Andrew Gabriel wrote:
In article ,
The Natural Philosopher writes:
stevelup wrote:
Surely the primary reason for using them in traffic lights is to reduce
ongoing maintainance costs?

Yes. Unfortunately, the first generation turned out to be very
short lived before the LEDs died.

That as well.
But there are enormous energy savings to be had as well.

Traffic lights are not normally on a metered supply in this country.
This was an important reason in the US, where they are more often
metered, and where they use inefficient mains bulbs. UK traffic
lights have used LV halogen bulbs for decades, which are much more
efficient than mains signal bulbs in the first place.

Not significantly when they've got a filter over the front.

The message
from Ian Stirling contains these words:

Oh what a good idea - now traffic lights can be jammed, probably
accidentally.

I'm all in favour that that. Most places the traffic flows much better
once the lights go off.

--
Skipweasel
Pay no attention to that man behind the curtain.

On 20 Nov 2006 22:17:49 GMT, (Andrew
Gabriel) wrote:

UK traffic
lights have used LV halogen bulbs for decades, which are much more
efficient than mains signal bulbs in the first place.

I recall seeing some traffic lights being replaced about 5 years ago
with LED's. The old units were partially broken and sat on the grass
verge next to the junction for a couple of days awaiting disposal. At
least one of the light elements, I think it might have been green
although I can't be sure, had a circular fitting that looked like a
fluorescent type.


--

In article ,
Matt writes:
I recall seeing some traffic lights being replaced about 5 years ago
with LED's. The old units were partially broken and sat on the grass
verge next to the junction for a couple of days awaiting disposal. At
least one of the light elements, I think it might have been green
although I can't be sure, had a circular fitting that looked like a
fluorescent type.

Any side signs (such as a no right turn sign) are fluorescent.

--
Andrew Gabriel

On 22 Nov 2006 21:38:43 GMT, (Andrew
Gabriel) wrote:

In article ,
Matt writes:
I recall seeing some traffic lights being replaced about 5 years ago
with LED's. The old units were partially broken and sat on the grass
verge next to the junction for a couple of days awaiting disposal. At
least one of the light elements, I think it might have been green
although I can't be sure, had a circular fitting that looked like a
fluorescent type.

Any side signs (such as a no right turn sign) are fluorescent.

It *looked* like the head off a normal 3 light system, the only reason
I could have been confused on the colour was it might have been
inverted and the front casing surround and coloured filters were
missing completely.



--

In article ,
Matt wrote:
I recall seeing some traffic lights being replaced about 5 years ago
with LED's. The old units were partially broken and sat on the grass
verge next to the junction for a couple of days awaiting disposal. At
least one of the light elements, I think it might have been green
although I can't be sure, had a circular fitting that looked like a
fluorescent type.

I would have thought fluorescents not that suitable for constantly being
switched on and off - even the best ones don't always trigger at the same
speed. You'd really need some sort of mechanical shutter to work reliably
- thus decreasing the efficiency.

--
*The longest recorded flightof a chicken is thirteen seconds *

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

On Thu, 23 Nov 2006 11:15:30 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
Matt wrote:
I recall seeing some traffic lights being replaced about 5 years ago
with LED's. The old units were partially broken and sat on the grass
verge next to the junction for a couple of days awaiting disposal. At
least one of the light elements, I think it might have been green
although I can't be sure, had a circular fitting that looked like a
fluorescent type.

I would have thought fluorescents not that suitable for constantly being
switched on and off - even the best ones don't always trigger at the same
speed.

Precisely what I thought, I could just about make out the connector
pins on the end of the tube and they looked identical to a normal
striplight tube. The tube was about 3/4 of the max circumference maybe
1 1/2" diameter.

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