[TCUG] Re: LED Heads
- From: David B Thompson <DBT@xxxxxxxxxxxxxxxxxxxx>
- To: tcug@xxxxxxxxxxxxx
- Date: Thu, 16 Oct 2003 09:43:00 +0100
Most LED's that I have seen installed have the opposite problem, where the
change is very "crisp". This can sometimes look odd where there is a mixture
of normal lamps and LED's, for example where the LED's have been used for
high level signals.
I do seem to remember that at least one of the newer LED heads, from either
Siemens or PEEK has been made to look more like a tungsten lamp, by using
the "on board" microprocessor chip to give more of a ramp to the switch on
and switch off of the lamp.
The only other time I have seen all lamps on together on tungsten lamp
sites, is where there was a loose common neutral in the head/polecap. I
would not have thought LED's would be affected in the same way.
Dave
===== Original Message from tcug@xxxxxxxxxxxxx at 15/10/03 17:24
>Hi All,
>
>Does anyone have any issues with latency on LED Heads? Here in Warrington,
>we have just installed our first LED signal heads and have noticed an issue
>due to delays in aspects extinguishing. We are witnessing situations where
>for approx. 600ms all aspects are illuminated on a change from Red/Amber to
>full green. Anyone have any thoughts?
>
>Andy Ashton
>Design & Implementation (UTC)
>Warrington Borough Council
>
>
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