Tim Streater wrote
Tim Watts wrote

And in the old days, we mostly only had BC fittings to worry about...

Yes, what is it with this screw-in **** that seems to be creeping in?

Its basically a better design.

In article om,
"dennis@home" writes:


"Andrew Gabriel" wrote in message
...

8

Not true for Standard filament lamps - don't confuse the tendancy
to die at switch-on with a reduction in lamp life due to switching;
there is virtually none and it's a common misconception. What happens
is that for the last ~5 or so hours of life, the lamp won't survive
a switch-on, so if it's on for less than 5 hours at a time, its
end-of-life failure will be at a switch-on.

Thermal shock each time you switch the lamp on will reduce its life.

How?
A thin tungsten wire is about as resistant to thermal shock
as anything you can think of. No other parts of a filament
lamp normally contribute to standard lamp failures, even in
lamps which are flashed on and off all their life.*

In any case, folks who operate lamps which are flashed all
their life have plenty of data to show life is related to the
total "on" time, and not the number of times switched, so
it's kind of pointless to speculate on the mechanism behind
a failure method that doesn't exist.

*Again, I'm excluding halogen lamps here, which have other
possible failure modes.

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

In article ,
Tim Watts writes:
Lieutenant Scott wrote:
I've not seen the point in low voltage lighting
at all, all you're doing is adding the requirement for a transformer and
more wiring.

Good for certain installation zones which is why I have one (shower). I
would also use it for soffit lighting if I had any as that's the one other
place it's likely to get a good soaking.

I have built my own LED soffit lights, because:
a) the lamps would be difficult to change, requiring access to neighbours'
gardens to foot the ladder (as I did for fitting, but that's a one-off).
I'm running 3W LEDs at 2W on substantial heatsinks, so should get much
longer than the rated life (I'm not expecting to ever change them).
b) The small LED light source enabled me to use optics to direct the
light precisely along the path, without spilling/wasting it where it's
not wanted (e.g. into neighbour's windows).
c) Much cheaper than buying any of comperable quality, even if I could
find some which generated the right beam pattern.

If they ever got water into them, they would be destroyed - that
wasn't a reason I used LEDs.

I have also recently designed/built an outdoor LED lamp for someone
else's garden, which generates a very specific light pattern to light
up a path at night. The motivation for this was to avoid putting mains
wiring around the garden (it runs off 24V). The unit is a conventional
PIR lantern bought from B&Q, gutted and fitted with multiple LEDs and
optics to direct the beam, and internal copper mountings to conduct
the heat to the aluminium case and hold the LEDs at precisely the right
angles to generate the required light pattern. The location is right
next to a road junction, and another factor was to avoid any dazzle
outside the garden - the precise control of light which can be
achieved with small light source LEDs means the light source is
invisible from the road. A neighbour described it as ghostly, because
you can see a brightly lit path when it's on, but the quantity of light
required to do that doesn't seem to come from the lantern, which means
I'm not wasting the light dazzling peoples' eyes. It's working very
well, and I will shortly be designing another one for a different
location and lighting pattern.

Then there's various fluorescent fittings T4,T5,PLS,PLC,PLT, 2D 2pin, 2D
4pin, GX53

It's mad...

When designing fittings, I try to consider which ones are likely to
still be around in 10-20 years time. I like and have used 2D lamps
in a number of designs, but they don't meet the efficiency standards
required by the EU. However, it looks like manufacturers are now
addressing this with modifications to some of the 2D power ratings,
but other ratings will probably go away.

I try to avoid those ones. I don't want to be stuck with fluorescent.

I'm using a few 2D commercial fittings (simple, white, round, not too big)
for the kids bedrooms and the hall. The bedroom deployment is a separate
circuit to give a good strong daylight effect over a desk as both rooms are
north facing.

I figure an all white fitting with a white diffuser will tend to go
unnoticed against a white ceiling - I'll see how right I am - but I'm not
too bothered as this is a clear "function over form" scenario. Their "main"
lighting is chrome, dimmable, and SWMBO approved.


It's occured to me that for a few places I said I wanted downlighters with
LEDs for nightlighting or to sort out dark corners, I don't necessarily need
true downlighters. I actually don't really like them anyway - I've just got
programmed into defaulting to them because everyone else does.

Well I don't.
Downlighters do have their place, but when I see them being used to
provide general lighting, I just see "cheap and nasty", poor lighting
design, and no imagination.

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

"Andrew Gabriel" wrote in message
...
In article om,
"dennis@home" writes:


"Andrew Gabriel" wrote in message
...

