What does a complete AGL system look like?
Power flows out to the lights, control sits over the top, and the earthing network runs underneath: the whole system on one page.
A complete AGL system has four parts working together. A power chain runs from the supply, through the substation and its CCRs, out along series circuits, to an isolating transformer in a base can at each light and then to the fixtures and signs.
A control and monitoring layer sits above it, sending commands down and bringing status back up. An earthing network runs underneath, along the cable routes, tying the regulator, base cans and metal equipment to earth. The earlier entries in this section each zoom into one piece of this picture.
Supply to substation and CCRs, series circuits, transformers and lights.
Control above for commands and status. Earthing below for protection.
Frequently Asked Questions
Q1What is a complete AGL system architecture?
The whole airfield lighting system seen as one: power supply, substation and regulators, series circuits, isolating transformers and fixtures, with a control and monitoring layer above and an earthing network beneath.
Q2How does power reach an airfield light?
Utility power, backed by a standby supply, feeds the substation. A constant-current regulator (CCR) turns it into a series circuit current, the primary cable carries it around the airfield, and an isolating transformer at each light steps it to what the fixture needs.
Q3Why are airfield lights on series circuits?
A series circuit carries the same current through every light, so lights on one circuit have matching brightness at each step. Isolating transformers keep the circuit running when a lamp fails.
Q4What does the control and monitoring layer do?
It lets operators switch circuits and set brightness steps from the control position, and reports status, faults and alarms back. It sits above the power chain and talks to the CCRs.
Q5Where does the earthing network fit?
It runs underneath the whole system, along the cable routes and tied to the regulator, base cans and metal equipment. It gives lightning and fault currents a controlled path to earth.
Q6Where are the system requirements defined?
In ICAO Annex 14 Volume I (Chapters 5 and 8) and the Aerodrome Design Manual (Doc 9157) Parts 4 and 5, and for FAA-regulated airports in FAA AC 150/5340-30 and the related equipment specifications. Always confirm against the current edition and the project specification.
See It. Understand It. Then Learn How to Engineer It.
Recognising an AGL system visually is the first step. The next step is knowing how to design, install, test, commission and maintain them correctly.
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Learn how each light, sign and circuit works as part of a complete airport lighting system, not just as an isolated diagram.