never chopped one to bits to see
what is there, but you can bet they have cut out all unrequited parts and
used the cheapest chips and Leeds they can get.
Brian

--

--:
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Blind user, so no pictures please
Note this Signature is meaningless.!
"Rod Speed" <rod.speed.aaa@gmail.com> wrote in message
news:op.2h6j1wukbyq249@pvr2.lan...
> Paul <nospam@needed.invalid> wrote
>> Frank wrote
>
>>> We have several mains voltage LED downlighters and acouple have taken
>>> to turning off after they've been on fora while and then turning back
>>> on after a couple of minutes.
>
>>> It would seem that something is overheating perhaps?Is it likely to be
>>> the transformer or the lamp?
>
> Much more likely to be the 'transformer' which isnt actually a
> transformer.
>
>> LED lamps and the SMPS in the base, really could use some airflow.
>
> None of my Philips Hues need that. Not even
> warm even when the room temp is 48C
>
>> This is why it is not recommended to place themin sealed globes, such
>> as the globe in my kitchen.
>
> Works fine with the best bulbs.
>
>>
>> https://www.ledsmagazine.com/leds-ssl-design/thermal/article/16695318/accurate-thermal-simulation-enables-led-lighting-products-to-match-design-goals-magazine
>
>> While you could punch a hole in the top of a pot to allowthe hot air to
>> escape, that might be a violation of a fire code.
>> I don't know the rules regarding modifications like that.
>
>> In any case, pots were designed for incandescents, and the ceramic
>> and metal in incandescent bulbs can take lots of heat. Relatively
>> speaking.
>
>> They make LEDs on silicon carbide substrates, to extend the temperature
>> range, but the problem is, some of the environments are just too
>> miserable
>> for such incremental improvements to help a lot. The article above
>> mentions
>> the electrolytic capacitor failing, and sometimes when the lamp dies in
>> only
>> three months, it's the cap that fried, not the LEDs. The capacitor might
>> only
>> be rated for 2000 hours at that temperature.
>
> But a failure of those wouldnt see the light cycle.
>
>> In the SMPS controller chip, it is easy to add an overtemperature
>> detector,
>> as substrate diodes are easy to do in silicon. It could be purposely
>> switching off,
>
> Not aware of any that do that and its unlikely
> to have just started doing that now, in winter.
>
>> or, the SMPS oscillator could havestopped switching for some reason.
>
>> It you take the lamp out of the pot and operate it in open
>> air on your table, I bet it will run all day long without
>> winking out.
>
>> I have some lamps here, that are failing prematurely, and they *do*
>> have airflow. And that's how you know, how "cheerful" LEDs have become.

Could just be a dry joint of course or a faulty device where the wire loses
connection inside the plastic. Many years ago a N1501 VCR randomly stopped.
Several people failed to find it, but I used my brain and fond the problem
almost immediately. Four silicon rectifiers in a bridge. Two oof which had
the external wires only making contact by mere luck. Take them out and the
wire fell out. I changed the lot and no more problems. They were Philips
light blue bodied bullet shaped and the wires, in my view had been bent too
close to the flat end of the body.
In such a confined space as a lamp I could well imagine something similar.
Brian

