SACRAMENTO (CBS13) — It’s the one thing that impacts every single drive on our roads, and one of the most-often asked questions from CBS13 viewers: How are traffic lights timed?

We’ve all been there and we’ve all wondered why it seems like we’re hitting every red light.

Timing is everything, especially behind the wheel, but how are the traffic signals timed? We got our answer by going inside the belly of the traffic beast, the Sacramento County Traffic Operations Center. That’s where experts monitor 116 cameras—with more on the way—to track 450 signals, most of which can be controlled from the center.

“We detect all our signal approaches and that’s how we base the timing for the different directions,” said Doug Maas.

They detect the approaches by using sensors placed under or near the road at every signaled intersection. That means if a driver doesn’t trigger that sensor the light could stay red longer than it should.

Tonight at 10: What happens if your car is tied to a red-light violation and you weren’t driving? A woman says this happened to her and was linked to the scene by the appearance of her eyebrows. We look the process and why the woman feels guilty until proven innocent.

“So you have to get within 50 feet of the crosswalk or the limit line before it knows you’re there,” he said.

That’s on a smaller side street. Bigger streets have sensors that detect cars a lot sooner. Overall signal timing is set based on research computerized and out in the field. It factors in how many vehicles travel the road and whether it’s a pedestrian-heavy intersection among other factors.

But what’s the most congested intersection in Sacramento County where you’re likely to be seeing red for awhile.

“Watt [Avenue] and Fair Oaks [Boulevard] is our busiest intersection,” he said. “It’s probably our most difficult to time because once you get to a certain capacity and you go over that capacity, you just can’t serve everybody.”

There is also a maximum time a light will stay green in the county that varies by intersection. It’s 25 seconds for a left turn, 40 seconds for a minor side street, and the main streets get 70 seconds of green.

Heavy traffic and accidents can change everything, leaving Maas and his team to make adjustments.

“We can change that here and we can do that in real-time iif we see something that needs to be adjusted based on timing,” he said.

Experts say nine out of 10 drivers who see a yellow from far enough away will stop, but it can get ugly for that one driver who guns it.

“We time the signals based on keeping people from seeing yellow in that one zone,” he said.

One of the biggest problems facing traffic experts is drivers on their smartphones either stopping short of road sensors to send a text and not trigger the signal, or being so distracted they sit behind the wheel on their phone and actually miss a light that just turned green.