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Traffic Signal

Product

Overview

The traffic signal is a complete intersection-approach system: a stacked three-section vehicle head, pedestrian signals and call stations, and a roadside controller cabinet that computes phase timing and switches the field outputs. LED modules have replaced incandescent balls for their long life, low power, and high bright-sun visibility, while a conflict monitor in the cabinet enforces safety by flashing the intersection on any fault.

How it works

The Vehicle Signal Head stacks three polycarbonate sections, each with a hinged door, gasket, and tunnel visor, fitted with red, yellow, and green LED Signal Module units. Each module seals an LED Array Board of discrete LEDs driven at constant current behind a prismatic colored lens, and a reflective backplate raises conspicuity. A serrated clamp positions the head over the lane.

Pedestrians are served by the Pedestrian Signal Module, a hand/person display with a countdown digit board, and the Pedestrian Push Station, a vandal-resistant piezo call button with an instruction sign.

The brain is the Controller Cabinet, a roadside enclosure holding the Traffic Controller Board that computes phase timing, plug-in Load Switch cards driving each signal channel, a Conflict Monitor (MMU) MMU that flashes the intersection on conflicting greens or voltage faults, a Detector Card reading inductive loops, a service power supply, and field terminals. A Pole / Mast Mount Kit suspends the heads over the roadway.

Bill of materials for Traffic Signal

7 top-level lines as of r175448
# Item / sub-assembly Part no. Qty/assy Ext. qty Parts Type
1 Vehicle Signal Head 8 parts traffic-signal-head 1× 1 0 assembly
2 Pedestrian Signal Module 4 parts traffic-signal-ped-module 1× 1 0 assembly
3 Pedestrian Push Station 4 parts traffic-signal-push-station 1× 1 0 assembly
4 Controller Cabinet 8 parts traffic-signal-controller-cabinet 1× 1 0 assembly
5 Pole / Mast Mount Kit 2 parts traffic-signal-mast-mount-kit 1× 1 0 assembly
6 Wire Bundle wire-bundle 1× 1 · part
7 Fastener Set fastener-set 2× 2 · part

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