--

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Note this Signature is meaningless.!
"Frank" <home@nowhere.me> wrote in message
news:jzednTQFN6N9zSn4nZ2dnZfqn_EAAAAA@brightview.co.uk...
> On 27/01/2024 00:16, Paul wrote:
>> On 1/26/2024 6:30 PM, Frank wrote:
>>> We have several mains voltage LED downlighters and a couple have taken
>>> to turning off after they've been on for a while and then turning back
>>> on after a couple of minutes.
>>>
>>> It would seem that something is overheating perhaps? Is it likely to be
>>> the transformer or the lamp?
>>>
>>
>> LED lamps and the SMPS in the base, really could use some airflow.
>>
>> This is why it is not recommended to place them in sealed globes,
>> such as the globe in my kitchen.
>>
>>
>> https://www.ledsmagazine.com/leds-ssl-design/thermal/article/16695318/accurate-thermal-simulation-enables-led-lighting-products-to-match-design-goals-magazine
>>
>> While you could punch a hole in the top of a pot to allow the
>> hot air to escape, that might be a violation of a fire code.
>> I don't know the rules regarding modifications like that.
>>
>> In any case, pots were designed for incandescents, and the ceramic
>> and metal in incandescent bulbs can take lots of heat. Relatively
>> speaking.
>>
>> They make LEDs on silicon carbide substrates, to extend the temperature
>> range, but the problem is, some of the environments are just too
>> miserable
>> for such incremental improvements to help a lot. The article above
>> mentions
>> the electrolytic capacitor failing, and sometimes when the lamp dies in
>> only
>> three months, it's the cap that fried, not the LEDs. The capacitor might
>> only
>> be rated for 2000 hours at that temperature.
>>
>> In the SMPS controller chip, it is easy to add an overtemperature
>> detector,
>> as substrate diodes are easy to do in silicon. It could be purposely
>> switching off, or, the SMPS oscillator could have stopped switching for
>> some reason.
>>
>> It you take the lamp out of the pot and operate it in open
>> air on your table, I bet it will run all day long without
>> winking out.
>>
>> I have some lamps here, that are failing prematurely, and they *do*
>> have airflow. And that's how you know, how "cheerful" LEDs have become.
>>
>> Paul
> Thanks, but there's no pots involved. They're open to the void above the
> ceiling and below the roof which is why I'm not sure if it is overheating
> and, if it is, which component, lamp or transformer is the problem.
>
> --
> Frank
>
>

On 27/01/2024 00:38, Rod Speed wrote:
> Paul <nospam@needed.invalid> wrote
>> Frank wrote
>
>>> It would seem that something is overheating perhaps?Is it likely to
>>> be   the transformer or the lamp?
>
> Much more likely to be the 'transformer' which isnt actually a transformer.

Maybe the driver circuit in bulb is shutting down. What some
manufactures have been including in their bulbs is temperature
protection IC. The LED current is reduced with a rising temperature and
possible shutting off if a threshold is exceeded.

https://youtu.be/5HTa2jVi_rc?t=386

In that video BigClive is comparing two different lamps - one of which
is over driving the LEDs

>
>> LED lamps and the SMPS in the base, really could use some airflow.
>
> None of my Philips Hues need that. Not even
> warm even when the room temp is 48C

LEDs and their electronics do not like getting hot irrespective of the
brand.

How hot a KED bulb gets often depends on the light fitting and many
downlight fittings that originally took halogens are unsuited for some
LED replacements.

>
>> This is why it is not recommended to place themin sealed globes,  such
>> as the globe in my kitchen.
>
> Works fine with the best bulbs.
>
>>
>> https://www.ledsmagazine.com/leds-ssl-design/thermal/article/16695318/accurate-thermal-simulation-enables-led-lighting-products-to-match-design-goals-magazine
>
>> While you could punch a hole in the top of a pot to allowthe  hot air
>> to escape, that might be a violation of a fire code.
>> I don't know the rules regarding modifications like that.
>
>> In any case, pots were designed for incandescents, and the ceramic
>> and metal in incandescent bulbs can take lots of heat. Relatively
>> speaking.
>
>> They make LEDs on silicon carbide substrates, to extend the temperature
>> range, but the problem is, some of the environments are just too
>> miserable
>> for such incremental improvements to help a lot. The article above
>> mentions
>> the electrolytic capacitor failing, and sometimes when the lamp dies
>> in only
>> three months, it's the cap that fried, not the LEDs. The capacitor
>> might only
>> be rated for 2000 hours at that temperature.
>
> But a failure of those wouldnt see the light cycle.
>
>> In the SMPS controller chip, it is easy to add an overtemperature
>> detector,
>> as substrate diodes are easy to do in silicon. It could be purposely
>> switching off,
>
> Not aware of any that do that and its unlikely
> to have just started doing that now, in winter.
>
>> or, the SMPS oscillator could havestopped switching for  some reason.
>
>> It you take the lamp out of the pot and operate it in open
>> air on your table, I bet it will run all day long without
>> winking out.
>
>> I have some lamps here, that are failing prematurely, and they *do*
>> have airflow. And that's how you know, how "cheerful" LEDs have become.

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

Brian Gaff wrote:

> You could try swapping them with ones that don't do it to see if the fault
> moves with the bulb. That should show what the issue is.

If they're mains LEDS there won't be any transformers ...

