On Thu, 17 Nov 2016 17:13:52 +0000, The Natural Philosopher wrote:

On 17/11/16 15:43, Johnny B Good wrote:
"Luminary" is just the 'posh' or 'technical' term for any light fitting,
commonly used by the authors of technical publications relating to lamps
and lighting.

No, actually it isn't,

That is a luminaire. French for a light fitting complete.

Thank you TNP. I'd just got to the point where I couldn't stand the thought
of yet more dignitaries around my house just hold lamps, so you saved me
from pointing out the difference.

A luminary is a person or occasionally a natural object like the sun or
moon, that enlightens or gives off light.

In UK.D-i-y *I* am a luminary.

OK.
--
Peter.
The gods will stay away
whilst religions hold sway

On 17/11/2016 15:43, Johnny B Good wrote:

If the "Famous Clive" can be persuaded to sample such lamps from
Poundland and Morrisons, et all for a really in depth analysis (usually
to the point of destruction), we'd all be guaranteed a definitive
answer. :-) It might be worth checking out his more recent YT videos for
such a product comparison. You never know, he may already have done the
work for us.



Unfortunately the LED bulbs sold in pound shops or even a well known
food outlet are likely to be a different manufacturer next week.
'Branded' LEDs are likely to be more consistent in their performance BUT
they will be a lot more expensive and may not perform any better than
the best of the pound offerings.

My experience with LEDs is that 5/6 years ago many led bulbs I purchased
failed - mainly getting much dimmer. In the past 2/3 years LEDs I've
purchased (branded and cheap non-branded) have been very reliable.
However I now only have 4 bulbs in fittings with restricted ventilation.
I have replaced 4 fittings with panel type LED lights and other LED
bulbs are in fairly open fittings.

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

On Thu, 17 Nov 2016 17:13:52 +0000, The Natural Philosopher wrote:

On 17/11/16 15:43, Johnny B Good wrote:
"Luminary" is just the 'posh' or 'technical' term for any light
fitting,
commonly used by the authors of technical publications relating to
lamps and lighting.

No, actually it isn't,

That is a luminaire. French for a light fitting complete.

A luminary is a person or occasionally a natural object like the sun or
moon, that enlightens or gives off light.

In UK.D-i-y *I* am a luminary.

Yes, I already corrected him once but he didn't notice!


--
My posts are my copyright and if @diy_forums or Home Owners' Hub
wish to copy them they can pay me £1 a message.
Use the BIG mirror service in the UK: http://www.mirrorservice.org
*lightning surge protection* - a w_tom conductor

On Thu, 17 Nov 2016 15:56:03 +0000, Dave Plowman (News) wrote:

In article ,
Johnny B Good wrote:
"Luminary" is just the 'posh' or 'technical' term for any light
fitting, commonly used by the authors of technical publications
relating to lamps and lighting.

Don't think so. A luminary is most commonly a famous person.

Luminaire is the term you'd find in text books.

And in the Wiring Regulations.



--
My posts are my copyright and if @diy_forums or Home Owners' Hub
wish to copy them they can pay me £1 a message.
Use the BIG mirror service in the UK: http://www.mirrorservice.org
*lightning surge protection* - a w_tom conductor

On Thu, 17 Nov 2016 15:56:03 +0000, Dave Plowman (News) wrote:

In article ,
Johnny B Good wrote:
"Luminary" is just the 'posh' or 'technical' term for any light
fitting, commonly used by the authors of technical publications
relating to lamps and lighting.

Don't think so. A luminary is most commonly a famous person.

Actually, not necessarily 'famous' so much as a person held up by their
peers as "A Leading Light" in their field of study or expertise.


Luminaire is the term you'd find in text books.

I checked this out a few months ago because that was also my
recollection (I just wanted to be sure of the spelling). However, I seem
to have gotten turned around to the use of "Luminary" for some
inexplicable reason (possibly a case of 'over-thinking it' and the
'double bluff' effect coming into play. :-(

Anyhow, wherever I've used the word 'luminary' in the context of lamps
and lighting, I've obviously intended the word 'luminaire'. My apologies
for the irritation this must cause (on a par with misuse of the
apostrophe, confusing 'to' with 'too', 'loose' with 'lose', 'may be' for
'maybe' (and vice versa) and many more such faux pas too numerous to
mention in a usenet posting).

--
Johnny B Good

In article ,
Johnny B Good wrote:
On Thu, 17 Nov 2016 15:56:03 +0000, Dave Plowman (News) wrote:

In article ,
Johnny B Good wrote:
"Luminary" is just the 'posh' or 'technical' term for any light
fitting, commonly used by the authors of technical publications
relating to lamps and lighting.

