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SOT: Do LED bulbs interfere with DAB radio?
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Scott
Dec 26, 2016, 8:29:25 AM12/26/16
to
I installed LED spotlights in the kitchen and when they are all on the
DAB radio stops working. I am wondering if this is due to:
1. A general problem with LED lighting (in which case is it fit for
purpose for domestic use?)
2. A single faulty bulb
3. A particular issue with 12 Volt bulbs
I should explain this is a somewhat unusual installation. The lights
are powered by torroidal transformers (for which I am assured there is
no minimum load). The transformers are a long way from the radio and
have never previously caused difficulties, so I am convinced the
problems lie with the bulbs themselves.
A quick search suggests that the problem could be Electromagnetic
Compatibility (EMC) or lack of it.
Any ideas among the experts?
DAB radio stops working. I am wondering if this is due to:
1. A general problem with LED lighting (in which case is it fit for
purpose for domestic use?)
2. A single faulty bulb
3. A particular issue with 12 Volt bulbs
I should explain this is a somewhat unusual installation. The lights
are powered by torroidal transformers (for which I am assured there is
no minimum load). The transformers are a long way from the radio and
have never previously caused difficulties, so I am convinced the
problems lie with the bulbs themselves.
A quick search suggests that the problem could be Electromagnetic
Compatibility (EMC) or lack of it.
Any ideas among the experts?
Woody
Dec 26, 2016, 8:59:51 AM12/26/16
to
"Scott" <newsg...@gefion.myzen.co.uk> wrote in message
news:m7626c9n1ipi9nt21...@4ax.com...
signal on DAB? There is usually somewhere in the menu system a signal
strength indication - does this indication vary between lights on and
lights off? Does the indication vary with the number of lamps lit?
What is the nature of the DAB problem - does it go to bubbling mud or
does the radio just mute?
That's a start.
--
Woody
harrogate3 at ntlworld dot com
Scott
Dec 26, 2016, 9:39:05 AM12/26/16
to
On Mon, 26 Dec 2016 13:59:55 -0000, "Woody" <harro...@ntlworld.com>
wrote:
>
>"Scott" <newsg...@gefion.myzen.co.uk> wrote in message
>news:m7626c9n1ipi9nt21...@4ax.com...
>>I installed LED spotlights in the kitchen and when they are all on
>>the
>> DAB radio stops working. I am wondering if this is due to:
>>
>> 1. A general problem with LED lighting (in which case is it fit for
>> purpose for domestic use?)
>> 2. A single faulty bulb
>> 3. A particular issue with 12 Volt bulbs
>>
>> I should explain this is a somewhat unusual installation. The
>> lights
>> are powered by torroidal transformers (for which I am assured there
>> is
>> no minimum load). The transformers are a long way from the radio
>> and
>> have never previously caused difficulties, so I am convinced the
>> problems lie with the bulbs themselves.
>>
>> A quick search suggests that the problem could be Electromagnetic
>> Compatibility (EMC) or lack of it.
>>
>> Any ideas among the experts?
>
>Questions in advance of the expert start: do you normally get a good
>signal on DAB? There is usually somewhere in the menu system a signal
>strength indication
Yes - signal error between varies 3 and 5. I'm in a top floor flat so
DAB reception is not normally a problem.
closest cause the biggest problem.
>That's a start.
And thanks for that.
They are MR16 lamps (14 in total). I'm also going to write to the
supplier to see if they are EMC compliant. No mention of this on the
box (however, as the wattage and halogen equivalence are both wrong on
the box due to a 'printing error' I am not very confident about any of
the information I am being given..
wrote:
>
>"Scott" <newsg...@gefion.myzen.co.uk> wrote in message
>news:m7626c9n1ipi9nt21...@4ax.com...
>>I installed LED spotlights in the kitchen and when they are all on
>>the
>> DAB radio stops working. I am wondering if this is due to:
>>
>> 1. A general problem with LED lighting (in which case is it fit for
>> purpose for domestic use?)
>> 2. A single faulty bulb
>> 3. A particular issue with 12 Volt bulbs
>>
>> I should explain this is a somewhat unusual installation. The
>> lights
>> are powered by torroidal transformers (for which I am assured there
>> is
>> no minimum load). The transformers are a long way from the radio
>> and
>> have never previously caused difficulties, so I am convinced the
>> problems lie with the bulbs themselves.
>>
>> A quick search suggests that the problem could be Electromagnetic
>> Compatibility (EMC) or lack of it.
>>
>> Any ideas among the experts?
>
>Questions in advance of the expert start: do you normally get a good
>signal on DAB? There is usually somewhere in the menu system a signal
>strength indication
DAB reception is not normally a problem.
>- does this indication vary between lights on and
>lights off?
Yes - with all the lights on it goes to 'No audio'.
>lights off?
>Does the indication vary with the number of lamps lit?
Yes.
>What is the nature of the DAB problem - does it go to bubbling mud or
>does the radio just mute?
It deteriorates to bubbling mud as the lights are turned on. The ones
>does the radio just mute?
closest cause the biggest problem.
>That's a start.
And thanks for that.
They are MR16 lamps (14 in total). I'm also going to write to the
supplier to see if they are EMC compliant. No mention of this on the
box (however, as the wattage and halogen equivalence are both wrong on
the box due to a 'printing error' I am not very confident about any of
the information I am being given..
charles
Dec 26, 2016, 9:50:18 AM12/26/16
to
In article <j5b26c5gkega46km3...@4ax.com>,
Martin <m...@address.invalid> wrote:
> Our street is lit with LED lamps, but no problems with DAB radio.
but they are a bit further awy from your radio than his kitchen lights are
from his.
--
from KT24 in Surrey, England
Martin <m...@address.invalid> wrote:
but they are a bit further awy from your radio than his kitchen lights are
from his.
--
from KT24 in Surrey, England
David Woolley
Dec 26, 2016, 9:53:08 AM12/26/16
to
On 26/12/16 14:39, Scott wrote:
> I'm also going to write to the
> supplier to see if they are EMC compliant. No mention of this on the
> box
The E symbol on the box is the claim of compliance. If they do not have
> I'm also going to write to the
> supplier to see if they are EMC compliant. No mention of this on the
> box
that, they should not have been on sale.
However, as the other questions are hinting at, EMC compliance basically
only means that they generate a commercially acceptable level of noise,
not that that noise is way below the natural background. If your
reception is marginal, they will push you over the limit.
Incidentally, it is not the LEDs that cause the RFI, but the switch mode
power supply that generates a constant current for them. If you want to
control RFI, you should install LED's with no built in power supply and
use a, well suppressed, external, constant current power supply. They
will no longer be standard 12V bulbs, but rather, typically 350mA or
700mA devices, and you will typically series connect them, rather than
parallel
It is possible that your ELV wiring has not been done well. To minimise
radiation, you should use twisted pair, of a suitable current rating, or
at least ensure that both wires of the pair are together.
Scott
Dec 26, 2016, 10:15:59 AM12/26/16
to
On Mon, 26 Dec 2016 14:53:01 +0000, David Woolley
<da...@ex.djwhome.demon.invalid> wrote:
>On 26/12/16 14:39, Scott wrote:
>> I'm also going to write to the
>> supplier to see if they are EMC compliant. No mention of this on the
>> box
>
>The E symbol on the box is the claim of compliance. If they do not have
>that, they should not have been on sale.
Do you mean 'CE'? This is marked on the box.
<da...@ex.djwhome.demon.invalid> wrote:
>On 26/12/16 14:39, Scott wrote:
>> I'm also going to write to the
>> supplier to see if they are EMC compliant. No mention of this on the
>> box
>
>The E symbol on the box is the claim of compliance. If they do not have
>that, they should not have been on sale.
>
>However, as the other questions are hinting at, EMC compliance basically
>only means that they generate a commercially acceptable level of noise,
>not that that noise is way below the natural background. If your
>reception is marginal, they will push you over the limit.
I think the reception is pretty good - usually in the high 90s. I
>However, as the other questions are hinting at, EMC compliance basically
>only means that they generate a commercially acceptable level of noise,
>not that that noise is way below the natural background. If your
>reception is marginal, they will push you over the limit.
live in a top floor flat. A new fill-in transmitter has recently been
opened.
>
>Incidentally, it is not the LEDs that cause the RFI, but the switch mode
>power supply that generates a constant current for them. If you want to
>control RFI, you should install LED's with no built in power supply and
>use a, well suppressed, external, constant current power supply. They
>will no longer be standard 12V bulbs, but rather, typically 350mA or
>700mA devices, and you will typically series connect them, rather than
>parallel
As I mentioned, these are run from three toroidal transormers. I
>Incidentally, it is not the LEDs that cause the RFI, but the switch mode
>power supply that generates a constant current for them. If you want to
>control RFI, you should install LED's with no built in power supply and
>use a, well suppressed, external, constant current power supply. They
>will no longer be standard 12V bulbs, but rather, typically 350mA or
>700mA devices, and you will typically series connect them, rather than
>parallel
appreciate this means they receive AC supply but do they still have
built-in switched mode power supply? I see they are AC or DC so could
I fit a rectifier to the transformer output and would running on DC
make a difference?
>
>It is possible that your ELV wiring has not been done well. To minimise
>radiation, you should use twisted pair, of a suitable current rating, or
>at least ensure that both wires of the pair are together.
>
It is very likely as the wiring was done several years ago for halogen
>It is possible that your ELV wiring has not been done well. To minimise
>radiation, you should use twisted pair, of a suitable current rating, or
>at least ensure that both wires of the pair are together.
>
lights with no thought of twisted pairs. They are certainly together
as it is two core flex.
R. Mark Clayton
Dec 26, 2016, 10:24:30 AM12/26/16
to
The problem could be radio interference or more likely 100 - 200Khz chopped square wave leaking back down through the mains. Try one of those clip on chokes on the light supply as close the PSU as you can get. Also try plugging either into an extension lead from another room.
Scott
Dec 26, 2016, 10:30:08 AM12/26/16
to
toroidal transformer connected to the lighting circuit? Could I
filter the transformer output instead?
Scott
Dec 26, 2016, 10:40:22 AM12/26/16
to
On Mon, 26 Dec 2016 16:40:23 +0100, Martin <m...@address.invalid> wrote:
>On Mon, 26 Dec 2016 14:49:13 +0000 (GMT), charles <cha...@candehope.me.uk>
>wrote:
>They are also far more powerful. What effect does his LED TV have on his DAB
>radio?
None, as they are at opposite ends of the flat.
>On Mon, 26 Dec 2016 14:49:13 +0000 (GMT), charles <cha...@candehope.me.uk>
>wrote:
>radio?
None, as they are at opposite ends of the flat.
David Woolley
Dec 26, 2016, 10:41:56 AM12/26/16
to
On 26/12/16 15:15, Scott wrote:
> they receive AC supply but do they still have
> built-in switched mode power supply?
Yes. LEDs run on constant current not constant voltage. Although you
> they receive AC supply but do they still have
> built-in switched mode power supply?
can run them with a series dropper resistor, that is not very efficient.