8

Not true for Standard filament lamps - don't confuse the tendancy
to die at switch-on with a reduction in lamp life due to switching;
there is virtually none and it's a common misconception. What happens
is that for the last ~5 or so hours of life, the lamp won't survive
a switch-on, so if it's on for less than 5 hours at a time, its
end-of-life failure will be at a switch-on.

Thermal shock each time you switch the lamp on will reduce its life.

How?
A thin tungsten wire is about as resistant to thermal shock
as anything you can think of. No other parts of a filament
lamp normally contribute to standard lamp failures, even in
lamps which are flashed on and off all their life.*

From the lighting industry federation web site

"Q. Is a GLS lamp life affected by switching rate?

A. Life is tested with one switching per 12 hours. One switching per hour
reduces life about 1%."



In any case, folks who operate lamps which are flashed all
their life have plenty of data to show life is related to the
total "on" time, and not the number of times switched, so
it's kind of pointless to speculate on the mechanism behind
a failure method that doesn't exist.

If you design a lamp that flashes all the time you either under run the lamp
or you use soft start circuits.
This extends the life a lot.
You may or may not have noticed that traffic lights use soft start to
improve lamp life.


*Again, I'm excluding halogen lamps here, which have other
possible failure modes.

Well you wouldn't want a halogen lamp to run below its minimum envelope temp
or it would blacken.

Andrew Gabriel wrote:


I have built my own LED soffit lights, because:
a) the lamps would be difficult to change, requiring access to neighbours'
gardens to foot the ladder (as I did for fitting, but that's a one-off).
I'm running 3W LEDs at 2W on substantial heatsinks, so should get much
longer than the rated life (I'm not expecting to ever change them).
b) The small LED light source enabled me to use optics to direct the
light precisely along the path, without spilling/wasting it where it's
not wanted (e.g. into neighbour's windows).
c) Much cheaper than buying any of comperable quality, even if I could
find some which generated the right beam pattern.

If they ever got water into them, they would be destroyed - that
wasn't a reason I used LEDs.

I have also recently designed/built an outdoor LED lamp for someone
else's garden, which generates a very specific light pattern to light
up a path at night. The motivation for this was to avoid putting mains
wiring around the garden (it runs off 24V). The unit is a conventional
PIR lantern bought from B&Q, gutted and fitted with multiple LEDs and
optics to direct the beam, and internal copper mountings to conduct
the heat to the aluminium case and hold the LEDs at precisely the right
angles to generate the required light pattern. The location is right
next to a road junction, and another factor was to avoid any dazzle
outside the garden - the precise control of light which can be
achieved with small light source LEDs means the light source is
invisible from the road. A neighbour described it as ghostly, because
you can see a brightly lit path when it's on, but the quantity of light
required to do that doesn't seem to come from the lantern, which means
I'm not wasting the light dazzling peoples' eyes. It's working very
well, and I will shortly be designing another one for a different
location and lighting pattern.


Nice... Where do you get the optics?


When designing fittings, I try to consider which ones are likely to
still be around in 10-20 years time. I like and have used 2D lamps
in a number of designs, but they don't meet the efficiency standards
required by the EU. However, it looks like manufacturers are now
addressing this with modifications to some of the 2D power ratings,
but other ratings will probably go away.

Is there any opinion on whether 28W will be a safe bet, or not?

--
Tim Watts

On Sun, 04 Mar 2012 19:44:24 -0000, Rod Speed wrote:

Tim Watts wrote
Lieutenant Scott wrote
My kitchen has ES fittings (they were there when I moved in),
but I bought some ES to BC adapters for a quid each so I can
use up the free CFLs the energy companies keep giving me.

Ours give you a choice, you can have either.

Same here, but I get all my neighbours ones too as they don't want them.

--
http://petersparrots.com
http://petersphotos.com

It's strange, isn't it? You stand in the middle of a library and go "Aaaaaaagghhhh!!!!" and everyone just stares at you. But you do the same thing on an aeroplane, and everyone joins in.

On Mon, 5 Mar 2012 07:28:38 +1100, Rod Speed wrote:

12V halogens are at least twice as efficient as mains halogens.

Sure, but you have to allow for the lousy efficiency that
the transformer produces too when used in a house.

Except that gert lumps of iron wrapped in copper aren't that comon
any longer. The "transformers" are small SMPS's, less problems with
people swapping out bulbs with different ratings than what the system
was designed for or problems when a bulb has blown and isn't quickly
replaced.

--
Cheers
Dave.

Rod Speed wrote:

Tim Streater wrote
Tim Watts wrote

And in the old days, we mostly only had BC fittings to worry about...

Yes, what is it with this screw-in **** that seems to be creeping in?

Its basically a better design.

Unless you have metal casing forming the main socket screw thread, and you
use it in a country where polarity is not guaranteed - eg touching the lamp
neck (eg whilst unscrewing) gives you a shock.

