What is the AGL control-system architecture?
The chain that lets an operator switch the lights and see how they are doing: commands travel down to the regulators, status travels back up.
An AGL control system is a chain of layers. An operator at the control position sends a command to the control and monitoring system, which passes it over a communications network to a substation controller. That controller tells the CCRs to set the brightness step or switch the circuit, and the CCRs feed the series circuits and the lights.
Information flows both ways. Commands go down, and status, faults and alarms come back up so the operator and maintenance staff can see the state of every circuit. Because losing control of the lights matters to operations, designs commonly add redundant paths and a local manual mode at the substation, plus interlocks for functions such as stop bars and lead-on lighting.
Operator to CCR. Commands such as on, off and brightness step.
CCR back to operator. Circuit status, faults and alarms.
Frequently Asked Questions
Q1What is an AGL control-system architecture?
The arrangement of equipment that lets an operator switch airfield lights and set their brightness, and see their status. It links a control position, a control and monitoring system, a communications network, local controllers and the constant-current regulators.
Q2What are the main layers of the architecture?
The control position (for example in the tower), the central control and monitoring system, the communications network, substation or local controllers, and the CCRs that supply the series circuits. Commands travel down this chain and status comes back up.
Q3What does the control system send to the lights?
Commands such as circuit on or off and the brightness step, and for selected circuits specific settings such as stop-bar or lead-on control. Each CCR sets the current of its series circuit to match the selected step.
Q4What does the monitoring side report?
Circuit status, brightness step, regulator faults and alarms, and depending on the design circuit-level insulation or lamp-outage information. This feedback lets operators and maintenance staff see problems early.
Q5Why is the network often redundant?
Because losing control of the lights affects operations. Many designs use duplicated servers, a ring or dual network, and a local manual mode at the substation so lights can still be controlled if the network or control position fails.
Q6Where are the requirements defined?
In ICAO Annex 14 Volume I (electrical systems) and the Aerodrome Design Manual Part 5, and for FAA-regulated airports in FAA AC 150/5345-56 (lighting control and monitoring systems). Always confirm against the current edition and the project specification.
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