> I see they are AC or DC so could
> I fit a rectifier to the transformer output and would running on DC
> make a difference?
converter, anyway.
PS I did mean CE.
David Woolley
Dec 26, 2016, 10:46:02 AM12/26/16
to
On 26/12/16 15:30, Scott wrote:
> Would this still apply where the LEDs receive their power via a
> toroidal transformer connected to the lighting circuit? Could I
> filter the transformer output instead?
Ideally you want the filter as close as possible to the switch mode
> Would this still apply where the LEDs receive their power via a
> toroidal transformer connected to the lighting circuit? Could I
> filter the transformer output instead?
power supply, i.e. close to the LEDs themselves.
In this context what you call the output of the transformer is actually
the input for the interfering signal, but filtering either side will
help as long as interference is mains born, but if it is being radiated
by the extra low voltage wiring, you need to filter it on the LED side
of that, not the transformer side.
David Woolley
Dec 26, 2016, 10:49:53 AM12/26/16
to
On 26/12/16 15:40, Martin wrote:
> They are also far more powerful. What effect does his LED TV have on his DAB
> radio?
> -
> They are also far more powerful. What effect does his LED TV have on his DAB
> radio?
It is not the LEDs that cause the interference, but the contstant
current power supply that feeds them. The power supply in the TV may
well be part of the general power supply complex for the TV, and
therefore it may not be possible to distinguish between interference
from the supplies that run the receiver and those that run the LEDs.
I think you can safely assume that each LED doesn't have its own power
supply. Doing that on domestic lighting is done for backwards
compatibility, so that people can replace filament bulbs with LED ones
without having to redo the wiring.
Scott
Dec 26, 2016, 10:50:45 AM12/26/16
to
different radio to see if the radio is to blame.)
R. Mark Clayton
Dec 26, 2016, 11:05:07 AM12/26/16
to
R. Mark Clayton
Dec 26, 2016, 11:07:15 AM12/26/16
to
> (As an afterthought I'll also try a
> different radio to see if the radio is to blame.)
Scott
Dec 26, 2016, 11:10:15 AM12/26/16
to
On Mon, 26 Dec 2016 08:05:06 -0800 (PST), "R. Mark Clayton"
Not mains, 12 Volts. Will the same chokes work?
R. Mark Clayton
Dec 26, 2016, 11:20:23 AM12/26/16
to
Woody
Dec 26, 2016, 12:02:37 PM12/26/16
to
As a point of interest, what make/model is the radio, and does it have
an internal PSU or a wall-wart? If it is the latter it will likely
have a ferrite on the cable just before the d.c. connector plug at the
radio end.
One thing to try is replacing one of the LED lamps with a halogen. If
the PSU is electronic it may be that it needs a minimum load and with
the use of LEDs their total load may be below that minimum. A single
halogen (1) should increase the load above the minimum and (2) the
halogen lamp itself <may> dampen any 'dirt' generated by the other
lamps.
The OP does not say if there is a dimmer on the circuit?
I did ask earlier if the radio was indicating a change in signal when
the lamps are on. I should explain a little more I think. Most DAB
radios somewhere in the menu have an indication of signal strength and
some also of signal quality. With DAB it is much more the quality that
matters. Something was said about 3 and 5 earlier - but 3 and 5 out of
how many - 10? 50? 100? It is all relative. Writing down the various
combinations of strength and quality under different lighting
circumstances including the mod suggested above might give some
further pointers. The fact that a new transmitter has recently opened
does not necessarily mean it is being used as DAB is a single
frequency network so <any> transmitter or combination of local
transmitters could be supplying the signal.
Finally, something that has just occurred to me. It sounds as though
there are different groupings of lights independently switchable. Does
a single PSU feed everything or is there one PSU for each switched
circuit? If it is the former then the 12V will be being handled by the
switches which means that single cables that carry the power to the
lights will be going to the switches and thus not being an
electrically balanced pair (as in twin flex or whatever carrying +ve
and -ve) they will radiate if there is any interference on them.
Substituting a halogen lamp will require one on each supply if there
is more than one, or if only one PSU then the halogen should be fitted
such that it will always be on, i.e. the first one on entering the
room?
an internal PSU or a wall-wart? If it is the latter it will likely
have a ferrite on the cable just before the d.c. connector plug at the
radio end.
One thing to try is replacing one of the LED lamps with a halogen. If
the PSU is electronic it may be that it needs a minimum load and with
the use of LEDs their total load may be below that minimum. A single
halogen (1) should increase the load above the minimum and (2) the
halogen lamp itself <may> dampen any 'dirt' generated by the other
lamps.
The OP does not say if there is a dimmer on the circuit?
I did ask earlier if the radio was indicating a change in signal when
the lamps are on. I should explain a little more I think. Most DAB
radios somewhere in the menu have an indication of signal strength and
some also of signal quality. With DAB it is much more the quality that
matters. Something was said about 3 and 5 earlier - but 3 and 5 out of
how many - 10? 50? 100? It is all relative. Writing down the various
combinations of strength and quality under different lighting
circumstances including the mod suggested above might give some
further pointers. The fact that a new transmitter has recently opened
does not necessarily mean it is being used as DAB is a single
frequency network so <any> transmitter or combination of local
transmitters could be supplying the signal.
Finally, something that has just occurred to me. It sounds as though
there are different groupings of lights independently switchable. Does
a single PSU feed everything or is there one PSU for each switched
circuit? If it is the former then the 12V will be being handled by the
switches which means that single cables that carry the power to the
lights will be going to the switches and thus not being an
electrically balanced pair (as in twin flex or whatever carrying +ve
and -ve) they will radiate if there is any interference on them.
Substituting a halogen lamp will require one on each supply if there
is more than one, or if only one PSU then the halogen should be fitted
such that it will always be on, i.e. the first one on entering the
room?
Jim Lesurf
Dec 26, 2016, 12:17:24 PM12/26/16
to
In article <v5g26c5jmhl00kd1p...@4ax.com>, Scott
trick is to get them close to the part of the system that is doing the
switching. But there is no certainty that will totally fix the problem. If
they are badly made, they could be *very* badly made.
Note that if you can't fix the problem without a lot of bother it may make
more sense to return them as faulty and/or not meeting the regulations wrt
interference. Your contract is with whoever you bought them from. The
requirements for manufacturers to adhere to the regulations is mandated
specifically so that buyers like yourself need not have the bother of
fixing such flaws. If the seller refuses your next step would be Trading
Standards or the CAB.
Can you give details of the model/make/etc? Might help others to advise.
And warn potential buyers about something to avoid.
Jim
--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scots_Guide/intro/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html
<newsg...@gefion.myzen.co.uk> wrote:
> >On reflection both - those clip on ferrite mains chokes are cheap.
> Not mains, 12 Volts. Will the same chokes work?
Difficult to tell without knowing a lot more, or simply trying them. The
> >On reflection both - those clip on ferrite mains chokes are cheap.
> Not mains, 12 Volts. Will the same chokes work?
trick is to get them close to the part of the system that is doing the
switching. But there is no certainty that will totally fix the problem. If
they are badly made, they could be *very* badly made.
Note that if you can't fix the problem without a lot of bother it may make
more sense to return them as faulty and/or not meeting the regulations wrt
interference. Your contract is with whoever you bought them from. The
requirements for manufacturers to adhere to the regulations is mandated
specifically so that buyers like yourself need not have the bother of
fixing such flaws. If the seller refuses your next step would be Trading
Standards or the CAB.
Can you give details of the model/make/etc? Might help others to advise.
And warn potential buyers about something to avoid.
Jim
--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scots_Guide/intro/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html
Woody
Dec 26, 2016, 12:27:27 PM12/26/16
to
"Jim Lesurf" <no...@audiomisc.co.uk> wrote in message
news:55f49cd...@audiomisc.co.uk...
Export.........................
David Woolley
Dec 26, 2016, 1:51:01 PM12/26/16
to
On 26/12/16 17:02, Woody wrote:
> Finally, something that has just occurred to me. It sounds as though
> there are different groupings of lights independently switchable. Does
> a single PSU feed everything or is there one PSU for each switched
> circuit? If it is the former then the 12V will be being handled by the
I believe he is using MR16 bulbs. These take an AC, not DC feed, so he
> Finally, something that has just occurred to me. It sounds as though
> there are different groupings of lights independently switchable. Does
> a single PSU feed everything or is there one PSU for each switched
> circuit? If it is the former then the 12V will be being handled by the
is using a simple, linear, transformer. Each bulb has a switching power
supply inside it.
Whilst you can get LEDs without the power supply and use an external,
constant current, DC one, they seem to be more of professional product,
with consumer ones being for retrofitting on 240 or 12V AC supplies.
Linear transformers have no minimum load, but such circuits would have
been designed for halogen type incandescent bulbs.
Woody
Dec 26, 2016, 4:36:07 PM12/26/16
to
"David Woolley" <da...@ex.djwhome.demon.invalid> wrote in message
news:o3ronq$pgt$1...@dont-email.me...
output voltage would vary quite considerably with load which is <not>
a good idea. It could be an electronic transformer giving a.c.
output - they do exist - which would give a regulated source - and
more and more interference?
Scott
Dec 26, 2016, 5:28:00 PM12/26/16
to
On Mon, 26 Dec 2016 08:20:22 -0800 (PST), "R. Mark Clayton"
There was no problem when the transformer was running halogen bulbs.
Can the interference be passed backwards through the transformer into
the mains? As the lights nearest the radio cause the greatest problem
and all the transformers are together - and connected to the lighting
circuit of course - this seems unlikely.
Can the interference be passed backwards through the transformer into
the mains? As the lights nearest the radio cause the greatest problem
and all the transformers are together - and connected to the lighting
circuit of course - this seems unlikely.
Scott
Dec 26, 2016, 5:48:03 PM12/26/16
to
On Mon, 26 Dec 2016 17:02:46 -0000, "Woody" <harro...@ntlworld.com>
wrote:
>As a point of interest, what make/model is the radio, and does it have
>an internal PSU or a wall-wart? If it is the latter it will likely
>have a ferrite on the cable just before the d.c. connector plug at the
>radio end.
Roberts Stream 83i. 'Wall-wart' on the floor. Ferrite as you
suggest.
stated is toroidal like this:
http://www.mr-resistor.co.uk/item.aspx?i=7576
MInimum wattage on this one is 10 Watts so there is no question of
four of five spotlights being below this figure.
corresponds to quality.
> It is all relative. Writing down the various
>combinations of strength and quality under different lighting
>circumstances including the mod suggested above might give some
>further pointers.
It seems clear that there is correlation. I turned on the lights and
the radio signal collapsed. I turned off the lights and the radio
recovered.
>The fact that a new transmitter has recently opened
>does not necessarily mean it is being used as DAB is a single
>frequency network so <any> transmitter or combination of local
>transmitters could be supplying the signal.