Of course, modern designs use an insulating thread and a contact near the
base - but BC have never had this problem.

Occasionally, I have found ES resistant to unscrewing resulting in shearing
the bulb base.

--
Tim Watts

On Sun, 04 Mar 2012 20:28:38 -0000, Rod Speed wrote:

Andrew Gabriel wrote
Lieutenant Scott wrote

Do you mean low voltage? I've not seen the point in
low voltage lighting at all, all you're doing is adding the
requirement for a transformer and more wiring.

12V halogens are at least twice as efficient as mains halogens.

Sure, but you have to allow for the lousy efficiency that
the transformer produces too when used in a house.

I came across someone running 15 30W halogens off an electronic transformer designed for 5. For some reason it tried. Sometimes they would be dim, sometimes they would flicker madly. He also used a dimmer switch for them which he managed to melt. I couldn't find him a dimmer switch that would take so much load, so I wired in two of them. The circuit breaker was also humming very loudly and got quite warm when he overloaded the transformer, it must have been drawing a very weird uneven current.

--
http://petersparrots.com
http://petersphotos.com

Confuscious say: "Man who sit on tack get point!"

Dave Liquorice wrote
Rod Speed wrote

12V halogens are at least twice as efficient as mains halogens.

Sure, but you have to allow for the lousy efficiency that
the transformer produces too when used in a house.

Except that gert lumps of iron wrapped in copper aren't that comon
any longer. The "transformers" are small SMPS's, less problems with
people swapping out bulbs with different ratings than what the system
was designed for or problems when a bulb has blown and isn't quickly
replaced.

And more problems with them failing.

Tim Watts wrote
Rod Speed wrote
Tim Streater wrote
Tim Watts wrote

And in the old days, we mostly only had BC fittings to worry about...

Yes, what is it with this screw-in **** that seems to be creeping in?

Its basically a better design.

Unless you have metal casing forming the main socket screw thread,
and you use it in a country where polarity is not guaranteed - eg
touching the lamp neck (eg whilst unscrewing) gives you a shock.

Of course, modern designs use an insulating thread and a
contact near the base - but BC have never had this problem.

Occasionally, I have found ES resistant to unscrewing resulting in shearing the bulb base.

Sure, but you can get that with baynet sockets too.

And they have the other problem, they are less mechanically solid too.

In article ,
Tim Watts writes:

Nice... Where do you get the optics?

Rapid sell a selection, and CPC a few.
Mostly I have bought them from trade lighting shows (or
got free samples in some cases).

Farnell were advertising heavily at the last one I went to,
but I haven't yet got around to looking at what they have.
Thermal management (heatsink, and heat conduction) is even
more critical. Rapid stopped selling the heatsinks I often
use, so I will have to find another source shortly. The
other way, as above, is to conduct the heat away to the
luminare casing, particularly if it's aluminium or copper.
I tend to make copper strips to do this out of copper pipe
hammered flat. I did use some copper bus bar offcuts too,
but buying it new is much more expensive than using copper
pipe.

When designing fittings, I try to consider which ones are likely to
still be around in 10-20 years time. I like and have used 2D lamps
in a number of designs, but they don't meet the efficiency standards
required by the EU. However, it looks like manufacturers are now
addressing this with modifications to some of the 2D power ratings,
but other ratings will probably go away.

Is there any opinion on whether 28W will be a safe bet, or not?

16W and 28W look safe - GE have produced wattmizer versions.
10W and 21W don't look like they have a future, and I have used
both of these. I wouldn't use 10W nowadays in new designs as that's
right in ideal LED terratory now. Getting same light output as a
21W lamp in the same space and keeping it cool enough for LEDs is
still quite a challenge. (28W would be easier as the lamp is bigger,
and so will the fitting be - indeed LED versions of former 2D lights
already exist in the larger sizes.)

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

In article ,
Tim Watts writes:
Rod Speed wrote:

Tim Streater wrote
Tim Watts wrote

And in the old days, we mostly only had BC fittings to worry about...

Yes, what is it with this screw-in **** that seems to be creeping in?

Its basically a better design.

Unless you have metal casing forming the main socket screw thread, and you
use it in a country where polarity is not guaranteed - eg touching the lamp
neck (eg whilst unscrewing) gives you a shock.

This results in some electrocutions (IIRC, about 2 in the US per year).
No one has managed to find any record of an electrocution from a BC
lampholder by touching the exposed live pins - you probably can't get
a good enough contact even with wet hands.

Of course, modern designs use an insulating thread and a contact near the
base - but BC have never had this problem.

Occasionally, I have found ES resistant to unscrewing resulting in shearing
the bulb base.

