How can you quickly troubleshoot a high-mast light that isn't working?
To quickly diagnose the fault on-site and save time, you can use the "step-by-step elimination method":
Stage 1: Power Supply. Using a multimeter and a voltage tester, first check the input voltage at the control box. If there is no voltage, proceed directly to the upstream distribution box; if voltage is present, move to the next stage.
Stage 2: Control Unit. Bypass the timer or photoelectric switch (by short-circuiting the "L" terminal and the load terminal with a wire). If the light turns on, the issue lies with the switch settings; if it does not, check the contactor. Manually press the contactor's armature; if the light turns on, the fault is in the control circuit (e.g., push-buttons or coils); if it remains off, proceed to the next stage.
Stage 3: Circuitry. Set your multimeter to the resistance (Ohms) mode and check the continuity of the circuit cables (ensure power is disconnected before testing). If the resistance for a circuit is infinite, the cable is broken or a connection has come loose; if the resistance is normal, move to the next stage.
Stage 4: Light Fixture. Remove the suspected faulty fixture and test it using a spare driver or by connecting it directly to an external power source. If the light turns on, the original driver or wiring was the problem; if it still does not light up, the LED chips are damaged.
Stage 5: Internal Junction Box. Open the cover of the junction box on the light array to check for signs of scorching or water ingress, and use a screwdriver to tighten all terminals. Following these five steps usually allows you to pinpoint the general location of the fault within 30 minutes. For lift-type high-mast lights, it is best to lower the light array to the ground before inspecting the fixtures and wiring to ensure safety and efficiency.