Assuming this is the correct one, it includes BBC National:
http://tx.mb21.co.uk/mapsys/google/hitlist.php#map
gang switch as you enter the room.
wrote:
>As a point of interest, what make/model is the radio, and does it have
>an internal PSU or a wall-wart? If it is the latter it will likely
>have a ferrite on the cable just before the d.c. connector plug at the
>radio end.
suggest.
>
>One thing to try is replacing one of the LED lamps with a halogen. If
>the PSU is electronic it may be that it needs a minimum load and with
>the use of LEDs their total load may be below that minimum. A single
>halogen (1) should increase the load above the minimum and (2) the
>halogen lamp itself <may> dampen any 'dirt' generated by the other
>lamps.
Not sure what you mean by PSU in this context. The transformer as I
>One thing to try is replacing one of the LED lamps with a halogen. If
>the PSU is electronic it may be that it needs a minimum load and with
>the use of LEDs their total load may be below that minimum. A single
>halogen (1) should increase the load above the minimum and (2) the
>halogen lamp itself <may> dampen any 'dirt' generated by the other
>lamps.
stated is toroidal like this:
http://www.mr-resistor.co.uk/item.aspx?i=7576
MInimum wattage on this one is 10 Watts so there is no question of
four of five spotlights being below this figure.
>
>The OP does not say if there is a dimmer on the circuit?
There isn't.
>The OP does not say if there is a dimmer on the circuit?
>
>I did ask earlier if the radio was indicating a change in signal when
>the lamps are on. I should explain a little more I think. Most DAB
>radios somewhere in the menu have an indication of signal strength and
>some also of signal quality. With DAB it is much more the quality that
>matters. Something was said about 3 and 5 earlier - but 3 and 5 out of
>how many - 10? 50? 100?
The radio does not state out of how many. I assumed 'signal error'
>I did ask earlier if the radio was indicating a change in signal when
>the lamps are on. I should explain a little more I think. Most DAB
>radios somewhere in the menu have an indication of signal strength and
>some also of signal quality. With DAB it is much more the quality that
>matters. Something was said about 3 and 5 earlier - but 3 and 5 out of
>how many - 10? 50? 100?
corresponds to quality.
> It is all relative. Writing down the various
>combinations of strength and quality under different lighting
>circumstances including the mod suggested above might give some
>further pointers.
the radio signal collapsed. I turned off the lights and the radio
recovered.
>The fact that a new transmitter has recently opened
>does not necessarily mean it is being used as DAB is a single
>frequency network so <any> transmitter or combination of local
>transmitters could be supplying the signal.
http://tx.mb21.co.uk/mapsys/google/hitlist.php#map
>
>Finally, something that has just occurred to me. It sounds as though
>there are different groupings of lights independently switchable. Does
>a single PSU feed everything or is there one PSU for each switched
>circuit? If it is the former then the 12V will be being handled by the
>switches which means that single cables that carry the power to the
>lights will be going to the switches and thus not being an
>electrically balanced pair (as in twin flex or whatever carrying +ve
>and -ve) they will radiate if there is any interference on them.
>Substituting a halogen lamp will require one on each supply if there
>is more than one, or if only one PSU then the halogen should be fitted
>such that it will always be on, i.e. the first one on entering the
>room?
Three lighting groups each powered by a toroidal transformer. Three
>Finally, something that has just occurred to me. It sounds as though
>there are different groupings of lights independently switchable. Does
>a single PSU feed everything or is there one PSU for each switched
>circuit? If it is the former then the 12V will be being handled by the
>switches which means that single cables that carry the power to the
>lights will be going to the switches and thus not being an
>electrically balanced pair (as in twin flex or whatever carrying +ve
>and -ve) they will radiate if there is any interference on them.
>Substituting a halogen lamp will require one on each supply if there
>is more than one, or if only one PSU then the halogen should be fitted
>such that it will always be on, i.e. the first one on entering the
>room?
gang switch as you enter the room.
Jeff Layman
Dec 27, 2016, 3:45:54 AM12/27/16
to
one way to see if the interference is mains-borne or not.
--
Jeff
Jeff Layman
Dec 27, 2016, 3:50:13 AM12/27/16
to
"As I mentioned, these are run from three toroidal transformers. I
appreciate this means they receive AC supply but do they still have
built-in switched mode power supply? I see they are AC or DC so could
I fit a rectifier to the transformer output and would running on DC
make a difference? "
If they are AC or DC, wouldn't they have to have a SMPS unless there was
make a difference? "
an instruction to try the bulbs the other way round if they don't work
at first on a DC supply?
--
Jeff
David Woolley
Dec 27, 2016, 4:40:33 AM12/27/16
to
On 27/12/16 08:50, Jeff Layman wrote:
> If they are AC or DC, wouldn't they have to have a SMPS unless there was
I thought that is what I said!
> If they are AC or DC, wouldn't they have to have a SMPS unless there was
Medium quality domestic LED bulbs (and modern CFLs) have a constant
current SMPS incorporated in the bulb itself, and this is what causes
the interference.
Very cheap ones, particularly the corn cob type, which may not actually
be safe, use a capacitive divider, so generate much less RFI but may not
actually be legal. They normally run direct from the mains.
> an instruction to try the bulbs the other way round if they don't work
> at first on a DC supply?
SMPS, as half wave rectifying would not be acceptable these days because
of the harmonics it would put onto the mains. As such, if you wanted to
power them from DC, you should use a full wave rectifier, but this is
not going to help with the RFI. The only way of completely eliminating
the LED units as an RFI source is to use professional LEDs which use a
separate constant current driver (or use the very cheap, market store
type, with a capacitative dropper.
David Woolley
Dec 27, 2016, 4:45:43 AM12/27/16
to
On 27/12/16 08:45, Jeff Layman wrote:
> Is it possible to run your DAB radio from batteries? If so, it might be
> one way to see if the interference is mains-borne or not.
Even if it is not mains born, the 12V wiring is almost certainly acting
> Is it possible to run your DAB radio from batteries? If so, it might be
> one way to see if the interference is mains-borne or not.
as an antenna.
In fact, the toroidal transformer may well be quite effective at
blocking common noise from reaching the mains, which is all that the
clip on filters will do. A rather more expensive filter is needed to
keep the bulk of the noise from the mains, as that will be differential
mode.
Whilst the common mode is more likely to get radiated, the differential
mode noise can get converted to common mode by unbalances beyond the
clip on ferrite or toroidal transformer.
Woody
Dec 27, 2016, 4:59:29 AM12/27/16
to
"Scott" <newsg...@gefion.myzen.co.uk> wrote in message
news:jb636cd0nvohf5rsg...@4ax.com...
Interesting to read the details of the transformer. The fact that it
has a minimum load rating and that it is dimmable does suggest that it
is not just a transformer alone. You cannot normally run a transformer
through a dimmer, the dimmer would have to be a low voltage type
fitted after the transformer.
This item
http://www.ledlights4less.co.uk/index.php/mr16-leds/mr16-12v-led-transformer-issues.html
talks about transformer types and as you will see suggests, as I did,
that you try replacing one LED on each circuit with a halogen. At
least this would give some idea as th whether it is the supply or the
lamp that is causing the trouble.
Your transmitter link didn't work as it was non-specific. Do not that
almost all DAB sites use directional aerials so even if a new one has
opened locally there is nothing to say you are actually receiving that
site.
news:jb636cd0nvohf5rsg...@4ax.com...
has a minimum load rating and that it is dimmable does suggest that it
is not just a transformer alone. You cannot normally run a transformer
through a dimmer, the dimmer would have to be a low voltage type
fitted after the transformer.
This item
http://www.ledlights4less.co.uk/index.php/mr16-leds/mr16-12v-led-transformer-issues.html
talks about transformer types and as you will see suggests, as I did,
that you try replacing one LED on each circuit with a halogen. At
least this would give some idea as th whether it is the supply or the
lamp that is causing the trouble.
Your transmitter link didn't work as it was non-specific. Do not that
almost all DAB sites use directional aerials so even if a new one has
opened locally there is nothing to say you are actually receiving that
site.
Scott
Dec 27, 2016, 5:44:08 AM12/27/16
to
On Tue, 27 Dec 2016 09:59:29 -0000, "Woody" <harro...@ntlworld.com>
wrote:
I can't say it's exactly the same, but it looks the same. I was told
at the time it was better than an electronic transformer and would
last as long as the building itself!!!
any issue whatsoever. I cannot see how the supply can be the problem.
Or am I missing something?
individual transmitter (Glasgow Hilton Hotel). I appreciate there is
speculation on my part but the DAB signal strength seems to have
increased recently. It could be another relay or another change. I
know they are trying to boost DAB signal in Glasgow.
Thanks for your help. I have written to the suppliers (LED Hut) to
ask about EMC compliance.
wrote:
at the time it was better than an electronic transformer and would
last as long as the building itself!!!
>
>This item
>http://www.ledlights4less.co.uk/index.php/mr16-leds/mr16-12v-led-transformer-issues.html
>talks about transformer types and as you will see suggests, as I did,
>that you try replacing one LED on each circuit with a halogen. At
>least this would give some idea as th whether it is the supply or the
>lamp that is causing the trouble.
But the same transformer ran halogen bulbs for several years without
>This item
>http://www.ledlights4less.co.uk/index.php/mr16-leds/mr16-12v-led-transformer-issues.html
>talks about transformer types and as you will see suggests, as I did,
>that you try replacing one LED on each circuit with a halogen. At
>least this would give some idea as th whether it is the supply or the
>lamp that is causing the trouble.
any issue whatsoever. I cannot see how the supply can be the problem.
Or am I missing something?
>
>Your transmitter link didn't work as it was non-specific. Do not that
>almost all DAB sites use directional aerials so even if a new one has
>opened locally there is nothing to say you are actually receiving that
>site.
I see that today. When I copied the link it was showing the
>Your transmitter link didn't work as it was non-specific. Do not that
>almost all DAB sites use directional aerials so even if a new one has
>opened locally there is nothing to say you are actually receiving that
>site.
individual transmitter (Glasgow Hilton Hotel). I appreciate there is
speculation on my part but the DAB signal strength seems to have
increased recently. It could be another relay or another change. I
know they are trying to boost DAB signal in Glasgow.
Thanks for your help. I have written to the suppliers (LED Hut) to
ask about EMC compliance.
David Woolley
Dec 27, 2016, 6:09:35 AM12/27/16
to
On 27/12/16 10:44, Scott wrote:
> Thanks for your help. I have written to the suppliers (LED Hut) to
> ask about EMC compliance.
I'm sure they won't have sold anything that they didn't believe met the
> Thanks for your help. I have written to the suppliers (LED Hut) to
> ask about EMC compliance.
EU EMC directives. They are very unlikely to have the resources to
independently test.
As I said before, complying with the EMC directive doesn't mean that the
device won't cause radio interference. The limits are set based on
normal domestic use with an outdoor aerial in the official coverage area
of the transmitter. The allowed noise levels are significantly above
those you would get if there were a global power cut. Radio amateurs
have been complaining about many modern devices for a long time because
they want to be able receive signals that are limited only by natural noise.
