What is LED driver replacement?
Swapping a faulty LED driver for the approved one — after confirming the fault and isolating the circuit, fitting it matched to the module and resealing the fixture — so the light returns to steady, correctly stepped output.
LED driver replacement is changing a faulty LED driver for the approved driver for that fixture and returning the fixture to a clean, sealed and tested condition. Series circuits carry hazardous current, so isolate, lock out and prove the circuit dead before opening any fixture, under the airport’s permit-to-work.
The driver sits between the isolation transformer and the LED module and regulates the current the LEDs receive. Because one driver feeds the whole module, a failure usually shows as every LED dark, flickering or off-step rather than a few dead LEDs. Confirm the fault first, as a poor connection or a damaged module can look the same. The driver, module and transformer are matched, so fit only the approved part. Then restore the circuit, check steady output at every brightness step, and record the work.
- Confirm. Under the permit-to-work, read the symptom (whole module dark, flickering or off-step) and check that neighbouring fixtures and the circuit current are normal, so the fault is really in this fixture. Supply and connection checks wait until the circuit is isolated.
- Isolate. Switch off the circuit, lock it out and tag it, and prove it dead.
- Open and inspect. Open the fixture as instructed. Look for water, heat marks, loose connectors and a poor thermal contact, and inspect the module before refitting.
- Remove. Disconnect the connectors, noting polarity, and take out the old driver as a unit.
- Fit and connect. Fit the approved driver, seated and fastened as specified. Latch the connectors with the polarity as marked and keep the leads clear of the seal.
- Seal, restore, test. Renew the gasket or O-ring, close to the specified torque, restore the circuit, and check steady output at every brightness step and normal circuit current. Record the work.
Frequently Asked Questions
Q1What is LED driver replacement in airfield ground lighting?
LED driver replacement is changing a faulty LED driver in an AGL fixture for the approved driver, and returning the fixture to a clean, sealed and tested condition. The driver is the electronics between the fixture's isolation transformer and the LED module. It regulates the current the LEDs receive, so the module lights steadily and follows the circuit's brightness steps.
Q2How do I know the driver is at fault and not the module?
A failed driver usually affects the whole module at once: fully dark, flickering or flashing across every LED, or the wrong brightness. Individual dead LEDs point to the module instead. Before replacing anything, check the pattern: one fixture points at the fixture side, several fixtures point at the loop, the CCR or the cabling. Then, with the circuit isolated, confirm the transformer secondary and the connections feeding the driver are good, because a poor connection or a damaged module can look like a driver fault. Follow the manufacturer's fault-finding instructions.
Q3Why must the replacement be the approved driver?
The driver is matched to the LED module, the isolation transformer and the way the fixture follows brightness steps. A different type can drive the LEDs at the wrong current, flicker, ignore the steps, run hot and shorten the life of the module. Fit the part the manufacturer specifies for that fixture and check the part number before it goes in.
Q4Why isolate and lock out before opening the fixture?
A series circuit carries hazardous current. The isolation transformer separates the fixture from the loop, but the primary side and the loop are still live while the CCR runs. Switch the circuit off, lock it out and tag it, and prove it dead under the airport's permit-to-work before the fixture is opened. Never leave the isolation transformer's secondary open-circuit while the circuit is energised.
Q5Should the LED module be replaced at the same time?
Not automatically. Inspect the module for heat marks, discolouration and damaged LEDs before the new driver goes in, because a failed module can damage a new driver. Replace the module only when the manufacturer's criteria say so, and record what was found.
Q6What is checked after the driver is replaced?
That every LED lights, that the light is steady with no flicker, that it follows each brightness step and matches neighbouring fixtures, that the circuit current is normal, and that the fixture is sealed and refitted to the specified torque. The work, the part fitted and the fault found are then recorded in the maintenance log.
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