Don't think so. A luminary is most commonly a famous person.

Actually, not necessarily 'famous' so much as a person held up by their
peers as "A Leading Light" in their field of study or expertise.

Yes. A legend in their own lunchtime.


Luminaire is the term you'd find in text books.

I checked this out a few months ago because that was also my
recollection (I just wanted to be sure of the spelling). However, I seem
to have gotten turned around to the use of "Luminary" for some
inexplicable reason (possibly a case of 'over-thinking it' and the
'double bluff' effect coming into play. :-(

Only reason I know it is because it was the generic term for all types of
TV lights. Each variety had an individual name too, of course.

Anyhow, wherever I've used the word 'luminary' in the context of lamps
and lighting, I've obviously intended the word 'luminaire'. My apologies
for the irritation this must cause (on a par with misuse of the
apostrophe, confusing 'to' with 'too', 'loose' with 'lose', 'may be' for
'maybe' (and vice versa) and many more such faux pas too numerous to
mention in a usenet posting).

It wouldn't be usenet if you didn't get half a dozen at least pointing out
this sort of thing while totally ignoring the point of the thread.

--
*A fool and his money can throw one hell of a party.

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

On 17/11/2016 17:13, The Natural Philosopher wrote:
On 17/11/16 15:43, Johnny B Good wrote:
"Luminary" is just the 'posh' or 'technical' term for any light fitting,
commonly used by the authors of technical publications relating to lamps
and lighting.

No, actually it isn't,

That is a luminaire. French for a light fitting complete.

A luminary is a person or occasionally a natural object like the sun or
moon, that enlightens or gives off light.

In UK.D-i-y *I* am a luminary.

ok, where shall we stick the bulb? ;-)



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Thu, 17 Nov 2016 08:50:44 -0800, whisky-dave wrote:

On Thursday, 17 November 2016 15:43:10 UTC, Johnny B Good wrote:
On Thu, 17 Nov 2016 03:17:34 -0800, whisky-dave wrote:

On Thursday, 17 November 2016 05:52:29 UTC, Johnny B Good wrote:
On Wed, 16 Nov 2016 05:32:28 -0800, whisky-dave wrote:

On Wednesday, 16 November 2016 10:49:56 UTC, Dave Plowman (News)
wrote:
In article ,
Johnny B Good wrote:
Yes - they are improving all the time. Which is odd since so
many thought them perfect when they first arrived. Difficult
to improve perfection. ;-)

But, according to a 2 1/2 year old announcement by Cree of
their record
breaking 303Lm/W laboratory samples, it looks like we're
currently only one third of the way there despite being 6
months overdue on the promised availability of such high
efficiency LED lamps in the retail stores. :-(

My rule of thumb is can I buy easily - ie in a local shed or
supermarket -
an LED which will replace a tungsten with no downsides and at an
affordable price.

that's why I walked almost 500 yards to B&Q .
My priority is that it fits the socket I intend to put it in.

Not forgetting the other priority that they don't overheat in the
luminary. :-)

I'm not the sort of person to insert them in such a place, I always
install my bulbs into bulb holders.

"Luminary" is just the 'posh' or 'technical' term for any light
fitting,
commonly used by the authors of technical publications relating to
lamps and lighting. I presume you're referring to a pendant lamp holder
hanging from a ceiling rose cord (naked or else fitted with a well
ventilated lamp shade of some sort).

or any other holder.

My apologies btw, for misusing 'luminary' in place of 'luminaire' (which
I've just added to Pan's spell check dictionary).

Some use the term voltage to describe something whereas here we can
also use the term potential difference, but go into shop and ask for a
battery of 9V potential difference.


If that presumption on my part is justified and you're considering
this
aspect of lamp usage on every occasion where you decide to fit a LED
lamp to replace a tungsten filament GLS lamp (or even a CFL), then
you're doing exactly the right thing.

yeah sorted.


Lamp holder or light fitting (or Luminary) wattage ratings were more
about how much heat they could cope with from an incandescent lamp than
about the lamp itself. With LED lamps, the wattage limit is a function
of how well a luminary can keep a LED lamp cool enough to achieve its
rated life (typically 15 to 30 thousand hours with the higher wattage
examples). There is no easy rule of thumb over de-rating a 60W fitting
down to say 20 or 25% when used with a LED lamp. Although such a de-
rating figure is a handy starting point, you still have to consider how
well the luminary is likely to perform in preventing unwanted heat
build up.

Well normally the heat comes from what's plugged into it.
At their base, LED lamps/bulbs (rather than LEDs) get hot to the touch.
very hot in fact.