Also, the tests will have been done in an ideal installation. The
chances are that the noise power is going down the 12V line, not being
radiated by the LED bulb itself, and it is imperfections in that line
which are resulting in its acting as an antenna.
Scott
Dec 27, 2016, 6:38:50 AM12/27/16
to
On Tue, 27 Dec 2016 11:09:29 +0000, David Woolley
<da...@ex.djwhome.demon.invalid> wrote:
>On 27/12/16 10:44, Scott wrote:
>> Thanks for your help. I have written to the suppliers (LED Hut) to
>> ask about EMC compliance.
>
>I'm sure they won't have sold anything that they didn't believe met the
>EU EMC directives. They are very unlikely to have the resources to
>independently test.
The Telegraph does not share your optimism:
<da...@ex.djwhome.demon.invalid> wrote:
>On 27/12/16 10:44, Scott wrote:
>> Thanks for your help. I have written to the suppliers (LED Hut) to
>> ask about EMC compliance.
>
>I'm sure they won't have sold anything that they didn't believe met the
>EU EMC directives. They are very unlikely to have the resources to
>independently test.
http://www.telegraph.co.uk/technology/advice/11312589/Problems-with-LED-bulbs-and-DAB-radio.html
>
>As I said before, complying with the EMC directive doesn't mean that the
>device won't cause radio interference. The limits are set based on
>normal domestic use with an outdoor aerial in the official coverage area
>of the transmitter. The allowed noise levels are significantly above
>those you would get if there were a global power cut. Radio amateurs
>have been complaining about many modern devices for a long time because
>they want to be able receive signals that are limited only by natural noise.
I have never heard of any DAB radio used with an outdoor aerial.
>As I said before, complying with the EMC directive doesn't mean that the
>device won't cause radio interference. The limits are set based on
>normal domestic use with an outdoor aerial in the official coverage area
>of the transmitter. The allowed noise levels are significantly above
>those you would get if there were a global power cut. Radio amateurs
>have been complaining about many modern devices for a long time because
>they want to be able receive signals that are limited only by natural noise.
Indeed, can you buy a portable DAB radio fitted with a coaxial socket?
>
>Also, the tests will have been done in an ideal installation. The
>chances are that the noise power is going down the 12V line, not being
>radiated by the LED bulb itself, and it is imperfections in that line
>which are resulting in its acting as an antenna.
Would a ferrite choke assist?
>Also, the tests will have been done in an ideal installation. The
>chances are that the noise power is going down the 12V line, not being
>radiated by the LED bulb itself, and it is imperfections in that line
>which are resulting in its acting as an antenna.
Bill Wright
Dec 27, 2016, 7:03:44 AM12/27/16
to
On 26/12/2016 14:39, Scott wrote:
> They are MR16 lamps (14 in total). I'm also going to write to the
> the box due to a 'printing error' I am not very confident about any of
> the information I am being given..
>
I suggest you replace some of the bulbs with others of a reputable make
and see what happens.
Bill
> They are MR16 lamps (14 in total). I'm also going to write to the
> supplier to see if they are EMC compliant. No mention of this on the
> box (however, as the wattage and halogen equivalence are both wrong on
> the box due to a 'printing error' I am not very confident about any of
> the information I am being given..
>
I suggest you replace some of the bulbs with others of a reputable make
and see what happens.
Bill
Bill Wright
Dec 27, 2016, 7:09:15 AM12/27/16
to
On 26/12/2016 14:45, Martin wrote:
>
> Our street is lit with LED lamps, but no problems with DAB radio.
>
aerial when tuned to an extremely weak DAB signal shows very slight
degradation. On a mediocre signal there is no effect.
Bill
Bill Wright
Dec 27, 2016, 7:11:15 AM12/27/16
to
> A quick test by putting a 10W LED flood in contact with the DAB wire
> aerial when tuned to an extremely weak DAB signal shows very slight
> degradation. On a mediocre signal there is no effect.
>
> Bill
powered the effect is the same.
Bill
David Woolley
Dec 27, 2016, 7:31:45 AM12/27/16
to
On 27/12/16 11:38, Scott wrote:
> On Tue, 27 Dec 2016 11:09:29 +0000, David Woolley
> <da...@ex.djwhome.demon.invalid> wrote:
>
>> On 27/12/16 10:44, Scott wrote:
>>> Thanks for your help. I have written to the suppliers (LED Hut) to
>>> ask about EMC compliance.
>>
>> I'm sure they won't have sold anything that they didn't believe met the
>> EU EMC directives. They are very unlikely to have the resources to
>> independently test.
> The Telegraph does not share your optimism:
> http://www.telegraph.co.uk/technology/advice/11312589/Problems-with-LED-bulbs-and-DAB-radio.html
Cheap ones tend to be sold on Ebay, or market stall, not through
> On Tue, 27 Dec 2016 11:09:29 +0000, David Woolley
> <da...@ex.djwhome.demon.invalid> wrote:
>
>> On 27/12/16 10:44, Scott wrote:
>>> Thanks for your help. I have written to the suppliers (LED Hut) to
>>> ask about EMC compliance.
>>
>> I'm sure they won't have sold anything that they didn't believe met the
>> EU EMC directives. They are very unlikely to have the resources to
>> independently test.
> The Telegraph does not share your optimism:
> http://www.telegraph.co.uk/technology/advice/11312589/Problems-with-LED-bulbs-and-DAB-radio.html
specialist suppliers.
> I have never heard of any DAB radio used with an outdoor aerial.
> Indeed, can you buy a portable DAB radio fitted with a coaxial socket?
external DAB antennas. Whilst sets may not have antenna sockets, it is
unfortunately the case that the use of indoor antennas produces such
uncontrolled signal quality that the enforcement authorities will not
generally be interested and the EMC compliance levels are set for good
outdoor aerials, not for kitchen worktop installations.
>>
>> Also, the tests will have been done in an ideal installation. The
>> chances are that the noise power is going down the 12V line, not being
>> radiated by the LED bulb itself, and it is imperfections in that line
>> which are resulting in its acting as an antenna.
> Would a ferrite choke assist?
them are underspecified to allow them to be properly selected for more
demanding work, so I would try one first.
However, the signal imposed on the cable will be balanced, and the
ferrites only deal with unbalanced signals. Whilst most radiation will
happen as a result of unbalance, that unbalance may not happen until
past the location of the filter.
The cheapest way of solving the issue is likely to be to buy will known
brands, like Philips (although I think they have been take over
recently), or if you can find them, use 700mA DC lamps and then buy a
high quality driver.
To fully filter the cable you will need a filter that does differential
and common mode. Normally such filters are internal to equipment, not
separate black boxes. Also, they are more likely to be designed for
mains voltage, with ones for 12V being done with discrete components.
Examples of ones designed for mains voltages can be found at:
<https://www.rapidonline.com/chassis-mount-filters>. At 12V, currents
will be higher and the acceptable voltage drop lower.
>
Scott
Dec 27, 2016, 7:54:16 AM12/27/16
to
On Tue, 27 Dec 2016 12:31:38 +0000, David Woolley
supplier the importer. Do they have to supply a certificate of
compliance on request?
systems as a recall, though I think this was premised on an outdoor
aerial.
disposing of my toroidal transformers or can they be 'driven' from
12V?
<da...@ex.djwhome.demon.invalid> wrote:
>On 27/12/16 11:38, Scott wrote:
>> On Tue, 27 Dec 2016 11:09:29 +0000, David Woolley
>> <da...@ex.djwhome.demon.invalid> wrote:
>>
>>> On 27/12/16 10:44, Scott wrote:
>>>> Thanks for your help. I have written to the suppliers (LED Hut) to
>>>> ask about EMC compliance.
>>>
>>> I'm sure they won't have sold anything that they didn't believe met the
>>> EU EMC directives. They are very unlikely to have the resources to
>>> independently test.
>> The Telegraph does not share your optimism:
>> http://www.telegraph.co.uk/technology/advice/11312589/Problems-with-LED-bulbs-and-DAB-radio.html
>
>Cheap ones tend to be sold on Ebay, or market stall, not through
>specialist suppliers.
I get the impression that these lamps were 'own brand' making the
>On 27/12/16 11:38, Scott wrote:
>> On Tue, 27 Dec 2016 11:09:29 +0000, David Woolley
>> <da...@ex.djwhome.demon.invalid> wrote:
>>
>>> On 27/12/16 10:44, Scott wrote:
>>>> Thanks for your help. I have written to the suppliers (LED Hut) to
>>>> ask about EMC compliance.
>>>
>>> I'm sure they won't have sold anything that they didn't believe met the
>>> EU EMC directives. They are very unlikely to have the resources to
>>> independently test.
>> The Telegraph does not share your optimism:
>> http://www.telegraph.co.uk/technology/advice/11312589/Problems-with-LED-bulbs-and-DAB-radio.html
>
>Cheap ones tend to be sold on Ebay, or market stall, not through
>specialist suppliers.
supplier the importer. Do they have to supply a certificate of
compliance on request?
>
>> I have never heard of any DAB radio used with an outdoor aerial.
>> Indeed, can you buy a portable DAB radio fitted with a coaxial socket?
>
>DAB was actually designed for car radios, and you can certainly get
>external DAB antennas. Whilst sets may not have antenna sockets, it is
>unfortunately the case that the use of indoor antennas produces such
>uncontrolled signal quality that the enforcement authorities will not
>generally be interested and the EMC compliance levels are set for good
>outdoor aerials, not for kitchen worktop installations.
>
I forgot about cars. They were also for 'CD quality sound' on hifi
>> I have never heard of any DAB radio used with an outdoor aerial.
>> Indeed, can you buy a portable DAB radio fitted with a coaxial socket?
>
>DAB was actually designed for car radios, and you can certainly get
>external DAB antennas. Whilst sets may not have antenna sockets, it is
>unfortunately the case that the use of indoor antennas produces such
>uncontrolled signal quality that the enforcement authorities will not
>generally be interested and the EMC compliance levels are set for good
>outdoor aerials, not for kitchen worktop installations.
>
systems as a recall, though I think this was premised on an outdoor
aerial.
>>>
>>> Also, the tests will have been done in an ideal installation. The
>>> chances are that the noise power is going down the 12V line, not being
>>> radiated by the LED bulb itself, and it is imperfections in that line
>>> which are resulting in its acting as an antenna.
>
>> Would a ferrite choke assist?
>
>They are cheap, and for VHF, most will be suitable, although a lot of
>them are underspecified to allow them to be properly selected for more
>demanding work, so I would try one first.
>
>However, the signal imposed on the cable will be balanced, and the
>ferrites only deal with unbalanced signals. Whilst most radiation will
>happen as a result of unbalance, that unbalance may not happen until
>past the location of the filter.
Okay.
>>> Also, the tests will have been done in an ideal installation. The
>>> chances are that the noise power is going down the 12V line, not being
>>> radiated by the LED bulb itself, and it is imperfections in that line
>>> which are resulting in its acting as an antenna.