On 27/01/2024 11:03, Andy Burns wrote:
> Brian Gaff wrote:
>
>> You could try swapping them with ones that don't do it to see if the
>> fault
>> moves with the bulb. That should show what the issue is.
>
> If they're mains LEDS there won't be any transformers ...
>
Might be, in an SMPS. Not all are so crappy that they use capacitors for
current limiting
--
“It is hard to imagine a more stupid decision or more dangerous way of
making decisions than by putting those decisions in the hands of people
who pay no price for being wrong.”

Thomas Sowell

The Natural Philosopher wrote:

> On 27/01/2024 11:03, Andy Burns wrote:
>> Brian Gaff wrote:
>>
>>> You could try swapping them with ones that don't do it to see if the
>>> fault
>>> moves with the bulb. That should show what the issue is.
>>
>> If they're mains LEDS there won't be any transformers ...
>>
> Might be, in an SMPS. Not all are so crappy that they use capacitors for
> current limiting

But not user-accessible like 12V lighting trafo within the ceiling
void, likely to have to break the lamp open to see it ...

On Saturday 27 January 2024 at 12:06:58 UTC, Andy Burns wrote:
> The Natural Philosopher wrote:
>
> > On 27/01/2024 11:03, Andy Burns wrote:
> >> Brian Gaff wrote:
> >>
> >>> You could try swapping them with ones that don't do it to see if the
> >>> fault
> >>> moves with the bulb. That should show what the issue is.
> >>
> >> If they're mains LEDS there won't be any transformers ...
> >>
> > Might be, in an SMPS. Not all are so crappy that they use capacitors for
> > current limiting
> But not user-accessible like 12V lighting trafo within the ceiling
> void, likely to have to break the lamp open to see it ...

I had a bad batch of 12V led downlighters a few years ago which all started
cycling on and off just as described. It turned out that the bond wires
between the leds and the alumina substrate were not well bonded. As they
heated up the bond opened up and the led turned off. As they cooled
the connection was made again.
These were "chip on board" leds with a series/parallel matrix of leds on
a rectangular substrate, covered in phosphorescent gel.
They were from TLC who replaced them all several times over under warranty
until eventually they started working reliably.
John

On Sat, 27 Jan 2024 21:21:18 +1100, alan_m <junk@admac.myzen.co.uk> wrote:

> On 27/01/2024 00:38, Rod Speed wrote:
>> Paul <nospam@needed.invalid> wrote
>>> Frank wrote
>>
>>>> It would seem that something is overheating perhaps?Is it likely to
>>>> be the transformer or the lamp?
>> Much more likely to be the 'transformer' which isnt actually a
>> transformer.
>
> Maybe the driver circuit in bulb is shutting down. What some
> manufactures have been including in their bulbs is temperature
> protection IC. The LED current is reduced with a rising temperature and
> possible shutting off if a threshold is exceeded.
>
> https://youtu.be/5HTa2jVi_rc?t=386
>
> In that video BigClive is comparing two different lamps - one of which
> is over driving the LEDs
>
>>
>>> LED lamps and the SMPS in the base, really could use some airflow.

>> None of my Philips Hues need that. Not even
>> warm even when the room temp is 48C

> LEDs and their electronics do not like getting hot irrespective of the
> brand.

The Philips Hues don't get hot by design.

> How hot a KED bulb gets often depends on the light fitting and many
> downlight fittings that originally took halogens are unsuited for some
> LED replacements.

>>> This is why it is not recommended to place themin sealed globes, such
>>> as the globe in my kitchen.
>> Works fine with the best bulbs.
>>
>>>
>>> https://www.ledsmagazine.com/leds-ssl-design/thermal/article/16695318/accurate-thermal-simulation-enables-led-lighting-products-to-match-design-goals-magazine
>>
>>> While you could punch a hole in the top of a pot to allowthe hot air
>>> to escape, that might be a violation of a fire code.
>>> I don't know the rules regarding modifications like that.
>>
>>> In any case, pots were designed for incandescents, and the ceramic
>>> and metal in incandescent bulbs can take lots of heat. Relatively
>>> speaking.
>>
>>> They make LEDs on silicon carbide substrates, to extend the temperature
>>> range, but the problem is, some of the environments are just too
>>> miserable
>>> for such incremental improvements to help a lot. The article above
>>> mentions
>>> the electrolytic capacitor failing, and sometimes when the lamp dies
>>> in only
>>> three months, it's the cap that fried, not the LEDs. The capacitor
>>> might only
>>> be rated for 2000 hours at that temperature.
>> But a failure of those wouldnt see the light cycle.
>>
>>> In the SMPS controller chip, it is easy to add an overtemperature
>>> detector,
>>> as substrate diodes are easy to do in silicon. It could be purposely
>>> switching off,
>> Not aware of any that do that and its unlikely
>> to have just started doing that now, in winter.
>>
>>> or, the SMPS oscillator could havestopped switching for some reason.
>>
>>> It you take the lamp out of the pot and operate it in open
>>> air on your table, I bet it will run all day long without
>>> winking out.
>>
>>> I have some lamps here, that are failing prematurely, and they *do*
>>> have airflow. And that's how you know, how "cheerful" LEDs have become.