That's very much affected by lamp orientation since most of the heat is
generated by the LEDs themselves. fitting a LED or CFL type of GLS lamp
'cap up' as in a typical pendant fitting will cause the cap to run hotter
simply because the half to one watt dissipation by the electronic ballast
components become reliant upon the warm air being convected from the
envelope to keep it cooled. The modest heat dissipation in the cap or
base of the lamp just raises the cap temperature until a new thermal
equilibrium is attained.

For a high quality lamp with a high efficiency electronic ballast using
high temperature long life components, this could well be the optimum
orientation despite reliance on a flow of warm to hot air to carry away
the heat produced by the losses in the ballast components. The key thing
here is to provide ample ventilation around the lamp. The less obstructed
and faster the flow, the lower its temperature will be and the more
effective it becomes (even at elevated temperatures) as a means of
cooling the lamp components due to the higher velocity of that airflow.




The higher the LED lamp efficiency, the less of an issue such heat
build
up becomes. When I invested a fiver in an Asda 5W 270Lm 'bargain lamp'
5 or 6 years ago, I'd intended it for the wall mounted bed head
luminaries to replace the overly bright 7W CFLs which had replaced the
25W tungsten filament BC22 candle lamps originally fitted.

These luminaries used small "Snowdrop" style glass shades which
offered
no through ventilation. Not a problem for the incandescent lamps they'd
been designed for (and not much of a problem for the 7W CFLs since they
protruded further out of the open end of the glass shade). However, I
realised that my 5 quid investment could land up cooking itself to an
early demise from the effect of inadequate ventilation.


Indeed, I got the impression (rightly or wrongly) that the light
output
was reduced after being lit for more than 15 to 20 minutes suggesting
that the LEDs were operating uncomfortably close to their upper
temperature limit. Discretion being the better part of valour, I landed
up relegating this "Asda Special" to a ceiling mounted batten socket at
the foot of our basement stairs where it has been in service ever since
without (as one might expect of an open unshaded lamp holder in a lower
than usual temperature environment) any signs of impending failure.

My LEDs lamps and bulbs are mostly used with dimmers (trailing edge)
they are usually dimmed by at least 50% ('measured by rotation of the
pot)
I believe this may help with reducing the heat they do produce.


A couple of months ago, I spotted 5W 325Lm BC22 candle lamps in
Poundland
and decided it was worth a punt to trial one in one of those bedroom
wall light fittings. The results, compared to the more expensive 270Lm
"Asda Bargain", were a lot more encouraging so I bought a second lamp
to complete the upgrade.

you devil


After a few weeks of trouble free service, I felt confident enough to
invest another 7 quid on SES versions to upgrade the lighting in the
living room (2 wall luminaries and a 5 lamp chandelier), followed a
fortnight later with an upgrade to the similar 5 lamp chandelier in the
lounge which, after about a week or two's service, suffered a lamp
failure.

I'm replacing the majority of my none LEDs light with LEDs as the
tungsten and halagen blow.



One random infant mortality failure out of 14 LED lamps bought in our
local "Pound Shop" seemed pretty good going imo,

It does.

especially since you
never get any arguments when returning faulty items for refund or
replacement in the Poundland or Poundworld stores.

I've never tried. I avoid these places. I only have an hour lunch break.



In terms of appearance, apart from the "whiter light", they perform
just
as well as the traditional pearl enveloped tungsten filament lamps
they've replaced. With a 15,000 hour rating, these lamps would seem to
be much better value for their money than a traditional tungsten
filament lamp costing around 25 to 33 pence each when bought in packs
of 4 or 3 in a pound shop.

Of course, only time will tell whether the promised 15,000 hour
average
lifetime is a realisable target or simply just 'hype'.

Is there any info on how long they can be kept on for ?

Unlike that 30W CFL, there's no mention of such a caveat in relation to
a warranty. In fact, there's no warranty period mentioned at all other
than the 15000 hours average lifetime and a switching cycles rating of
10000 times along with a promise to replace or refund if not satisfied
with the lamp's quality along with the caveat "This does not affect your
statutory rights." The packaging shows the brand name as "Electrek" with
a UK address (post box number in the Birmingham post code area).
Undoubtedly, this is an import company rather than an actual manufacturer
(unless they're claiming to be a manufacturer which just happens to
outsource every aspect of production to other more specialised
manufacturers).



Where they've been
installed in low usage locations (bedroom reading lamps or the very
rarely used 5 lamp chandelier in the living room and that basement
location) it could quite easily take several years of use before
they've even clocked up their first thousand hour's worth of run time.

true if age is the only criteria for them blowing.