>
>> Would a ferrite choke assist?
>
>They are cheap, and for VHF, most will be suitable, although a lot of
>them are underspecified to allow them to be properly selected for more
>demanding work, so I would try one first.
>
>However, the signal imposed on the cable will be balanced, and the
>ferrites only deal with unbalanced signals. Whilst most radiation will
>happen as a result of unbalance, that unbalance may not happen until
>past the location of the filter.
>
>The cheapest way of solving the issue is likely to be to buy will known
>brands, like Philips (although I think they have been take over
>recently), or if you can find them, use 700mA DC lamps and then buy a
>high quality driver.
I think John Lewis have the Philips ones. Would this involve
>The cheapest way of solving the issue is likely to be to buy will known
>brands, like Philips (although I think they have been take over
>recently), or if you can find them, use 700mA DC lamps and then buy a
>high quality driver.
disposing of my toroidal transformers or can they be 'driven' from
12V?
>
>To fully filter the cable you will need a filter that does differential
>and common mode. Normally such filters are internal to equipment, not
>separate black boxes. Also, they are more likely to be designed for
>mains voltage, with ones for 12V being done with discrete components.
>
>Examples of ones designed for mains voltages can be found at:
><https://www.rapidonline.com/chassis-mount-filters>. At 12V, currents
>will be higher and the acceptable voltage drop lower.
>>
Restoring the halogen bulbs might be the most cost-effective option.
>To fully filter the cable you will need a filter that does differential
>and common mode. Normally such filters are internal to equipment, not
>separate black boxes. Also, they are more likely to be designed for
>mains voltage, with ones for 12V being done with discrete components.
>
>Examples of ones designed for mains voltages can be found at:
><https://www.rapidonline.com/chassis-mount-filters>. At 12V, currents
>will be higher and the acceptable voltage drop lower.
>>
Scott
Dec 27, 2016, 7:55:45 AM12/27/16
to
Lumilife in terms of reputation?
Jim Lesurf
Dec 27, 2016, 7:57:46 AM12/27/16
to
In article <68636ch7p50hnrhcm...@4ax.com>, Scott
> As the lights nearest the radio cause the greatest problem and
> all the transformers are together - and connected to the lighting
> circuit of course - this seems unlikely.
By default, assume that the intereference needs to be dealt with as near to
the actual source as possible. In this case it sounds like it means each
individual LED lamp. Putting a filter at the transformer may reduce the
effect but not cure it.
If you use something like a ferrite clamp/ring at a distance along the
wiring the lamps may simply radiate from the wiring between lamp and
ferrite. So the general rule is to fix problems 'at source' so far as
possible.
The snag is that it may be the case that each lamp needs individual
treatment.
You *might* find that twisting the wiring may reduce radiate interference.
However this all sounds like the lamps aren't fit for your purpose / use.
<newsg...@gefion.myzen.co.uk> wrote:
> There was no problem when the transformer was running halogen bulbs. Can
> the interference be passed backwards through the transformer into the
> mains?
Yes, that may happen. Can't say more due to lack of detailed information.
> There was no problem when the transformer was running halogen bulbs. Can
> the interference be passed backwards through the transformer into the
> mains?
> As the lights nearest the radio cause the greatest problem and
> all the transformers are together - and connected to the lighting
> circuit of course - this seems unlikely.
the actual source as possible. In this case it sounds like it means each
individual LED lamp. Putting a filter at the transformer may reduce the
effect but not cure it.
If you use something like a ferrite clamp/ring at a distance along the
wiring the lamps may simply radiate from the wiring between lamp and
ferrite. So the general rule is to fix problems 'at source' so far as
possible.
The snag is that it may be the case that each lamp needs individual
treatment.
You *might* find that twisting the wiring may reduce radiate interference.
However this all sounds like the lamps aren't fit for your purpose / use.
David Woolley
Dec 27, 2016, 9:48:16 AM12/27/16
to
On 27/12/16 12:54, Scott wrote:
> I think John Lewis have the Philips ones. Would this involve
> disposing of my toroidal transformers or can they be 'driven' from
> 12V?
MR16 and GU10 bulbs have different bases. The 12V MR16 ones are, I
> I think John Lewis have the Philips ones. Would this involve
> disposing of my toroidal transformers or can they be 'driven' from
> 12V?
believe, pins, but the 240V GU10 ones are mushrooms.
Mark Carver
Dec 27, 2016, 9:55:34 AM12/27/16
to
On 27/12/2016 10:44, Scott wrote:
> I see that today. When I copied the link it was showing the
> individual transmitter (Glasgow Hilton Hotel). I appreciate there is
> speculation on my part but the DAB signal strength seems to have
> increased recently. It could be another relay or another change. I
> know they are trying to boost DAB signal in Glasgow.
Glasgow William St (aka Glasgow Hilton (Hotel)) is more or less omni
> I see that today. When I copied the link it was showing the
> individual transmitter (Glasgow Hilton Hotel). I appreciate there is
> speculation on my part but the DAB signal strength seems to have
> increased recently. It could be another relay or another change. I
> know they are trying to boost DAB signal in Glasgow.
directional, except for a 6ish dB null in an arc between due south and
due west.
https://www.ofcom.org.uk/spectrum/information/radio-tech-parameters
--
Mark
Please replace invalid and invalid with gmx and net to reply.
Jim Lesurf
Dec 27, 2016, 11:54:53 AM12/27/16
to
In article <vtg46c5vp4gk1fonj...@4ax.com>, Scott
own 'internal' circuitry to control their behavious are something different
again. We don't know exactly what the 'power supply' contains or how it
would react to these differences.
So although it seems likely that the LEDs are producing the interference,
that is not certain.
<newsg...@gefion.myzen.co.uk> wrote:
> But the same transformer ran halogen bulbs for several years without any
> issue whatsoever. I cannot see how the supply can be the problem. Or am
> I missing something?
Halogen bulbs are essentially resistors. LEDs are not. And LEDs with their
> But the same transformer ran halogen bulbs for several years without any
> issue whatsoever. I cannot see how the supply can be the problem. Or am
> I missing something?
own 'internal' circuitry to control their behavious are something different
again. We don't know exactly what the 'power supply' contains or how it
would react to these differences.
So although it seems likely that the LEDs are producing the interference,
that is not certain.
Brian-Gaff
Dec 27, 2016, 12:12:15 PM12/27/16
to
What you need is a small scanning radio with an am output. I used to have
one when I could see and it was very easy to find nasty interfering devices
with that device.
Probably loads on Ebay, Need to cover band 3 for this use but a dc to 1 gig
one will be very handy fro tracking nasty noises down.
Brian
--
From the Sofa of Brian Gaff Reply address is active
Remember, if you don't like where I post
or what I say, you don't have to
read my posts! :-)
one when I could see and it was very easy to find nasty interfering devices
with that device.
Probably loads on Ebay, Need to cover band 3 for this use but a dc to 1 gig
one will be very handy fro tracking nasty noises down.
Brian
--
From the Sofa of Brian Gaff Reply address is active
Remember, if you don't like where I post
or what I say, you don't have to
read my posts! :-)
"Scott" <newsg...@gefion.myzen.co.uk> wrote in message
news:m7626c9n1ipi9nt21...@4ax.com...
Brian-Gaff
Dec 27, 2016, 12:18:30 PM12/27/16
to
Could well be fakes then. they tend to sell seconds this way I am given to
understand.
Unfortunately, one of the ways to get apparently more light from an led is
to operate them in a pulsed mode resting some while others give light
allowing time for cooling so they can be run over their rated steady state
rating.
I've often wondered why they do this, surely the answer is to just use leds
that can handle the dissipation in the first place?
It may well be possible to snuff such interference with some kind of filter
in each light.
>>signal on DAB? There is usually somewhere in the menu system a signal
>>strength indication
> Yes - signal error between varies 3 and 5. I'm in a top floor flat so
> DAB reception is not normally a problem.
>>- does this indication vary between lights on and
>>lights off?
> Yes - with all the lights on it goes to 'No audio'.
>>Does the indication vary with the number of lamps lit?
> Yes.
>>What is the nature of the DAB problem - does it go to bubbling mud or
>>does the radio just mute?
> It deteriorates to bubbling mud as the lights are turned on. The ones
> closest cause the biggest problem.
>>That's a start.
> And thanks for that.
understand.
Unfortunately, one of the ways to get apparently more light from an led is
to operate them in a pulsed mode resting some while others give light
allowing time for cooling so they can be run over their rated steady state
rating.
I've often wondered why they do this, surely the answer is to just use leds
that can handle the dissipation in the first place?
It may well be possible to snuff such interference with some kind of filter
in each light.
Brian
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"Scott" <newsg...@gefion.myzen.co.uk> wrote in message
news:47a26c5ijh2ggja64...@4ax.com...
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"Scott" <newsg...@gefion.myzen.co.uk> wrote in message
> On Mon, 26 Dec 2016 13:59:55 -0000, "Woody" <harro...@ntlworld.com>
> wrote:
>
>>
>>"Scott" <newsg...@gefion.myzen.co.uk> wrote in message
>>news:m7626c9n1ipi9nt21...@4ax.com...
>>>I installed LED spotlights in the kitchen and when they are all on
>>>the
>>> DAB radio stops working. I am wondering if this is due to:
>>>
>>> 1. A general problem with LED lighting (in which case is it fit for
>>> purpose for domestic use?)
>>> 2. A single faulty bulb
>>> 3. A particular issue with 12 Volt bulbs
>>>
>>> I should explain this is a somewhat unusual installation. The
>>> lights
>>> are powered by torroidal transformers (for which I am assured there
>>> is
>>> no minimum load). The transformers are a long way from the radio
>>> and
>>> have never previously caused difficulties, so I am convinced the
>>> problems lie with the bulbs themselves.
>>>
>>> A quick search suggests that the problem could be Electromagnetic
>>> Compatibility (EMC) or lack of it.
>>>
>>> Any ideas among the experts?
>>
>>Questions in advance of the expert start: do you normally get a good
> wrote:
>
>>
>>"Scott" <newsg...@gefion.myzen.co.uk> wrote in message
>>news:m7626c9n1ipi9nt21...@4ax.com...
>>>I installed LED spotlights in the kitchen and when they are all on
>>>the
>>> DAB radio stops working. I am wondering if this is due to:
>>>
>>> 1. A general problem with LED lighting (in which case is it fit for
>>> purpose for domestic use?)
>>> 2. A single faulty bulb
>>> 3. A particular issue with 12 Volt bulbs
>>>
>>> I should explain this is a somewhat unusual installation. The
>>> lights
>>> are powered by torroidal transformers (for which I am assured there
>>> is
>>> no minimum load). The transformers are a long way from the radio
>>> and
>>> have never previously caused difficulties, so I am convinced the
>>> problems lie with the bulbs themselves.
>>>
>>> A quick search suggests that the problem could be Electromagnetic
>>> Compatibility (EMC) or lack of it.
