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How Signal Timing Works

Traffic signal operation varies by intersection. Each controller has its own phase order, timing plan, and safety intervals.

PRIORITYwave can request a manual advance. It cannot override pedestrian timing, clearance intervals, emergency vehicle preemption, or other controller safety behavior.

Learn the Intersection​

Before actively controlling a new intersection, observe multiple full signal cycles. Learn the normal order of movements, which directions move together, where protected turns appear, and how long pedestrian intervals usually last.

Take time to understand:

  • Which movements go first and which follow.
  • Pedestrian walk, flashing hand, and clearance timing.
  • Protected turn behavior and any movements that run separately.
  • The typical duration of each movement.
  • Whether the intersection uses preemption, coordination, or special timing.
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Assume nothing at a new intersection. Two intersections that look similar in the field may have different controller programming, pedestrian timing, protected turns, or agency procedures.

Pedestrian Timing Can Delay a Change​

If a pedestrian phase is active, the controller may hold the current vehicular movement until the pedestrian clearance interval has completed. This can happen even when vehicles appear stopped or when the operator has already sent an advance command.

This means:

  • A valid RF or touchscreen command may not change the signal immediately.
  • The controller may wait for a pedestrian countdown or clearance timer to end.
  • The vehicle signal may remain green while a flashing hand interval completes.
  • A second command may be needed after the controller becomes ready for the next manual advance, depending on the cabinet and local configuration.

This is expected controller behavior, not a PRIORITYwave fault.

One Press May Not Move the Signal Immediately​

In many installations, pressing the remote or touchscreen during a green or walk phase starts or continues pedestrian clearance. After that clearance time ends, the next accepted advance can move the signal through yellow and red so the next movement can receive green.

Watch the signal after every command. Do not assume that one button press will always produce the same visible response at every intersection.

Safety Timers Still Win​

The traffic controller remains responsible for safe operation of all programmed phases. PRIORITYwave can request an advance, but it cannot shorten required clearance timing, skip protected intervals, or force movement against controller safety logic.

If a command is accepted by PRIORITYwave but the signal does not immediately advance, wait for the controller to finish any active safety interval before sending another command.

Emergency Vehicle Preemption​

Emergency vehicle preemption may take priority over manual control. During a preemption event, the controller may change automatically for the responding vehicle and then return to manual operation after the event ends.