That 2.7 hours a day caveat on the 6 year warranty with that 6000hour
rated 30W CFL I mentioned earlier, was simply to indicate that even in
very low usage cases, it would be covered by that untypically extended
warranty.



The living room wall lights are the most likely to give any indication
of actual versus promised life time performance figures over a
reasonable timescale. At just a pound each lamp, that's not too great
an investment to run 'The Experiment' to prove or disprove the life
time rating claims made for these lamps.

I'd like to see you're 'blind' study

I'd rather doubt I'd be around long enough to see the end of such a
study. Life's just too short for that sort of indulgence. :-(


if I had the space and time I'd put one on and leave it on 24/7/365.


and another I'd leave on for 12 hours a day, both should last the same
length of time when on. So the 12 hour day one should last twice as long
as the 24 hour a day one.

Unless they incorporate a suicide countdown timer circuit, you'd
probably have to use ten times as many lamps to get a more meaningful
statistical finding.

If you're going to go to that much trouble, you might as well take
measurements of their light output on a regular basis, say every 500
hours of run time, whilst you're at it (and, for completeness, measure
their operating temperatures against room temperature). :-)



Morrisons are selling LED lamps that appear to have come off the same
factory production line as the Poundland ones but at just over 4 times
the price! I think it is a similar story in Asda, Aldi and Lidl stores.
Just for once, it seems Poundland are offering a product at a genuinely
bargain price. They say you get what you pay for ...

You can get a slap if you say that to the wrong person

but I'd be very
surprised if this turned out to be the case for those Poundland lamps.

If the "Famous Clive" can be persuaded to sample such lamps from
Poundland and Morrisons, et all for a really in depth analysis (usually
to the point of destruction), we'd all be guaranteed a definitive
answer. :-) It might be worth checking out his more recent YT videos
for such a product comparison.

I did watch one but he said the 'bulbs' are no longer available in the
UK.

You never know, he may already have done the
work for us.

I doubt he's had a LED lamp or bulb on for the past 5-15 years. His
don't last much longer than his videos ;-)

Ah well, he does seem to insist on testing these things to destruction
so that's just to be expected. :-)

I rather like his "scientific" approach to analysing such product. When
you think about it, he's using exactly the same approach as the
physicists working with the LHC at CERN. I don't suppose you could get
much more 'scientific' than that. :-)

--
Johnny B Good

On Fri, 18 Nov 2016 01:08:30 +0000, John Rumm wrote:

On 17/11/2016 17:13, The Natural Philosopher wrote:
On 17/11/16 15:43, Johnny B Good wrote:
"Luminary" is just the 'posh' or 'technical' term for any light fitting,
commonly used by the authors of technical publications relating to lamps
and lighting.

No, actually it isn't,

That is a luminaire. French for a light fitting complete.

A luminary is a person or occasionally a natural object like the sun or
moon, that enlightens or gives off light.

In UK.D-i-y *I* am a luminary.

ok, where shall we stick the bulb? ;-)

Somewhere that needs illumination, i.e. lacks sunlight.
--
Peter.
The gods will stay away
whilst religions hold sway

On 17/11/16 23:52, Johnny B Good wrote:
many more such faux pas too numerous to
mention in a usenet posting).

No faux pas are too numerous to mention in a Usenet posting.


--
If I had all the money I've spent on drink...
...I'd spend it on drink.

Sir Henry (at Rawlinson's End)

On Fri, 18 Nov 2016 08:25:44 +0000, PeterC wrote:

On Fri, 18 Nov 2016 01:08:30 +0000, John Rumm wrote:

On 17/11/2016 17:13, The Natural Philosopher wrote:
On 17/11/16 15:43, Johnny B Good wrote:
"Luminary" is just the 'posh' or 'technical' term for any light
fitting,
commonly used by the authors of technical publications relating to
lamps and lighting.

No, actually it isn't,

That is a luminaire. French for a light fitting complete.

A luminary is a person or occasionally a natural object like the sun
or moon, that enlightens or gives off light.

In UK.D-i-y *I* am a luminary.

ok, where shall we stick the bulb? ;-)

Somewhere that needs illumination, i.e. lacks sunlight.

I had an image of "Uncle Fester" pop into my mind when I saw that
question. :-)

--
Johnny B Good

On 16/11/2016 18:05, charles wrote:


It's always possible that Phillips are using these high output LEDs in
their theatric division rather then their domestic one. In that areea
forced cooling, by means of a fan, isn't uncommon.


or street lighting where a small physical size of the fitting isn't
important.

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