>>>
>>> Any ideas among the experts?
>>
>>signal on DAB? There is usually somewhere in the menu system a signal
>>strength indication
> Yes - signal error between varies 3 and 5. I'm in a top floor flat so
> DAB reception is not normally a problem.
>>- does this indication vary between lights on and
>>lights off?
> Yes - with all the lights on it goes to 'No audio'.
>>Does the indication vary with the number of lamps lit?
> Yes.
>>What is the nature of the DAB problem - does it go to bubbling mud or
>>does the radio just mute?
> It deteriorates to bubbling mud as the lights are turned on. The ones
> closest cause the biggest problem.
>>That's a start.
> And thanks for that.
Brian-Gaff
Dec 27, 2016, 12:25:10 PM12/27/16
to
No the constant current device will still be needed. Leds do not like being
run without some current mimiting, hence the resistor in most situations,
but to be operated in pulse mode with a very well controlled current some
switch mode circuit is used. It will not affect it whether its on dc or ac
as there is already rectification in the uniit for that purpose.
When I read up on LED lighting an I decided not to bother with them until
the tech changes. They seem to be making CFLs now which do not make the
interference the early ones had so maybe there is hope. Being a short wave
fan I despair at the rubbish our devices chuck out these days. I can control
mine but not everyone elses.
> live in a top floor flat. A new fill-in transmitter has recently been
> opened.
> lights with no thought of twisted pairs. They are certainly together
> as it is two core flex.
run without some current mimiting, hence the resistor in most situations,
but to be operated in pulse mode with a very well controlled current some
switch mode circuit is used. It will not affect it whether its on dc or ac
as there is already rectification in the uniit for that purpose.
When I read up on LED lighting an I decided not to bother with them until
the tech changes. They seem to be making CFLs now which do not make the
interference the early ones had so maybe there is hope. Being a short wave
fan I despair at the rubbish our devices chuck out these days. I can control
mine but not everyone elses.
Brian
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"Scott" <newsg...@gefion.myzen.co.uk> wrote in message
news:bhc26clr1fps2sjhh...@4ax.com...
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"Scott" <newsg...@gefion.myzen.co.uk> wrote in message
> On Mon, 26 Dec 2016 14:53:01 +0000, David Woolley
> <da...@ex.djwhome.demon.invalid> wrote:
>
>>On 26/12/16 14:39, Scott wrote:
> <da...@ex.djwhome.demon.invalid> wrote:
>
>>On 26/12/16 14:39, Scott wrote:
>>> I'm also going to write to the
>>> supplier to see if they are EMC compliant. No mention of this on the
>>> box
>>
>>> supplier to see if they are EMC compliant. No mention of this on the
>>> box
>>
>>The E symbol on the box is the claim of compliance. If they do not have
>>that, they should not have been on sale.
>
> Do you mean 'CE'? This is marked on the box.
>>that, they should not have been on sale.
>
>>
>>However, as the other questions are hinting at, EMC compliance basically
>>only means that they generate a commercially acceptable level of noise,
>>not that that noise is way below the natural background. If your
>>reception is marginal, they will push you over the limit.
>
> I think the reception is pretty good - usually in the high 90s. I
>>However, as the other questions are hinting at, EMC compliance basically
>>only means that they generate a commercially acceptable level of noise,
>>not that that noise is way below the natural background. If your
>>reception is marginal, they will push you over the limit.
>
> live in a top floor flat. A new fill-in transmitter has recently been
> opened.
>>
>>Incidentally, it is not the LEDs that cause the RFI, but the switch mode
>>power supply that generates a constant current for them. If you want to
>>control RFI, you should install LED's with no built in power supply and
>>use a, well suppressed, external, constant current power supply. They
>>will no longer be standard 12V bulbs, but rather, typically 350mA or
>>700mA devices, and you will typically series connect them, rather than
>>parallel
>
> As I mentioned, these are run from three toroidal transormers. I
>>Incidentally, it is not the LEDs that cause the RFI, but the switch mode
>>power supply that generates a constant current for them. If you want to
>>control RFI, you should install LED's with no built in power supply and
>>use a, well suppressed, external, constant current power supply. They
>>will no longer be standard 12V bulbs, but rather, typically 350mA or
>>700mA devices, and you will typically series connect them, rather than
>>parallel
>
> appreciate this means they receive AC supply but do they still have
> built-in switched mode power supply? I see they are AC or DC so could
> I fit a rectifier to the transformer output and would running on DC
> make a difference?
>>
> built-in switched mode power supply? I see they are AC or DC so could
> I fit a rectifier to the transformer output and would running on DC
> make a difference?
>>
>>It is possible that your ELV wiring has not been done well. To minimise
>>radiation, you should use twisted pair, of a suitable current rating, or
>>at least ensure that both wires of the pair are together.
>>
> It is very likely as the wiring was done several years ago for halogen
>>radiation, you should use twisted pair, of a suitable current rating, or
>>at least ensure that both wires of the pair are together.
>>
> lights with no thought of twisted pairs. They are certainly together
> as it is two core flex.
Scott
Dec 27, 2016, 2:04:53 PM12/27/16
to
https://www.thelightbulbshop.co.uk/Shop/Non-DimmableMR16LEDBulbs/Product/8-50WCoreProLEDSpotLVMR16GU53.aspx?gclid=CLvFkeuHldECFYXGGwodWl8Oiw
Seems it is also called GU5.3. It has always puzzled me why the 12
Volt ones have smaller pins than mains voltage when by definition the
current is higher.
Dave W
Dec 28, 2016, 6:35:54 AM12/28/16
to
news:47a26c5ijh2ggja64...@4ax.com...
> On Mon, 26 Dec 2016 13:59:55 -0000, "Woody" <harro...@ntlworld.com>
> wrote:
>
>>
> On Mon, 26 Dec 2016 13:59:55 -0000, "Woody" <harro...@ntlworld.com>
> wrote:
>
>>
>>"Scott" <newsg...@gefion.myzen.co.uk> wrote in message
> supplier to see if they are EMC compliant. No mention of this on the
> box (however, as the wattage and halogen equivalence are both wrong on
> the box due to a 'printing error' I am not very confident about any of
> the information I am being given..
As far as I can tell, you have a simple transformer providing 12V AC to each
> the box due to a 'printing error' I am not very confident about any of
> the information I am being given..
group of lamps. The lamps only run on 50Hz AC. They each have an internal
SMPS to drive the LEDs.
You could switch on just the worst bulb, then move the radio along the route
between the transformer and the bulb, to see whether the interference is
coming from the wire or just the bulb.
If it's the wire, you might be able to add a suppressor near each bulb but I
doubt if it would be economically viable owing to the high current peaks
involved. Or maybe the wire could be screened. I doubt that the interference
would get past the transformer into the mains, especially as you say the
nearest bulbs give the most interference.
If it's the bulb alone, assuming it's a genuine Philips, you're stuck.
--
Dave W
Scott
Dec 28, 2016, 11:41:20 AM12/28/16
to
On Wed, 28 Dec 2016 11:33:44 -0000, "Dave W" <dave...@yahoo.co.uk>
Yes, essentially.
nearest the radio causes the most interference.
potential replacement. I see they are now in John Lewis.
>
>You could switch on just the worst bulb, then move the radio along the route
>between the transformer and the bulb, to see whether the interference is
>coming from the wire or just the bulb.
Don't think there is worst bulb. What I have found is that the group
>You could switch on just the worst bulb, then move the radio along the route
>between the transformer and the bulb, to see whether the interference is
>coming from the wire or just the bulb.
nearest the radio causes the most interference.
>
>If it's the wire, you might be able to add a suppressor near each bulb but I
>doubt if it would be economically viable owing to the high current peaks
>involved. Or maybe the wire could be screened. I doubt that the interference
>would get past the transformer into the mains, especially as you say the
>nearest bulbs give the most interference.
The bulbs are in a track so I could only suppress the track.
>If it's the wire, you might be able to add a suppressor near each bulb but I
>doubt if it would be economically viable owing to the high current peaks
>involved. Or maybe the wire could be screened. I doubt that the interference
>would get past the transformer into the mains, especially as you say the
>nearest bulbs give the most interference.
>
>If it's the bulb alone, assuming it's a genuine Philips, you're stuck.
Not Philips. The bulbs are Lumilife. I was suggesting Philips as a
>If it's the bulb alone, assuming it's a genuine Philips, you're stuck.
potential replacement. I see they are now in John Lewis.
Scott
Dec 28, 2016, 3:42:33 PM12/28/16
to
On Tue, 27 Dec 2016 17:12:14 -0000, "Brian-Gaff"
<bri...@blueyonder.co.uk> wrote:
>What you need is a small scanning radio with an am output. I used to have
>one when I could see and it was very easy to find nasty interfering devices
>with that device.
> Probably loads on Ebay, Need to cover band 3 for this use but a dc to 1 gig
>one will be very handy fro tracking nasty noises down.
> Brian
I tried a Pure One Mini (batteries) and it was much less affected.
<bri...@blueyonder.co.uk> wrote:
>What you need is a small scanning radio with an am output. I used to have
>one when I could see and it was very easy to find nasty interfering devices
>with that device.
> Probably loads on Ebay, Need to cover band 3 for this use but a dc to 1 gig
>one will be very handy fro tracking nasty noises down.
> Brian
More modern piece of kit though. As I held it to the lamps the sound
deteriorated. However when I sat it beside the transformers it was
fine so I am assuming the spotlights are to blame.
Scott
Dec 30, 2016, 5:12:24 PM12/30/16
to
On Mon, 26 Dec 2016 14:39:03 +0000, Scott
<newsg...@gefion.myzen.co.uk> wrote:
[snip]
As a follow-up, I received a reply from LED Hut customer services
confirming this has happened with other customers and stating 'there
is now [sic] way of stopping the DAB radio interference with our
12-volt spotlights'.
They evaded my question whether these lamps are EMC complaint. .
<newsg...@gefion.myzen.co.uk> wrote:
[snip]
As a follow-up, I received a reply from LED Hut customer services
confirming this has happened with other customers and stating 'there
is now [sic] way of stopping the DAB radio interference with our
12-volt spotlights'.
They evaded my question whether these lamps are EMC complaint. .
Woody
Dec 30, 2016, 5:48:02 PM12/30/16
to
news:jmmd6ct8slliu4jgr...@4ax.com...
Do let us know what that 'way' is won't you, then we can show them up
as the ****** they are!
as the ****** they are!
Scott
Dec 31, 2016, 8:43:37 AM12/31/16
to
On Sat, 31 Dec 2016 11:36:54 +0100, Martin <m...@address.invalid> wrote:
>Complain to Ofcom?
Am I not more likely to be the one complained about if I install and
use equipment that causes radio interference? I thought the duty lay
with the user not the retailer.
Am I not more likely to be the one complained about if I install and
use equipment that causes radio interference? I thought the duty lay
with the user not the retailer.
