I stand corrected! I got a note about my traffic light blog this week
from Chance Baxley here at my website. Chance and his co-workers
work with traffic lights and told me I was wrong about pressure plates.
Nope. No Pressure.
Electricity! There are wires laid into those cuts
you see in the pavement and they create what’s called an “inductance field.”
Chance tells me when a vehicle crosses over those wires, or “loops” as
they’re known, they detect the car’s metal and the cycle kicks in. He says
some loops are looped into coordinated systems that manage the flow of vehicles.
So that’s one reason why sometimes I don’t think the light “sees” my car.
It’s looking at the big picture. Although he did admit smaller cars could
be harder to detect because they have less metal in them. But there’s no
scientific proof of that. It still doesn’t change my basic premise. That
is you still have to pull up all the way to the line. Otherwise the system
may not detect your vehicle, big or small. And all of us behind you have
to pay for it. And my “zig-zagging” theory is still workable because I’m
making sure the loops detect me being, well, loopy! So thanks for the correction.
When it comes to telling you about traffic I don’t want to take any chances.
1 Comment to No Pressure
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December 7, 2009
Also if you think that your car isn’t being detected, cut the engine off and then start it. The starter motor that starts the engine will give off enough electromagnetic energy for the inductance coil to pick up your presence.
Works best for motorcycles.