Traffic lights and pressure pads
Traffic lights and pressure pads
Author
Discussion

eiger120

Original Poster:

159 posts

251 months

Thursday 12th April 2007
quotequote all
I have just read an old post on jumping red lights which got me thinking....

There is a set of traffic lights on the way to work which are operated by a pressure sensor. The reason for the pressure sensor is to minimise disruption to the flow of traffic on the primary road (allowing a right turn onto the secondary road only when there is traffic in the right hand 'slip' lane). This is fine when in a car but the pad is not sensitive enough to be triggered by the weight of the bike. I tend to leave early (before 5am) and as a result there is very rarely traffic at the junction. Given the layout of the junction, the visibility of the approaching roads and lack of traffic I feel I could consider it safe to ignore the red light.

If I am at the front of the queue then I have to pull over the white line in order to allow a car to pull up behind me onto the pad.

Both situations put my license at some risk of points, fines etc. The obvious thing for me to do now when on a bike is to carry on past the traffic lights, do a U turn then come back and turn left down the secondary road. The main traffic lights aron a timer / sensor so there is no problem. However the first time I rode this route it had me a little confused as to why after 5 minutes the lights had not changed. It is impossible to pull out of the slip lane back onto the primary road due to traffic islands.

My question to the floor is what would be the recommended course of action if approaching this junction for the first time on a bike (with no other traffic)?

herewego

8,814 posts

243 months

Thursday 12th April 2007
quotequote all
Turn across the road just before the lights. Hop off and run across the pavement at the junction then hop back on again, so avoiding the lights altogether.

eltax91

10,779 posts

236 months

Thursday 12th April 2007
quotequote all
By the way the OP suggested he was "risking his license" i think he means a motorbike, rather than a push bike!

Andrew D

968 posts

270 months

Thursday 12th April 2007
quotequote all
Not that it makes any difference but here's a little factoid of the day:-

The rectangular cuts in the road surface before traffic lights aren't actually pressure pads but rather induction loops. The cuts aren't where the surface has been removed but simply grooves into which wires are laid. As large masses of metal pass over them a signal is generated in the loop which informs the control unit of the presence of a vehicle. Which is probably why they don't detect your bike, it's probably not a sufficiently large mass.

I suspect that the problem isn't systematic to all induction loops, but rather a specific fault at that location.

cabinet enforcer

503 posts

256 months

Thursday 12th April 2007
quotequote all
Andrew D said:
I suspect that the problem isn't systematic to all induction loops, but rather a specific fault at that location.


Agreed, induction loops can quite easily pick-up motorbikes, and indeed pushbikes.

BO55 VXR

4,373 posts

281 months

Thursday 12th April 2007
quotequote all
When I were kid...many moons ago, the local railway station car park had one of these on the barrier for the exit.

If I cycled over the center of the loop, nothing would happen, but if I cycled along one edge, actually on the induction loop line (the rubber bit) it would open the barrier.

You could see if that works for you