Another common problem with US ones is the whole holder unscrewing
and either coming apart, or jaming because the two part lampholder
has a finer screwthread than the lamp base thread. The EU 40mm
mounting ones seem much less prone to this (many have a ratchet
which prevents the lampholder parts ever being unscrewed).

ES grips the lamp better which means it can support heavier lamps
at strange angles, which the pin springs in a BC holder can't.
This was a problem with the first CFLs with iron ballasts, but
it's not a problem with most current lamps which are much lighter.

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

Andrew Gabriel wrote
Tim Watts wrote
Rod Speed wrote
Tim Streater wrote
Tim Watts wrote

And in the old days, we mostly only had BC fittings to worry about...

Yes, what is it with this screw-in **** that seems to be creeping in?

Its basically a better design.

Unless you have metal casing forming the main socket screw thread,
and you use it in a country where polarity is not guaranteed - eg
touching the lamp neck (eg whilst unscrewing) gives you a shock.

This results in some electrocutions (IIRC, about 2 in the US per
year). No one has managed to find any record of an electrocution
from a BC lampholder by touching the exposed live pins - you
probably can't get a good enough contact even with wet hands.

Of course, modern designs use an insulating thread and a
contact near the base - but BC have never had this problem.

Occasionally, I have found ES resistant to unscrewing resulting in
shearing the bulb base.

Another common problem with US ones is the whole holder unscrewing
and either coming apart, or jaming because the two part lampholder
has a finer screwthread than the lamp base thread. The EU 40mm
mounting ones seem much less prone to this (many have a ratchet
which prevents the lampholder parts ever being unscrewed).

ES grips the lamp better which means it can support heavier lamps
at strange angles, which the pin springs in a BC holder can't.

And all you have to do to eliminate the electrocution problem is to ensure
that the outer only ever gets connected to the neutral, not the active.

This was a problem with the first CFLs with iron ballasts, but
it's not a problem with most current lamps which are much lighter.

The big PAR38s ares still around and quite commonly used in domestic situations.

Still plenty with the heavy glass too.

Rod Speed wrote:


And all you have to do to eliminate the electrocution problem is to ensure
that the outer only ever gets connected to the neutral, not the active.

Yes - but that will never happen in many countries. Even in the UK, where
polarity is (or should be by regulation) assured, and wiring the phase to
the centre pin on an ES fitting is mandatory - you will still get polarity
cock ups.

Case in point - my son got a bit of a belt from such a fitting in China. I
do not believe they maintain polarity, and RCDs are a relatively new
idea[1]. Lucky he was standing on the bed and possibly leaning against the
wall as opposed to holding onto a water pipe.

[1] though to be fair to the Chinese, last time I had a quick shufty around
a new build flat, the CU was stuffed full of RCBOs and put a typical British
board to shame - I really have no idea if that is mandator or if the owner
had just paid a lot to a top notch sparky - but given their liking of
electrode heater shower units plugged into sockets near (or in!) the shower,
I bloody hope it is required now.

The actual answer is as I mentioned before, to use an insulating thread with
the outer contact near the bottom so the bulb shell cannot become live until
more or less fully screwed in - it's about the only fully idiot proof
method.

Even BC holders, which as Andrew mentioned have a surprisingly low injury
rate, modern *decent* ones only make the contacts live upon insertion of the
bulb (Hager-Ashley)[1] - but this is not a requiremnet

The Ashley ones do this by rotating a plastic shim using the side prongs
during the insertion twist - which is hard to accidently defeat.

This was a problem with the first CFLs with iron ballasts, but
it's not a problem with most current lamps which are much lighter.

The big PAR38s ares still around and quite commonly used in domestic
situations.

Still plenty with the heavy glass too.
--
Tim Watts

On 4 Mar,
Tim Watts wrote:


What?? I have never seen a heat damaged lamp socket.

I have never (yet) seen one when using CFLs or LEDs. I must have seen
hundreds over the years when using incandescents, usually of 100 watt or
more.

You are either young or blinkered if you haven't come across any.

--
B Thumbs
Change lycos to yahoo to reply

On 4 Mar,
Tim Streater wrote:

In article o.uk,
"Dave Liquorice" wrote:

On Sun, 04 Mar 2012 13:43:46 +0000, Tim Watts wrote:
{snip}
What?? I have never seen a heat damaged lamp socket.

Good grief how have you managed to avoid that? Never used tungsten
bulbs?

Daughters beside lamp failed the other night, the "bakerlite" lugs
for the bayonet had just broken, weakened by the heat.

But it shouldn't just be the bakelite, Shirley? That covers up a brass
bit that you actually plug the lamp into.

