Lighting question
 

"Andy Burns" wrote in message ...
Ian Jackson wrote:

Mark Carver wrote:

Remind me how long fluorescent tubes have been in use domestically in
the UK ?

I first started using CFLs four or five (?) years ago.

Over 20 years here (in fact I moved some of them from the previous house because they *were* expensive back then).

Yes, I was introduced to them in the mid '80 in a hotel, the 4 pin type with
a separate ballast (so there was little point in stealing the lamps)
It was not coincidental that I was introduced to the concept of "noise floor"
on RF distribution systems at the same time.

--
Graham.

%Profound_observation%

Lighting question
 

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember "
saying something like:

On the subject of lights and the olden
days, when we went on a school trip it was usually by train so we used
to steal the light bubs out of the carriages. I can't remember what
voltage they were but they were the normal BC fitting. It was good fun
to put one in a pendant fitting at school or at home and then watch
when an aldult turned the light on. They flashed very bright indeed
then of course went out. Happy days of innocent childhood.

50 or 60V iirc, from doing just that.

Lighting question
 

On Oct 10, 2:03*pm, "Graham." wrote:
When I was at junior school in the mid/late 1950s the classrooms had
fluorescents. We were told when the school opened that it was the
first school in the West Riding to have them, but that probably wasn't
quite true because a lot of identical schools were built at that time..
The lights were unreliable and the teachers used to have to whack the
starters with their canes.

Are you making this up? In an traditional glow-type starter, the switching is done by a bimetallic strip (similar to the ones
used in some thermostats) encased in an airtight glass bubble filled with a special gas. When you power up the fluorescent light,
the gas heats up (and glows of course), causing the two strips of metal to bend and touch, which then switches on the heater
filmaent at each end of the flourescent tube.
As soon as the strips touch and make the circuit, the gas cools down again, the strips separate again, and the lamp starts
glowing.

I think the heater filaments are on all the time to ensure the gas is ionised at a reasonable voltage. The starter interrupts the
supply to generate an extra large voltage using something like the induction coil in a car to start off the conduction.

At least that's how I've always thought they worked.

No they run in cold cathode mode once struck. The circuit is very simplehttp://tinyurl.com/33nudbu

The contacts must get welded together, a whack will often separate them, I
just assumed everyone knew *that :-)

--
Graham.

It's beginning to look as if Jamie was wrong then.

Bill

Lighting question
 

On Sun, 10 Oct 2010 17:18:56 +0200, Martin wrote:

If you kick German street lamps they go into sulk mode and switch off
for about 20 minutes.

With some street lamps, one only has to walk past them and give them
a nasty look and they will switch off.

Lighting question
 

" wrote in message
...

It's beginning to look as if Jamie was wrong then.

More a case of the gnomes piling on and doing the usual "I'm sidin' wiv Bill!"
routine I suspect.

In my original post I conceded the possibility that some alternative starter
technology was in use back then, which I suspect was the case if your story is
true, although your additional tale of the lights flickering and the students
"having fits" suggests otherwise.

In my view glow-type starters simply wouldn't have responded to a whack, if
they'd even jammed in the first place.
They only tend to jam when some moron leaves a worn out tube flickering away for
days on end until the starter wears itself out - in this case you see the tube
in darkness, save for a dim glow at each end (the heater filaments). I've played
with such starters and no amount of whacking will revive them.

Additionally, the glass bubble in which the bimetallic strip resides is
free-moving inside the starter module, attached only by two thin metal legs at
the base. This free movement would reduce the peak force of the impact if they
were whacked.


jamie.
--

Lighting question
 

"Dave Plowfool" wrote in message
...

And if you actually knew what a bi-metal strip was you'd realise they can
'stick'or make a poor contact. 'Cured' by whacking - like so much else
in schools then.

Honestly Plowfool, you really are without clue.
Your insults are a feeble as your levels of knowledge, incidentally.

jamie.
--

Lighting question
 

"Graham." wrote in message
...

I think the heater filaments are on all the time to ensure the gas is
ionised at a reasonable voltage. The starter interrupts the supply to
generate an extra large voltage using something like the induction coil
in a car to start off the conduction.

At least that's how I've always thought they worked.


No they run in cold cathode mode once struck. The circuit is very simple
http://tinyurl.com/33nudbu

Thank you. Now we know.

--
Max Demian

Lighting question
 

j r powell wrote:

I've noticed the early starter modules were larger and had four pins instead of
two, but when I took one apart, only the two larger pins were connected
internally, and it contained the above-mentioned glow-type technology.

Older 4-pin thermal starters were replaced by 2-pin glow starters, for a
while, glow starters were available in a 4-pin housing (with two pins
un-connected) for compatibility with old fittings.

Lighting question
 

"Andy Burns" wrote in message
.. .
j r powell wrote:

I've noticed the early starter modules were larger and had four pins instead
of
two, but when I took one apart, only the two larger pins were connected
internally, and it contained the above-mentioned glow-type technology.

Older 4-pin thermal starters were replaced by 2-pin glow starters, for a
while, glow starters were available in a 4-pin housing (with two pins
un-connected) for compatibility with old fittings.


I suspected as much. By what mechanism did the thermal starters work, then?

jamie.
--

Lighting question
 

On 10 Oct, 08:31, charles wrote:

It could have been dirty contacts that needed a jolt. *I certainly know
that hitting older starters made them work.


Still does in my kitchen and garage.