Scott
Dec 31, 2016, 9:35:49 AM12/31/16
to
On Sat, 31 Dec 2016 15:27:30 +0100, Martin <m...@address.invalid> wrote:
>The retailer is breaking the law by selling non compliant equipment, you are the
>innocent victim.
Am I? If I contine to use equipment after I become aware of the issue
do I not have any duty of care to my neighbours? I'm glad I don't
live next door to you.
>innocent victim.
Am I? If I contine to use equipment after I become aware of the issue
do I not have any duty of care to my neighbours? I'm glad I don't
live next door to you.
Dave W
Dec 31, 2016, 11:36:38 AM12/31/16
to
news:9kq76c5e1iiaol8jm...@4ax.com...
I think you said you have three bulbs per transformer. The link to the
transformer you gave was for a 100W 24V. You have 12V but I assume the
transformers are still 100W. Each would have driven three 35W halogen bulbs,
so I assume your replacement LED bulbs give the equivalent light output,
i.e. the Lumilife 4.8W MR16.
I tried to find out more information about these. They are sold by many
firms online but all come from LED-hut. That site gives no indication about
where the bulbs come from, so it seems they are an imported 'own brand', and
there is no full specification available. You would do well to try three
Philips bulbs instead, although even Philips spec doesn't say anything about
RF interference.
They are the Philips CorePro LEDspot LV, available in two colour
temperatures: 4000 at 4.7W, and 3700 at 5.5W.
--
Dave W
transformer you gave was for a 100W 24V. You have 12V but I assume the
transformers are still 100W. Each would have driven three 35W halogen bulbs,
so I assume your replacement LED bulbs give the equivalent light output,
i.e. the Lumilife 4.8W MR16.
I tried to find out more information about these. They are sold by many
firms online but all come from LED-hut. That site gives no indication about
where the bulbs come from, so it seems they are an imported 'own brand', and
there is no full specification available. You would do well to try three
Philips bulbs instead, although even Philips spec doesn't say anything about
RF interference.
They are the Philips CorePro LEDspot LV, available in two colour
temperatures: 4000 at 4.7W, and 3700 at 5.5W.
--
Dave W
Woody
Dec 31, 2016, 12:06:43 PM12/31/16
to
"Dave W" <dave...@yahoo.co.uk> wrote in message
news:o48mqj$1j9e$1...@gioia.aioe.org...
Why do manufacturers choose 'odd' colour temperatures. If they are
replacing incandescent bulbs then they need to be around 2300K to
colour match, if they are replacing halogen then they need to be a bit
higher - somewhere around 2700-3000K. So why are Philips making a bulb
at 4000K which is more like the colur of a daylight white fluorescent
tube? Barmy to my mind.
I have just replaced six 35W GU10 bulbs in a fitting in my dining
room. The new LED bulbs are listed at 'warm white' but when I got them
home they were/are 3000K which is much brighter and whiter than the
bulbs they replaced. What is more the colour does not change as they
are dimmed, only the light level changes. Whilst it means you can see
your food better it doesn't look anything like so hospitable!
Scott
Dec 31, 2016, 12:13:01 PM12/31/16
to
On Sat, 31 Dec 2016 16:36:57 -0000, "Dave W" <dave...@yahoo.co.uk>
wrote:
[snip]
contain five spots and one contains four. The transformer in the link
was only for illustration. Each halogen spot was 50W. The Lumilife
bulbs are 7.5W on the website (though 6.5W on the box).
problem with DAB (for 12V lamps only). The bulbs come from China.
http://www.screwfix.com/p/philips-mr16-led-lamps-gu5-3-621lm-8-2w-3-pack/6415p
(I need a lot of light as it is high ceilings and these are the main
room lights.)
PS I have started a new thread on Philips.
wrote:
[snip]
>
>I think you said you have three bulbs per transformer. The link to the
>transformer you gave was for a 100W 24V. You have 12V but I assume the
>transformers are still 100W. Each would have driven three 35W halogen bulbs,
>so I assume your replacement LED bulbs give the equivalent light output,
>i.e. the Lumilife 4.8W MR16.
It was three transformers, one for each track. Two of the tracks
>I think you said you have three bulbs per transformer. The link to the
>transformer you gave was for a 100W 24V. You have 12V but I assume the
>transformers are still 100W. Each would have driven three 35W halogen bulbs,
>so I assume your replacement LED bulbs give the equivalent light output,
>i.e. the Lumilife 4.8W MR16.
contain five spots and one contains four. The transformer in the link
was only for illustration. Each halogen spot was 50W. The Lumilife
bulbs are 7.5W on the website (though 6.5W on the box).
>
>I tried to find out more information about these. They are sold by many
>firms online but all come from LED-hut. That site gives no indication about
>where the bulbs come from, so it seems they are an imported 'own brand', and
>there is no full specification available. You would do well to try three
>Philips bulbs instead, although even Philips spec doesn't say anything about
>RF interference.
Thanks for investigating. LED Hut seem to be conceding there is a
>I tried to find out more information about these. They are sold by many
>firms online but all come from LED-hut. That site gives no indication about
>where the bulbs come from, so it seems they are an imported 'own brand', and
>there is no full specification available. You would do well to try three
>Philips bulbs instead, although even Philips spec doesn't say anything about
>RF interference.
problem with DAB (for 12V lamps only). The bulbs come from China.
>
>They are the Philips CorePro LEDspot LV, available in two colour
>temperatures: 4000 at 4.7W, and 3700 at 5.5W.
Screwfix are doing three 8.2W units for £16.99
>They are the Philips CorePro LEDspot LV, available in two colour
>temperatures: 4000 at 4.7W, and 3700 at 5.5W.
http://www.screwfix.com/p/philips-mr16-led-lamps-gu5-3-621lm-8-2w-3-pack/6415p
(I need a lot of light as it is high ceilings and these are the main
room lights.)
PS I have started a new thread on Philips.
Scott
Dec 31, 2016, 12:19:13 PM12/31/16
to
On Sat, 31 Dec 2016 17:53:13 +0100, Martin <m...@address.invalid> wrote:
>Not sure what that has to do with anything.
>a) You were the innocent victim.
>b) Stop using the lamps
>c) Report the retailer to Ofcom
>d) Get a refund from the retailer.
It was a response to your apparent suggestion that I could not become
the subject of a complaint to Ofcom. However, as you raise the point
it appears Ofcom is not the correct forum for a complaint:
https://www.ofcom.org.uk/spectrum/interference-enforcement/interference-complaints
"The BBC is responsible for dealing with complaints of interference to
domestic television and radio reception except where the source is an
unlicensed broadcast station. Ofcom will offer advice and assistance,
and where appropriate investigate, where we receive reports of harmful
interference from consumers and citizens."
>a) You were the innocent victim.
>b) Stop using the lamps
>c) Report the retailer to Ofcom
>d) Get a refund from the retailer.
It was a response to your apparent suggestion that I could not become
the subject of a complaint to Ofcom. However, as you raise the point
it appears Ofcom is not the correct forum for a complaint:
https://www.ofcom.org.uk/spectrum/interference-enforcement/interference-complaints
"The BBC is responsible for dealing with complaints of interference to
domestic television and radio reception except where the source is an
unlicensed broadcast station. Ofcom will offer advice and assistance,
and where appropriate investigate, where we receive reports of harmful
interference from consumers and citizens."
Vir Campestris
Dec 31, 2016, 4:41:36 PM12/31/16
to
On 31/12/2016 16:53, Martin wrote:
> Not sure what that has to do with anything.
> a) You were the innocent victim.
> b) Stop using the lamps
> c) Report the retailer to Ofcom
> d) Get a refund from the retailer.
d) is easier than c). AIUI LED Hut are pretty good on duds.
> Not sure what that has to do with anything.
> a) You were the innocent victim.
> b) Stop using the lamps
> c) Report the retailer to Ofcom
> d) Get a refund from the retailer.
Andy
Jim Lesurf
Jan 1, 2017, 7:15:27 AM1/1/17
to
In article <o48og7$grq$1...@dont-email.me>, Woody <harro...@ntlworld.com>
wrote:
> Why do manufacturers choose 'odd' colour temperatures. If they are
> replacing incandescent bulbs then they need to be around 2300K to
> colour match, if they are replacing halogen then they need to be a bit
> higher - somewhere around 2700-3000K. So why are Philips making a bulb
> at 4000K which is more like the colur of a daylight white fluorescent
> tube? Barmy to my mind.
The history IIRC is that the early generations of high efficiency 'white'
LEDs use(d) blue/UV LEDs along with phosphors to convert some of that into
other wavelengths to get 'white'. The results tended to have to lean
towards the blue for efficiency reasons.
IEEE Spectrum did an article on this some time ago. One result of the above
is that many locations adopted the new LEDs for street lighting to save
power/money. They now realise those LEDs are uncomfortably 'blue' and need
replacing.
Later types give lower colour temperatures. But the early ones might be
cheaper to make at present. What I don't know is if it is still the case
that to get the 'warmer' temperatures you still end up with lower
efficiency and/or high cost.
wrote:
> Why do manufacturers choose 'odd' colour temperatures. If they are
> replacing incandescent bulbs then they need to be around 2300K to
> colour match, if they are replacing halogen then they need to be a bit
> higher - somewhere around 2700-3000K. So why are Philips making a bulb
> at 4000K which is more like the colur of a daylight white fluorescent
> tube? Barmy to my mind.
LEDs use(d) blue/UV LEDs along with phosphors to convert some of that into
other wavelengths to get 'white'. The results tended to have to lean
towards the blue for efficiency reasons.
IEEE Spectrum did an article on this some time ago. One result of the above
is that many locations adopted the new LEDs for street lighting to save
power/money. They now realise those LEDs are uncomfortably 'blue' and need
replacing.
Later types give lower colour temperatures. But the early ones might be
cheaper to make at present. What I don't know is if it is still the case
that to get the 'warmer' temperatures you still end up with lower
efficiency and/or high cost.
Max Demian
Jan 1, 2017, 9:33:42 AM1/1/17
to
On 01/01/2017 12:13, Jim Lesurf wrote:
> In article <o48og7$grq$1...@dont-email.me>, Woody <harro...@ntlworld.com>
> wrote:
>
>> Why do manufacturers choose 'odd' colour temperatures. If they are
>> replacing incandescent bulbs then they need to be around 2300K to
>> colour match, if they are replacing halogen then they need to be a bit
>> higher - somewhere around 2700-3000K. So why are Philips making a bulb
>> at 4000K which is more like the colur of a daylight white fluorescent
>> tube? Barmy to my mind.
>
> The history IIRC is that the early generations of high efficiency 'white'
> LEDs use(d) blue/UV LEDs along with phosphors to convert some of that into
> other wavelengths to get 'white'. The results tended to have to lean
> towards the blue for efficiency reasons.
>
> IEEE Spectrum did an article on this some time ago. One result of the above
> is that many locations adopted the new LEDs for street lighting to save
> power/money. They now realise those LEDs are uncomfortably 'blue' and need
> replacing.