Which is rather thin and bends quite easily allowing the bulb to fall.__

--
B Thumbs
Change lycos to yahoo to reply

In article ,
"Rod Speed" writes:
Andrew Gabriel wrote
This results in some electrocutions (IIRC, about 2 in the US per
year). No one has managed to find any record of an electrocution
from a BC lampholder by touching the exposed live pins - you
probably can't get a good enough contact even with wet hands.

Of course, modern designs use an insulating thread and a
contact near the base - but BC have never had this problem.

Occasionally, I have found ES resistant to unscrewing resulting in
shearing the bulb base.

Another common problem with US ones is the whole holder unscrewing
and either coming apart, or jaming because the two part lampholder
has a finer screwthread than the lamp base thread. The EU 40mm
mounting ones seem much less prone to this (many have a ratchet
which prevents the lampholder parts ever being unscrewed).

ES grips the lamp better which means it can support heavier lamps
at strange angles, which the pin springs in a BC holder can't.

And all you have to do to eliminate the electrocution problem is to ensure
that the outer only ever gets connected to the neutral, not the active.

Won't ever happen - most countries don't preserve polarity,
and in some cases, neither main conductor is a neutral (at
or near ground potential).

This was a problem with the first CFLs with iron ballasts, but
it's not a problem with most current lamps which are much lighter.

The big PAR38s ares still around and quite commonly used in domestic situations.

Still plenty with the heavy glass too.

I was thinking of GLS and retrofit replacements.
If you go to spot/flood lamps, even R80 and R63 are always screws,
to hold them firmly.

The one that makes me smile is that the low pressure sodium (SOX)
lamps the world over are all BC. The 180W one is almost 4 foot long
and single ended and must be run horizontally. Of course, the BC
doesn't fully support the lamp - a wire loop is used too - but it
does ensure correct rotational orienation in the lantern.

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

On 3/4/2012 3:23 PM, Rod Speed wrote:
S Viemeister wrote
Tim Watts wrote
Lieutenant Scott wrote

Filaments use a fortune in electricity and are very hot so tend to damage the light socket.

What?? I have never seen a heat damaged lamp socket.

I have. Three pendant sockets - they were like that when we moved in.
But I suspect the previous owner had used heat lamps in them.

You dont have to use heat lamps in them, just have them vertical
and have high power bulbs in them, and low quality bakelite sockets.

I suspected the heat lamps on two, because there _was_ a heat lamp in
the third one...

There is a reason you can buy ceramic sockets, particularly in ES format.

Tim Watts wrote
Rod Speed wrote

And all you have to do to eliminate the electrocution problem is to ensure
that the outer only ever gets connected to the neutral, not the active.

Yes - but that will never happen in many countries.

Sure, but it doesnt really make a lot of sense to be deciding what to
use in first world countrys based on what happens in the third world.

Cant see thats a problem in the first and most of the second world
and with the mandating of RCDs in so many of them now, electrocution
that way is likely to become even less of a problem than it currently is,
and the current level is really right down in the noise level now.

Even in the third world, a much bigger problem is
likely to be with deliberate theft of power instead
and stupid people riding on train roofs etc.

Even in the UK, where polarity is (or should be by regulation)
assured, and wiring the phase to the centre pin on an ES
fitting is mandatory - you will still get polarity cock ups.

Sure, but how many actually result in electocutions with US sockets ?

Bugger all basically.

Case in point - my son got a bit of a belt from such a fitting in China.

Sure, but thats life in the third world, you need to take more care
in those just like you need to take more care about malaria etc too
and even just food poisoning. It doesnt make any sense to be banning
ES sockets because of what might happen in a third world country.

I do not believe they maintain polarity, and RCDs are a relatively
new idea[1]. Lucky he was standing on the bed and possibly
leaning against the wall as opposed to holding onto a water pipe.

Yebbut, thats closer to the risk of taking a drink from the Ganges
with all those corpses they toss in there and with so many of
them ****ting on the ground anywhere they feel like it.

[1] though to be fair to the Chinese, last time I had a quick shufty
around a new build flat, the CU was stuffed full of RCBOs and put
a typical British board to shame - I really have no idea if that is
mandator or if the owner had just paid a lot to a top notch sparky -
but given their liking of electrode heater shower units plugged into
sockets near (or in!) the shower, I bloody hope it is required now.

The actual answer is as I mentioned before, to use an insulating
thread with the outer contact near the bottom so the bulb shell
cannot become live until more or less fully screwed in - it's about
the only fully idiot proof method.

Sure, but you dont see that done very often.

Even BC holders, which as Andrew mentioned have a surprisingly low
injury rate, modern *decent* ones only make the contacts live upon
insertion of the bulb (Hager-Ashley)[1] - but this is not a requiremnet

The Ashley ones do this by rotating a plastic shim using the side
prongs during the insertion twist - which is hard to accidently defeat.

