What is lamp replacement?
Swapping a failed lamp for the same type and rating — with the circuit isolated first and the fixture cleaned, resealed and tested afterwards — so the light returns to full output and stays dry.
Lamp replacement is changing a failed lamp for a new one of the same type and rating 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.
Many AGL lamps are halogen: let a lit lamp cool and keep skin off the glass, because oil can cause hot spots and early failure. Fit only the specified lamp, since a different type or wattage changes the output and the load on the isolating transformer. Renew the gasket or O-ring, clean the optics, refit to the manufacturer’s torque, then restore the circuit, check the lamp and record the work.
- Isolate. Switch off the circuit, lock it out and tag it, and prove it dead under the permit-to-work.
- Cool. Let a lamp that has been lit cool before handling it.
- Open. Remove the cover or fixture as the manufacturer instructs and take out the failed lamp.
- Fit. Fit the new lamp of the same type and rating, handling it by the base or with clean gloves.
- Clean and seal. Clean the lens and reflector, check the seat and renew the gasket or O-ring.
- Close, restore, test. Refit to the specified torque, restore the circuit, check the lamp lights and its output is normal, and record it.
Frequently Asked Questions
Q1What is lamp replacement in airfield ground lighting?
Lamp replacement is changing a failed lamp in an AGL fixture for a new one of the same type and rating, and returning the fixture to a clean, sealed and tested condition. LED fixtures have no replaceable lamp; they use an LED module instead.
Q2Why must the circuit be isolated and locked out first?
AGL lamps are fed from a series circuit that carries hazardous current. The work is done with the circuit switched off, locked out and proved dead under the airport's permit-to-work, and the lock stays on until the fixture is closed up again.
Q3Why must the replacement be the same type and rating?
A lamp of a different type or wattage changes the light output and the load on the isolating transformer, and can overload it. The fixture's optics are also designed around a specific lamp. Always fit the type the manufacturer specifies.
Q4Why should the lamp glass not be touched?
Many AGL lamps are halogen. Skin oil on the glass can create hot spots when the lamp is lit and shorten its life. Handle the lamp by its base or with clean gloves, and let a lamp that has been lit cool before handling it.
Q5Why renew the gasket or O-ring?
The seal keeps water and dirt out of the fixture. A used or damaged seal can let in moisture, which corrodes the contacts and shortens the life of the new lamp. Renew it and make sure the sealing faces are clean and undamaged.
Q6What is checked after the lamp is replaced?
That the lamp lights, that its output looks normal compared with neighbouring lights, that the fixture is sealed and refitted to the specified torque, and that the circuit current is normal. The work is then recorded in the maintenance log.
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