LED Traffic Light Installation Guide: Foundation, Wiring and Commissioning

Last updated: 25 June 2026 | Reading time: ~10 minutes | By GAOQIAO Traffic Engineering Team

Installing an LED traffic light at an intersection involves several engineering disciplines: civil (foundation), structural (pole mounting), electrical (wiring and grounding) and traffic engineering (timing, phasing and conflict monitoring). This guide walks through each step in the order they happen on site, with the practical checkpoints GAOQIAO's engineering team has refined over 17 years of export projects.

Before you start: site survey and documentation

Before any excavation or pole delivery, confirm the following are in place:

For the pole and signal head hardware itself, the project's packing list should be cross-checked against the delivery. GAOQIAO ships pole, signal head, mounting brackets, anchor bolt cage template and the wiring diagram in matched crates. Browse the signal arm pole and double arm pole ranges for the typical hardware kits.

Step 1: Foundation

The foundation carries the full wind load on the pole plus the moment from the cantilever arm. For a 6-meter single-arm pole on normal soil, typical foundation dimensions are 1.2-1.5m deep by 0.6-0.8m wide, with an anchor bolt cage tied to rebar and concrete grade C25 or C30. For taller poles, multi-arm configurations or poor soil conditions, the foundation is engineered case-by-case.

Practical checkpoints on site:

  1. Excavate to the design depth. Verify soil bearing capacity matches the assumption.
  2. Place the anchor bolt cage using the template. Check bolt projection and pattern against the pole base plate drawing.
  3. Pour concrete with the specified grade. Use a vibrator to eliminate air pockets.
  4. Cure for at least 7 days before pole erection. Do not load the foundation early.

Step 2: Pole and arm erection

Once the foundation has cured, lift the pole onto the anchor bolts. Level the pole base with metal shims, then torque the anchor nuts in a star pattern to the value specified on the foundation drawing. For single-arm and double-arm configurations, attach the arm after the vertical pole is plumb.

Where the signal heads will mount on a horizontal arm, confirm the arm orientation matches the approach lane geometry before final tightening. The vertical pole and traffic signal board configurations each have their own orientation notes shipped with the hardware.

Step 3: Signal head installation

Mount the signal heads at the heights and orientations shown on the intersection drawing. A standard 300mm signal head weighs roughly 7-12 kg per aspect depending on housing material; the head-mounting bracket must be rated for the load and the wind area of the head plus visor.

Run the signal head cables through the pole's internal cable channel to the base handhole, then through the underground conduit (or surface-mounted cable tray) to the controller cabinet. Leave a service loop at each head junction box to allow head removal for maintenance.

Step 4: Wiring to the controller and power

Cable Typical Specification Use
Signal head load cable RVV 4 x 1.5 mm² (or 4 x 2.5 mm² for longer runs) From each head aspect to the controller cabinet output.
Detection / signal cable RVVP 4 x 1.0 mm² shielded Vehicle detector loops or radar feedback to the controller.
Power supply (mains) YC or YJV 3 x 4 mm² or larger From utility connection to the cabinet, with proper grounding.
Solar DC PV 1 x 4 mm² or 1 x 6 mm² From solar panel to charge controller; from battery to DC bus.

Terminate cables at the controller cabinet following the wiring diagram shipped with the traffic light controller. Verify phase rotation, neutral and ground continuity before energizing. For solar systems, confirm the charge controller sees the correct battery voltage before connecting the load.

Safety checkpoint: Always perform a lockout-tagout on the upstream breaker before working inside the cabinet. Energize the system in stages: cabinet power first, then each signal head, then the detection inputs.

Step 5: Commissioning

Commissioning is the step where the intersection goes live under controlled testing. A typical sequence:

  1. Lamp test: Use the controller's lamp test function to verify every LED aspect illuminates at full brightness. Look for dim or flickering aspects — usually a sign of a loose terminal.
  2. Phase plan: Confirm the controller is running the timing chart from the engineering drawing. Verify phase order, interval lengths and offsets.
  3. Conflict monitoring: Trigger the conflict monitor (CMU) by simulating a green-green conflict. The CMU should drop the cabinet to flash within the specified time.
  4. Detection check: For each approach, simulate a vehicle call and verify the controller responds as designed.
  5. Visibility check: Drive each approach at design speed and confirm the signal heads are visible from the design stopping sight distance.

For solar-only intersections, the commissioning sequence also includes a 24-72 hour battery autonomy test under simulated or actual solar conditions. See the technical support page for project-specific commissioning templates.

Planning an intersection installation or export project?
Request engineering support and a quotation →

Frequently asked questions

What foundation depth is required for a traffic light pole?

Foundation depth depends on pole height, wind zone and soil bearing capacity. A typical 6-meter signal pole on normal soil uses a 1.2-1.5m deep foundation with an anchor bolt cage. GAOQIAO provides an engineered foundation drawing with every pole quotation, calculated for the project's wind and soil conditions.

What cable is used for traffic light wiring?

Signal head wiring commonly uses RVV or RVVP shielded cable (typically 4x1.5mm² or 4x2.5mm²) for the load side, with separate grounding conductors. For solar traffic lights the same cable is used but the conductor sizing is matched to the lower DC current. Always follow the cable specification in the project's electrical drawing.

How long does a typical intersection installation take?

For a standard 4-way intersection with 4 signal poles and one controller cabinet, plan 5-10 working days for foundation, pole erection, head mounting, wiring and commissioning. Solar-only intersections install faster because trenching and cable pulling are minimized.

Do GAOQIAO products include installation drawings and documentation?

Yes. Every shipment includes a foundation drawing, signal head outline drawing, wiring diagram and a bill of materials. For OEM/ODM projects, we also provide 3D models and installation videos on request.


About GAOQIAO — Nanjing Gaoqiao Traffic Technology Co., Ltd. is a Chinese LED traffic light manufacturer with 17+ years of project export experience. Our accessories and spare parts, traffic light remoter and entrance-exit speed board lines cover the full intersection hardware stack. View our certification page for the full compliance list.