Have you seen that much on stuff from china ?

This was a problem with the first CFLs with iron ballasts, but
it's not a problem with most current lamps which are much lighter.

The big PAR38s are still around and quite commonly used in domestic situations.

Still plenty with the heavy glass too.

In article ,
"Rod Speed" writes:
Tim Watts wrote
Rod Speed wrote

And all you have to do to eliminate the electrocution problem is to ensure
that the outer only ever gets connected to the neutral, not the active.

Yes - but that will never happen in many countries.

Sure, but it doesnt really make a lot of sense to be deciding what to
use in first world countrys based on what happens in the third world.

Cant see thats a problem in the first and most of the second world

Most of first and most of the second world has unpolarised
supplies by the time you get to an appliance (particularly a
low power one such as a light). The UK is in a minority in
preserving polarity through all our wiring systems right to
the appliance.

The actual answer is as I mentioned before, to use an insulating
thread with the outer contact near the bottom so the bulb shell
cannot become live until more or less fully screwed in - it's about
the only fully idiot proof method.

Sure, but you dont see that done very often.

It would also need the equivalent of the HO (Home Office) shirt
on the lampholder, to stop you gripping the lamp by the base.

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

On Sun, 04 Mar 2012 17:16:37 +0000, Tim Watts wrote:

PeterC wrote:

On Sun, 4 Mar 2012 11:20:42 +0000, Alan wrote:

In message , Tim Watts
wrote

I have had consistently good results from Prolite spirals over the last 3
years.

My experience with that brand
http://www.admac.myzen.co.uk/bulb/

My experience with 'daylight' Prolite: buzzed, stank and poor output. Got
a full refund OK.
Pity really, as they were what I was after according to the blurb.

It's really weird as I've had about 15 of them for building site lighting,
all 25-30W BC. One DoA (replaced), 3 got broken, and about 4-5 have died of
natural causes after something like 2+years permanantly on - of those that
died, I think 2 actually died and the rest were dimming and going brown/grey
so they got canned.

I get mine from Lampspecs - not that that should make any difference, unless
there are fakes kicking around.

My impression of Prolite is that they're intrisically fakes.

I've had GE branded CFLs which have been ****e - but the worst brand which
turned out not to be worth a spit was "Your" or "You" of something like that
(some chinese brand).

I saw advice, years ago, to use only the well-known brands and those
included GE - oh well...
--
Peter.
The gods will stay away
whilst religions hold sway

Rod Speed wrote:


Have you seen that much on stuff from china ?

Yes.

--
Tim Watts

On Sun, 04 Mar 2012 17:45:45 +0000, Tim Streater wrote:

Daughters beside lamp failed the other night, the "bakerlite" lugs
for the bayonet had just broken, weakened by the heat.

But it shouldn't just be the bakelite, Shirley? That covers up a brass
bit that you actually plug the lamp into.

Don't call me Shirley. B-)

No brass or other metal just plastic. Marked BS EN 61184. TBH I was
surprised that there wasn't any metal, not surprised it had failed.

--
Cheers
Dave.

On 04/03/2012 08:39, NT wrote:

3. I dont see any reason to resent the fact that some fail early, some
last longer than rated. Its how all types of bulb work.


It is because of the cost compared to traditional bulbs which are less
than a pound each. Would you accept the same argument for other consumer
goods? If a TV is expected to last seven years and some last fifteen
would be be upset if the one you bought only lasted six months? What
about a new car?

On Mon, 05 Mar 2012 00:22:44 -0000, S Viemeister wrote:

On 3/4/2012 3:23 PM, Rod Speed wrote:
S Viemeister wrote
Tim Watts wrote
Lieutenant Scott wrote

Filaments use a fortune in electricity and are very hot so tend to damage the light socket.

What?? I have never seen a heat damaged lamp socket.

I have. Three pendant sockets - they were like that when we moved in.
But I suspect the previous owner had used heat lamps in them.

You dont have to use heat lamps in them, just have them vertical
and have high power bulbs in them, and low quality bakelite sockets.

I suspected the heat lamps on two, because there _was_ a heat lamp in
the third one...

Am I missing something here? Heat lamps are what you use in lizard cages to keep them warm, why would you put one in a domestic light?

--
http://petersparrots.com
http://petersphotos.com

Hickory dickory dock, three mice ran up the clock. The clock struck one, and the others got away with minor injuries.

Lieutenant Scott wrote:

Am I missing something here? Heat lamps are what you use in lizard
cages to keep them warm, why would you put one in a domestic light?