On Sun, 28 Jan 2024 03:41:41 +1100, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

<FLUSH the abnormal trolling senile cretin's latest trollshit unread>

--
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"Shit you're thick/pathetic excuse for a troll."
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On 1/27/2024 11:41 AM, Rod Speed wrote:
> On Sat, 27 Jan 2024 21:21:18 +1100, alan_m <junk@admac.myzen.co.uk> wrote:
>
>> On 27/01/2024 00:38, Rod Speed wrote:
>>> Paul <nospam@needed.invalid> wrote
>>>> Frank wrote
>>>
>>>>> It would seem that something is overheating perhaps?Is it likely to be   the transformer or the lamp?
>>>  Much more likely to be the 'transformer' which isnt actually a transformer.
>>
>> Maybe the driver circuit in bulb is shutting down. What some manufactures have been including in their bulbs is temperature protection IC. The LED current is reduced with a rising temperature and possible shutting off if a threshold is exceeded.
>>
>> https://youtu.be/5HTa2jVi_rc?t=386
>>
>> In that video BigClive is comparing two different lamps - one of which is over driving the LEDs
>>
>>>
>>>> LED lamps and the SMPS in the base, really could use some airflow.
>
>>>  None of my Philips Hues need that. Not even
>>> warm even when the room temp is 48C
>
>> LEDs and their electronics do not like getting hot irrespective of the  brand.
>
> The Philips Hues don't get hot by design.
>

Philips Hues

"A light which is off, consumes a standby wattage, the amount depends on the model, typically between 0.2 and 0.4 W
A light which is on, consumes the standby wattage + % of brightness * (wattage – standby wattage)
When a light is on, a brightness setting of 5% is the minimum used for the power consumption calculation
The above also applies to the Hue bridge, with an estimated 50% average continuous power consumption

This is a basic estimate, without knowing the exact power consumption (which depends on a combination
of factors like brightness, color, temperature, etc.) this is the closest estimate possible. Unfortunately,
the Hue bulbs do not measure their own power consumption.
"

"Smart LED bulbs consume very little power, especially when compared to incandescent bulbs.
An incandescent bulb uses 60 watts to emit 800 lumens. However, a Philips Hue smart bulb
delivers the same amount of light using just 9.5 watts." <===

I just went to the bulb cupboard, and pulled the cheesy Philips non-Hue.
This is the spec on the side of the box.

60W 800 lumens 8.8W 15,000 hours

So in fact, there is nothing magical about a Hue.

If I need a 40W lamp, I screw in a 40W lamp.
If i need a 60W lamp, I screw in a 60W lamp.
If I need a 100W lamp, I screw in a 100W lamp.

All of the bulbs in the cupboard use SMPS. There
are no low power capacitive-dropper bulbs, no Dubai bulbs.
And the laws of physics have not been repealed. The bulbs
all use electricity in proportion to the light output.
There are no Sparkle Ponies in the room at the moment.

If you set your Hue to 100%, because you need the light to see,
then your bulb uses 9.5W (according to the promo prompt on the Philips page)
and mine uses 8.8W. Waste heat comes from the package, the SMPS
gets warm inside due to the modern bulbs having less
heat dissipating surface area.

And it's not just the "15,000 hour" bullshit rating of the bulbs.
The bulbs so far, are blowing out a lot faster than the 15,000
hour rating implies. Which is... not good.

The bulbs now have a "switching cycle" rating, but even taking
that into account, they're still blowing out too soon. These
are not bulbs that are failing because "the LED output has dropped
to 70% of the initial brilliance". These are things like SMPS failures.
The bulbs are never in globes, the bulbs have convection air to use.

