"Scott" wrote in message
...
On Mon, 5 Sep 2016 20:13:21 +0100, Nightjar wrote:

On 05-Sep-16 7:18 PM, misterroy wrote:
On my way to work a bridge is being repaired. Today I was in the stream
of traffic heading towards town, no cars going the other way. Mid stream
the lights went red, just as I reached them. I went through. I reckon I
travelled 100m between the lights and then about 600m up the hill before
the lights changed.
I realise there has to be a margin to be sure a car gets through, but
how big should the margin be?
Why when the lights have sensors do they never seem to be switched on?
It just looks like a crude timer is used.
Under what circumstances are the sensors on the lights used?


Modern temporary traffic lights always use traffic sensors.

Can traffic sensors always detect cycles?

I guess they could if the aimed them onto the pavements.



--
Adam