There’s a surge in roadworks across the UK this summer, as local councils utilise the £1.6 billion allocated by the government to mend potholes and repair deteriorated roads. And this means more temporary traffic lights are being installed.
However, understanding how some traffic light sensors operate could prevent you from endlessly staring at a red light waiting for it to change, according to experts at Select Car Leasing.
While some temporary lights operate on timers, others use sensors to gauge where the traffic is – and which direction should be given priority.
These systems employ microwave radar sensors (or microwave vehicle detectors – MVD) to identify approaching vehicles and adjust signal timings accordingly.
They send a signal to the controller when an approaching vehicle is detected, allowing the lights to change and manage traffic flow more efficiently.
But if you fail to get close enough to the traffic light, and therefore trigger the sensor, you could be waiting indefinitely for it to turn green.
Graham Conway, Managing Director at Select Car Leasing, explained: “Nobody enjoys being stuck at a traffic light waiting for it to turn green – but we suspect many motorists simply aren’t aware that their own driving habits could be making the problem worse.
“Many temporary traffic lights use radar sensors that require a vehicle to be close enough to trigger the light change. If a vehicle isn’t near enough, the lights will prioritise traffic coming from another direction where they can sense cars – leaving you unnecessarily stuck on red for an age.
“This can cause a traffic jam to build in one direction, which can take many rotations of the lights to clear, and potentially causing anger and frustration all round.
“Frustratingly, the same issue can be caused if a driver stops too close to the light itself, beyond the sensor. The light will then only change if someone pulls up behind them and triggers the sensor again.”
Select Car Leasing also debunks the myth that flashing your headlights at temporary traffic signals will activate the sensor and prompt them to turn green.
While this was the case for older traffic light systems, contemporary temporary traffic lights (or ‘TTLs’) aren’t engineered to operate in this manner as they lack light-detecting sensors.
Mr Conway added: “The sensors in modern traffic lights don’t respond to the light frequencies emitted by headlights – so it’s pointless flashing your lights at them in an attempt to speed-up the colour change process.
“You also risk dazzling other road users, which is an offence that risks a charge of driving without due care and attention.
“If you misuse your headlights, most drivers can expect a £100 fine and points on your licence, while more serious cases could see the fine hiked to £5,000 coupled with the threat of a driving ban.”