Where I used to live, I was tempted to install one in the bathroom,
which had no other heat source.

Then I moved, and Winter happened in my new house, which has central
heating.
--
Tciao for Now!

John.

On Mon, 05 Mar 2012 11:45:23 -0000, John Williamson wrote:

Lieutenant Scott wrote:

Am I missing something here? Heat lamps are what you use in lizard
cages to keep them warm, why would you put one in a domestic light?

Where I used to live, I was tempted to install one in the bathroom,
which had no other heat source.

Then I moved, and Winter happened in my new house, which has central
heating.

Just how powerful are these heat lamps, considering it's usually a 5 amp circuit?

--
http://petersparrots.com
http://petersphotos.com

Women, you're in good shape as long as you can still touch your toes.
Just remember, using your boobs doesn't count.

On Mon, 05 Mar 2012 11:55:10 -0000, Lieutenant Scott wrote:

Just how powerful are these heat lamps, considering it's usually a 5 amp
circuit?

Not very few hundred watts, but they are designed to produce longwave
infrared which warms objects that are iluminated by them rather than
light.

--
Cheers
Dave.

On Mon, 05 Mar 2012 12:15:19 -0000, Dave Liquorice wrote:

On Mon, 05 Mar 2012 11:55:10 -0000, Lieutenant Scott wrote:

Just how powerful are these heat lamps, considering it's usually a 5 amp
circuit?

Not very few hundred watts, but they are designed to produce longwave
infrared which warms objects that are iluminated by them rather than
light.

Ah, the irritating kind of heat, and the one that sets fire to things :-)

--
http://petersparrots.com
http://petersphotos.com

What does Michael Jackson like about twenty-eight year olds?
The fact that there are twenty of them.

On 3/5/2012 6:45 AM, John Williamson wrote:
Lieutenant Scott wrote:

Am I missing something here? Heat lamps are what you use in lizard
cages to keep them warm, why would you put one in a domestic light?

Where I used to live, I was tempted to install one in the bathroom,
which had no other heat source.

Then I moved, and Winter happened in my new house, which has central
heating.

Yes, there was a heat lamp in the pendant fitting in the bathroom, and
the fittings in the front and back hall both looked 'cooked'.
All replaced, now!

On 2012-03-04, John Williamson wrote:

Andrew Gabriel wrote:
In article ,
harry writes:
Carbon filiment??????? I thought THEY went out 90-100 years ago?

They came back as horribly inefficient decorative lamps a few years
ago (were available in B&Q, and may still be).

They've always been available for laboratory use from lab suppliers,
normally for imaging their filaments through optics (e.g. pin-hole
cameras).

They have an interesting failure mode - if the glass cracks and air
gets in, they normally explode at next switch-on.

110 years old and still going...

http://www.centennialbulb.org/photos.htm#anchor1234

I'm sure they're running it in ideal conditions.

On 2012-03-04, Andrew Gabriel wrote:

Tim Watts writes:
Rod Speed wrote:
Tim Streater wrote

Yes, what is it with this screw-in **** that seems to be creeping in?

Its basically a better design.

Unless you have metal casing forming the main socket screw thread, and you
use it in a country where polarity is not guaranteed - eg touching the lamp
neck (eg whilst unscrewing) gives you a shock.

This results in some electrocutions (IIRC, about 2 in the US per year).

In the USA, screw fittings are considered safer because the live
terminal is "buried" inside the holder. Everything in modern American
wiring is polarized now, so the outside threaded bit should always be
neutral. I suspect that the shocks there are all associated with
incorrect wiring (in which case, the screw fitting is worse, of
course).

Dave Liquorice wrote:

Not very few hundred watts, but they are designed to produce longwave
infrared which warms objects that are iluminated by them rather than
light.

One problem was infrared lamp bulbs intended for use in dry
locations being sold for use in bathroom fittings. Condensation
tended to cause thermal stresses and dramatic failure, in a
situation where you really don't want a shower of broken glass.

:-(

Chris
--
Chris J Dixon Nottingham UK


Have dancing shoes, will ceilidh.

On Mar 5, 11:55*am, "Lieutenant Scott" wrote:
On Mon, 05 Mar 2012 11:45:23 -0000, John Williamson wrote:
Lieutenant Scott wrote:

Am I missing something here? *Heat lamps are what you use in lizard
cages to keep them warm, why would you put one in a domestic light?

Where I used to live, I was tempted to install one in the bathroom,
which had no other heat source.

Then I moved, and Winter happened in my new house, which has central
heating.

Just how powerful are these heat lamps, considering it's usually a 5 amp circuit?