The best SMPS I know of, were made at work, with a computed reliability
of 100 FITS. That's ten million hours (5x a hard drive). These are
smaller devices with not very impressive power output. But they have
the best FITS numbers I know of. Because someone asked the engineers
in the power supply division to "make a good FITS product".

Larger power supplies weigh in at 3000 FITS, by comparison. Thirty times
less reliable.

If we were to measure the field reliability of light bulb FITS,
what would we find ? We would find "utter shite". That is what we
would find. So don't be telling me how wonderful light bulbs
are. They're little better than incandescent now, once they
removed the heatsinks.

Back when I was testing CFLs, and the SMPS in the base of the
CFL would fail and make a stink, it was the same. Unreliable.
Failing before their time. When the last CFL made a stain
on the ceiling, that was the last straw. I still have CFLs
I won't use, sitting in cupboard, because I know how
they will leave this world, with a stink and a stain.

At least the LEDs blow, without a chemical halo. I guess
that is progress.

Paul

On 1/27/2024 5:06 AM, Brian Gaff wrote:
> If an Led power supply gets hot its hardly being very efficient is it? Are
> these all the same maker etc? I remember also aperson telling me that the
> colour temp of some supposedly the same leds can be different, indeed
> variations exist inside one light. I've never chopped one to bits to see
> what is there, but you can bet they have cut out all unrequited parts and
> used the cheapest chips and Leeds they can get.
> Brian
>

The LEDs are blue emitters, with a yellowish-tinted phosphor
coating on top of the blue LED. This converts the light
into some shade of white.

Some bulbs, have tossed in a couple red LEDs (without phosphors),
to adjust the spectrum a bit.

You can spend more money on the phosphor composition (precious materials)
to make more corrections to the spectrum.

The higher the colour temperature (like 9000K for light humans don't want),
there is a thinner phosphor coating on those, and the "base lumens" is
greater. The phosphor wastes some of the energy, so you get fewer lumens
with a thick phosphor coat, but a more pleasing colour. The 9000K lamps
might work on a bicycle, as an example of an application. You're not
reading a book when riding a bicycle :-)

Philips made some remote-phosphor lamps. The room I'm sitting in, is lit
by one of those. The LEDs in the lamp inside are blue (if you smashed the
lamp envelope, you would be seeing blue). The plastic shell on the lamp,
has the phosphor coating. This is to avoid the "phosphor smothering" problem.
But remote-phosphor lamps have come and gone. They don't make those any more.

Paul

Paul <nospam@needed.invalid> wrote
> Rod Speed wrote
>> alan_m <junk@admac.myzen.co.uk> wrote
>>> Rod Speed wrote
>>>> Paul <nospam@needed.invalid> wrote
>>>>> Frank wrote

>>>>>> It would seem that something is overheating perhaps?
>>>>>> Is it likely to be the transformer or the lamp?

>>>> Much more likely to be the 'transformer'which isnt actually a
>>>> transformer.

>>> Maybe the driver circuit in bulb is shutting down. What some
>>> manufactures have been including in their bulbs is temperature
>>> protection IC. The LED current is reduced with a rising temperature
>>> and possible shutting off if a threshold is exceeded.

>>> https://youtu.be/5HTa2jVi_rc?t=386

>>> In that video BigClive is comparing two differentlamps - one of which
>>> is over driving the LEDs

>>>>> LED lamps and the SMPS in the base, really could use some airflow.

>>>> None of my Philips Hues need that. Not even
>>>> warm even when the room temp is 48C

>>> LEDs and their electronics do not likegetting hot irrespective of
>>> the brand.

>> The Philips Hues don't get hot by design.

> Philips Hues

> "A light which is off, consumes a standby wattage, the amountdepends
> on the model, typically between 0.2 and 0.4 W

Irrelevant to whether it gets hot.

> A light which is on, consumes the standby wattage +% of brightness
> * (wattage – standby wattage)

Duh.

> When a light is on, a brightness setting of 5% is theminimum used
> for the power consumption calculation

Irrelevant to whether it gets hot.

> The above also applies to the Hue bridge, with an estimated 50%
> average continuous power consumption

Irrelevant to whether the BULB gets hot.

> This is a basic estimate, without knowing the exact power
> consumption (which depends on a combination
> of factors like brightness, color, temperature, etc.) this is the
> closest estimate possible. Unfortunately,
> the Hue bulbs do not measure their own power consumption.
> "

So what was the point in quoting this ?

