June 15th 13, 07:11 PM
posted to uk.transport.london
|
|
external usenet poster
|
|
First recorded activity at LondonBanter: Jul 2009
Posts: 1,484
|
|
Pelican Crossings
On 15/06/2013 14:20, Recliner wrote:
On Sat, 15 Jun 2013 14:13:55 +0100, Basil Jet
wrote:
On 2013\06\15 11:32, JNugent wrote:
On 15/06/2013 02:34, wrote:
On 15/06/2013 01:35, wrote:
In article , () wrote:
Hello,
I saw this about pelican crossings and the associated crossing
signals.
BTW, I've noticed for a while now that the green on pedestrian
crossing signals no longer flash flash, but rather go dark. Is that
because of the stress that the flashing signal puts on the bulb
filaments, thus meaning more money expended for bulbs, plus the
labour involved in changing them?
All new installations use LEDs so that is a diminishing problem if it
exists
at all.
And the old ones? Because here in London the green pedestrian crossing
phases turn off, rather than flash.
Could this be due to the differences between proper Real Lamps
(incandescent ones) and the newer Pretend Lamps which have very poor
performance just when turned on or off and are of limited value for
signalling purposes for that reason?
Except that modern traffic lights are LEDs which have excellent response
times and are therefore perfect for signalling.
Indeed, and the effect is very obvious with the many road vehicles
(even buses) that have LED indicators. They really do switch on and
off instantly compared to the old incandescent bulbs. The next
Mercedes S Class will ditch incandescent bulbs entirely, using nearly
500 LEDs instead, thus saving power, performing better and largely
eliminating the need to replace failed bulbs.
That will put an additional premium on the price, no doubt.
|