Google "pig lamp"

On Mar 5, 3:02*pm, Adam Funk wrote:
On 2012-03-04, Andrew Gabriel wrote:

* *Tim Watts writes:
Rod Speed wrote:
Tim Streater wrote
Yes, what is it with this screw-in **** that seems to be creeping in?

Its basically a better design.

Unless you have metal casing forming the main socket screw thread, and you
use it in a country where polarity is not guaranteed - eg touching the lamp
neck (eg whilst unscrewing) gives you a shock.

This results in some electrocutions (IIRC, about 2 in the US per year).

In the USA, screw fittings are considered safer because the live
terminal is "buried" inside the holder. *Everything in modern American
wiring is polarized now, so the outside threaded bit should always be
neutral. *I suspect that the shocks there are all associated with
incorrect wiring (in which case, the screw fitting is worse, of
course).

The latest two pin lampholder here (UK) are completely shielded when
the bulb is removed.

In article
,
harry wrote:
On Mar 5, 3:02 pm, Adam Funk wrote:
On 2012-03-04, Andrew Gabriel wrote:

Tim Watts writes:
Rod Speed wrote:
Tim Streater wrote
Yes, what is it with this screw-in **** that seems to be creeping in?

Its basically a better design.

Unless you have metal casing forming the main socket screw thread, and you
use it in a country where polarity is not guaranteed - eg touching the lamp
neck (eg whilst unscrewing) gives you a shock.

This results in some electrocutions (IIRC, about 2 in the US per year).

In the USA, screw fittings are considered safer because the live
terminal is "buried" inside the holder. Everything in modern American
wiring is polarized now, so the outside threaded bit should always be
neutral. I suspect that the shocks there are all associated with
incorrect wiring (in which case, the screw fitting is worse, of
course).

The latest two pin lampholder here (UK) are completely shielded when
the bulb is removed.


really? I could put a finder in without any difficulty ;-(

--
From KT24

Using a RISC OS computer running v5.18

Lieutenant Scott wrote
S Viemeister wrote
Rod Speed wrote
S Viemeister wrote
Tim Watts wrote
Lieutenant Scott wrote

Filaments use a fortune in electricity and are very hot so tend to damage the light socket.

What?? I have never seen a heat damaged lamp socket.

I have. Three pendant sockets - they were like that when we moved
in. But I suspect the previous owner had used heat lamps in them.

You dont have to use heat lamps in them, just have them vertical
and have high power bulbs in them, and low quality bakelite sockets.

I suspected the heat lamps on two, because there _was_ a heat lamp in the third one...

Am I missing something here?

Likely.

Heat lamps are what you use in lizard cages to keep them warm,

They are used for a lot more than just that.

why would you put one in a domestic light?

Consumers can do the silliest things.

Corse as you imply, just because one pendant had a heat lamp in it, doesnt mean that the others did.

And why would they have removed 2 and not all 3 ?

On Mon, 05 Mar 2012 18:07:21 -0000, harry wrote:

On Mar 5, 11:55 am, "Lieutenant Scott" wrote:
On Mon, 05 Mar 2012 11:45:23 -0000, John Williamson wrote:
Lieutenant Scott wrote:

Am I missing something here? Heat lamps are what you use in lizard
cages to keep them warm, why would you put one in a domestic light?

Where I used to live, I was tempted to install one in the bathroom,
which had no other heat source.

Then I moved, and Winter happened in my new house, which has central
heating.

Just how powerful are these heat lamps, considering it's usually a 5 amp circuit?


Google "pig lamp"

I'm not quite sure this is what you had in mind: http://farm3.static.flickr.com/2796/...d3111261cd.jpg

--
http://petersparrots.com
http://petersphotos.com

If you want a stable relationship....buy a horse.

On Mon, 05 Mar 2012 18:31:49 -0000, Rod Speed wrote:

Lieutenant Scott wrote
S Viemeister wrote
Rod Speed wrote
S Viemeister wrote
Tim Watts wrote






I have. Three pendant sockets - they were like that when we moved
in. But I suspect the previous owner had used heat lamps in them.

You dont have to use heat lamps in them, just have them vertical
and have high power bulbs in them, and low quality bakelite sockets.

I suspected the heat lamps on two, because there _was_ a heat lamp in the third one...

Am I missing something here?

Likely.

Heat lamps are what you use in lizard cages to keep them warm,

They are used for a lot more than just that.

why would you put one in a domestic light?

Consumers can do the silliest things.

Corse as you imply, just because one pendant had a heat lamp in it, doesnt mean that the others did.

And why would they have removed 2 and not all 3 ?

The bulbs had gone?

--
http://petersparrots.com
http://petersphotos.com

Gary Glitter has said if he gets executed he wants cremating and his ashes putting in an etch-a-sketch, so the kids can still play with him!