> "Smart LED bulbs consume very little power, especiallywhen compared
> to incandescent bulbs.
> An incandescent bulb uses 60 watts to emit 800 lumens. However, a
> Philips Hue smart bulb
> delivers the same amount of light using just 9.5 watts." <==
Which explains why it doesnt get hot given the size if the bulbs.

> I just went to the bulb cupboard, and pulled the cheesy Philips non-Hue.
> This is the spec on the side of the box.

> 60W 800 lumens 8.8W 15,000 hours

> So in fact, there is nothing magical about a Hue.

No one said there was. What was being
discussed was whether they GET HOT.

Clearly they don't if they only consume 9W and are
big enough so that that doesnt run anything hot.

> If I need a 40W lamp, I screw in a 40W lamp.
> If i need a 60W lamp, I screw in a 60W lamp.
> If I need a 100W lamp, I screw in a 100W lamp.

You quite sure you aint one of those rocket scientist fellas ?

> All of the bulbs in the cupboard use SMPS. There
> are no low power capacitive-dropper bulbs, no Dubai bulbs.
> And the laws of physics have not been repealed. The bulbs
> all use electricity in proportion to the light output.

You quite sure you aint one of those rocket scientist fellas ?

> There are no Sparkle Ponies in the room at the moment.

> If you set your Hue to 100%, because you need the light to see,
> then your bulb uses 9.5W (according to the promo prompt on the Philips
> page)
> and mine uses 8.8W. Waste heat comes from the package,

You quite sure you aint one of those rocket scientist fellas ?

> the SMPS gets warm inside due to the modernbulbs having less heat
> dissipating surface area.

That's not true of the E27 Philips Hue bulbs.

> And it's not just the "15,000 hour" bullshit rating of the bulbs.
> The bulbs so far, are blowing out a lot faster than the 15,000
> hour rating implies. Which is... not good.

I haven't lost even a single one and most of them are on for
hours daily given that I do multiphase sleeping which means
that I spend quite a bit of time up and about at night.

> The bulbs now have a "switching cycle" rating, but even taking
> that into account, they're still blowing out too soon.

Yours arent HUEs.

> These are not bulbs that are failing because "the LED output has dropped
> to 70% of the initial brilliance". These are things like SMPS failures..
> The bulbs are never in globes, the bulbs have convection air to use.

Same with mine.

<reams of irrelevancy to whether Philips Hues GET HOT flushed where it
belongs>

> If we were to measure the field reliability of light bulb FITS,
> what would we find ? We would find "utter shite". That is what we
> would find. So don't be telling me how wonderful light bulbs
> are. They're little better than incandescent now, once they
> removed the heatsinks.

My Philips Hues are MUCH more reliable than incandescents ever where.

On Friday 26 January 2024 at 23:31:01 UTC, Frank wrote:
> We have several mains voltage LED downlighters and a couple have taken
> to turning off after they've been on for a while and then turning back
> on after a couple of minutes.
>
> It would seem that something is overheating perhaps?

probably

> Is it likely to be
> the transformer or the lamp?

Yes, it's a failure pattern of both LEDs & their ballasts so who knows

On Sun, 28 Jan 2024 06:57:02 +1100, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

<FLUSH the abnormal trolling senile cretin's latest trollshit unread>

--
Xeno to senile Rodent:
"You're a sad old man Rod, truly sad."
MID: <id04c3F50peU1@mid.individual.net>

On 27/01/2024 18:29, Paul wrote:
> I still have CFLs
> I won't use, sitting in cupboard, because I know how

Mine all got tired and dim.

Ive got a boxful of them in case there is ever a need for them But they
are in general pants compared with LEDs

And LEDs are failing after 1-2 years too. And the dimmable ones flicker
on the dimmers.

But the technology seems to be improving...

--
“it should be clear by now to everyone that activist environmentalism
(or environmental activism) is becoming a general ideology about humans,
about their freedom, about the relationship between the individual and
the state, and about the manipulation of people under the guise of a
'noble' idea. It is not an honest pursuit of 'sustainable development,'
a matter of elementary environmental protection, or a search for
rational mechanisms designed to achieve a healthy environment. Yet
things do occur that make you shake your head and remind yourself that
you live neither in Joseph Stalin’s Communist era, nor in the Orwellian
utopia of 1984.”

Vaclav Klaus