Why does it matter with street lights? No-one (effectively) complained
> In article <o48og7$grq$1...@dont-email.me>, Woody <harro...@ntlworld.com>
> wrote:
>
>> Why do manufacturers choose 'odd' colour temperatures. If they are
>> replacing incandescent bulbs then they need to be around 2300K to
>> colour match, if they are replacing halogen then they need to be a bit
>> higher - somewhere around 2700-3000K. So why are Philips making a bulb
>> at 4000K which is more like the colur of a daylight white fluorescent
>> tube? Barmy to my mind.
>
> The history IIRC is that the early generations of high efficiency 'white'
> LEDs use(d) blue/UV LEDs along with phosphors to convert some of that into
> other wavelengths to get 'white'. The results tended to have to lean
> towards the blue for efficiency reasons.
>
> IEEE Spectrum did an article on this some time ago. One result of the above
> is that many locations adopted the new LEDs for street lighting to save
> power/money. They now realise those LEDs are uncomfortably 'blue' and need
> replacing.
about the (bluish) mercury lights or even low (yellow) and high (pink)
pressure sodium lights.
--
Max Demian
Woody
Jan 1, 2017, 10:32:10 AM1/1/17
to
"Jim Lesurf" <no...@audiomisc.co.uk> wrote in message
news:55f7982...@audiomisc.co.uk...
pressure lamps with the gold light - to LED any day. I don't
understand why but the 'daylight' white of LEDs doesn't seem to light
objects - especially people - in the same way that limited spectrum
lights do.
I remember as a child travelling back to Leicester from Chesterfield
having visited family and going through Derby where flourescent street
lights were the norm. It made it very difficult to see where you were
going especially if it was foggy, which suggests that colour has a
significant part to play.
I think however I may have accidently found out more about it. We have
a PIR switched lamp on our shed which has a habit of lighting up at
night for no apparent reason. To reduce consumption yesterday I
replaced the R7s 100W 78mm halogen fitting with a 20W LED reflector
unit, and I went outside last night to test it. What was immediately
obvious was that the LED lamp lit things that the light fell on but it
did not light 'around' objects in the same way that the previous flood
did. I think a lot of that is to do with the fact that the halogen
lamp worked properly in that the source was in front of the reflector
and the light was distributed: despite having what looks like a
reflector, the LEDs being behind the reflector do not actually 'use'
the reflector and thus works like a point source. Even though street
lights have a number of these point sources they still don't spread
the light in the same way and that is why I personally find them
unacceptable.
I have a R7s 118mm fitting at the front of the house in which I
replaced the halogen with a LED assembly of 6W rating. Whilst I do not
like the colour of the light emitted, as the source is in a similar
physical position to the tube that it replaced it uses the reflector
'properly' spreads the light in a much more visibly acceptable
pattern.
Jim Lesurf
Jan 1, 2017, 12:00:27 PM1/1/17
to
In article <MNSdnUV-zajZjvTF...@brightview.co.uk>, Max
Demian
of that issue of 'Spectrum', although I tend to bin them afer a few months
so this will be a matter of luck. Alteratively, the article may be on their
website.
Demian
<max_d...@bigfoot.com> wrote:
> >
> > IEEE Spectrum did an article on this some time ago. One result of the
> > above is that many locations adopted the new LEDs for street lighting
> > to save power/money. They now realise those LEDs are uncomfortably
> > 'blue' and need replacing.
> Why does it matter with street lights? No-one (effectively) complained
> about the (bluish) mercury lights or even low (yellow) and high (pink)
> pressure sodium lights.
Afraid I can't now recall the reasons given. I'll see if I can find my copy
> >
> > IEEE Spectrum did an article on this some time ago. One result of the
> > above is that many locations adopted the new LEDs for street lighting
> > to save power/money. They now realise those LEDs are uncomfortably
> > 'blue' and need replacing.
> Why does it matter with street lights? No-one (effectively) complained
> about the (bluish) mercury lights or even low (yellow) and high (pink)
> pressure sodium lights.
of that issue of 'Spectrum', although I tend to bin them afer a few months
so this will be a matter of luck. Alteratively, the article may be on their
website.
Jim Lesurf
Jan 1, 2017, 12:05:15 PM1/1/17
to
On 01 Jan, no...@audiomisc.co.uk wrote:
> > Why does it matter with street lights? No-one (effectively) complained
> > about the (bluish) mercury lights or even low (yellow) and high (pink)
> > pressure sodium lights.
> Afraid I can't now recall the reasons given. I'll see if I can find my
> copy of that issue of 'Spectrum', although I tend to bin them afer a few
> months so this will be a matter of luck. Alteratively, the article may
> be on their website.
Found it. Issue 10.16 of IEEE Spectrum "The early adopter blues" by Jeff
> > Why does it matter with street lights? No-one (effectively) complained
> > about the (bluish) mercury lights or even low (yellow) and high (pink)
> > pressure sodium lights.
> Afraid I can't now recall the reasons given. I'll see if I can find my
> copy of that issue of 'Spectrum', although I tend to bin them afer a few
> months so this will be a matter of luck. Alteratively, the article may
> be on their website.
Hecht. Not re-read it, but you may be able to find the details on the web.
Roderick Stewart
Jan 1, 2017, 1:52:27 PM1/1/17
to
On Sun, 1 Jan 2017 15:32:13 -0000, "Woody" <harro...@ntlworld.com>
wrote:
The difference you describe isn't really to do with the colour of the
LED lights, but the distribution. Fair comment, because they are
different and need dealing with differently, it's not a difference in
colour.
All my house lights are now LED, mostly bayonet fitting replacement
bulbs, but they do really need a different style of lampshade to work
most effectively because they don't radiate so much light towards the
connector end on account of the lump of electronics in the way. Nearly
all lampshades in the shops still seem to be of the open ended
cylinder type, presumably to allow airflow for hot bulbs, despite the
fact that not all bulbs are hot these days, so a ceiling fitting will
illuminate the area underneath it but not throw so much soft light via
the ceiling. The shades I like best for this purpose are the
upside-down "coolie" type, which don't give a direct view of the bulb
at all but throw all their light upwards onto the ceiling. They work
best with white ceilings of course.
As for colour, "warm white" around 3000K seems the most pleasing
replacement for conventional bulbs, so I avoid the ones described as
"daylight" around 6000K which give a very severe clinical look.
There's also a new one called "vintage" which is a long way below
3000K and looks like gaslight, which I suppose is the intention, but
it makes everything look very dingy. The LEDs in these "vintage" bulbs
are arranged in strips a bit like old-fashioned filaments and they've
somehow made the electronics smaller so there isn't that lump blocking
the light, which gives a much better distribution, but unfortunately
they don't seem to be available in any other colour (yet?).
Rod.
wrote:
LED lights, but the distribution. Fair comment, because they are
different and need dealing with differently, it's not a difference in
colour.
All my house lights are now LED, mostly bayonet fitting replacement
bulbs, but they do really need a different style of lampshade to work
most effectively because they don't radiate so much light towards the
connector end on account of the lump of electronics in the way. Nearly
all lampshades in the shops still seem to be of the open ended
cylinder type, presumably to allow airflow for hot bulbs, despite the
fact that not all bulbs are hot these days, so a ceiling fitting will
illuminate the area underneath it but not throw so much soft light via
the ceiling. The shades I like best for this purpose are the
upside-down "coolie" type, which don't give a direct view of the bulb
at all but throw all their light upwards onto the ceiling. They work
best with white ceilings of course.
As for colour, "warm white" around 3000K seems the most pleasing
replacement for conventional bulbs, so I avoid the ones described as
"daylight" around 6000K which give a very severe clinical look.
There's also a new one called "vintage" which is a long way below
3000K and looks like gaslight, which I suppose is the intention, but
it makes everything look very dingy. The LEDs in these "vintage" bulbs
are arranged in strips a bit like old-fashioned filaments and they've
somehow made the electronics smaller so there isn't that lump blocking
the light, which gives a much better distribution, but unfortunately
they don't seem to be available in any other colour (yet?).
Rod.
Max Demian
Jan 2, 2017, 2:27:55 PM1/2/17
to
On Mon, 02 Jan 2017 12:21:35 +0100, Martin <m...@address.invalid> wrote:
> On Sun, 01 Jan 2017 17:04:59 +0000 (GMT), Jim Lesurf
<no...@audiomisc.co.uk>
>
http://spectrum.ieee.org/green-tech/conservation/led-streetlights-are-g
iving-neighborhoods-the-blues
What moaning minnies. I've got two metres of RGB LED strip over my
living room window hooked up to a three knob dimmer so I can have any
colour I like. Maybe they could have a similar arrangement for street
lighting, radio controlled so they can adjust the colour to suit
people's tastes.
--
Max Demian
> On Sun, 01 Jan 2017 17:04:59 +0000 (GMT), Jim Lesurf
<no...@audiomisc.co.uk>
> wrote:
> >On 01 Jan, no...@audiomisc.co.uk wrote:
> >> > Why does it matter with street lights? No-one (effectively)
complained
> >> > about the (bluish) mercury lights or even low (yellow) and
high (pink)
> >> > pressure sodium lights.
> >
> >> Afraid I can't now recall the reasons given. I'll see if I can
find my
> >> copy of that issue of 'Spectrum', although I tend to bin them
afer a few
> >> months so this will be a matter of luck. Alteratively, the
article may
> >> be on their website.
> >
> >Found it. Issue 10.16 of IEEE Spectrum "The early adopter blues"
by Jeff
> >Hecht. Not re-read it, but you may be able to find the details on
the web.
> The article is here
> >On 01 Jan, no...@audiomisc.co.uk wrote:
> >> > Why does it matter with street lights? No-one (effectively)
complained
> >> > about the (bluish) mercury lights or even low (yellow) and
high (pink)
> >> > pressure sodium lights.
> >
> >> Afraid I can't now recall the reasons given. I'll see if I can
find my
> >> copy of that issue of 'Spectrum', although I tend to bin them
afer a few
> >> months so this will be a matter of luck. Alteratively, the
article may
> >> be on their website.
> >
> >Found it. Issue 10.16 of IEEE Spectrum "The early adopter blues"
by Jeff
> >Hecht. Not re-read it, but you may be able to find the details on
the web.
>
http://spectrum.ieee.org/green-tech/conservation/led-streetlights-are-g
iving-neighborhoods-the-blues
What moaning minnies. I've got two metres of RGB LED strip over my
living room window hooked up to a three knob dimmer so I can have any
colour I like. Maybe they could have a similar arrangement for street
lighting, radio controlled so they can adjust the colour to suit
people's tastes.
--
Max Demian
charles
Jan 2, 2017, 3:41:42 PM1/2/17
to
In article <almarsoft.6879...@news.plus.net>,
or even adjust it yourself from your phone as you walk past.
--
from KT24 in Surrey, England
--
from KT24 in Surrey, England
Scott
Jan 3, 2017, 6:01:31 AM1/3/17
to
0 new messages