What is system integration?
Joining the tested parts — power, CCRs, controls, monitoring and interlocks — and proving they work together as one airfield lighting system.
System integration follows functional testing. Each part has already been proved on its own; now they are connected and checked together. Power and standby supply, CCRs and circuits, control panels, monitoring and interlocks must behave as one system, not as separate pieces.
The checks look at the links between parts: what happens on loss of mains, which control point has priority, whether the field state and alarms reach the displays, and whether linked systems such as stop bars follow their logic. Each result is recorded. A defect is isolated, fixed and re-tested. When the checks pass, the system is ready for the ALCMS interface.
- Power. Force a changeover between mains and standby, agreed with ATC and the aerodrome operator; time it against the required switch-over time and confirm CCRs restart cleanly.
- CCR links. Send commands; confirm they reach each CCR, map correctly and return status.
- Control. Operate from tower and local panels; confirm priority and mode changeover.
- Monitoring. Confirm field state and alarms show correctly, including loss of communication.
- Interlocks. Check linked systems such as stop bars and centreline lights, PAPI and signs, where fitted.
- Record. Log each result; isolate, fix and re-test any defect.
Frequently Asked Questions
Q1What is system integration in airfield ground lighting?
The commissioning stage where separately tested parts of the AGL system, such as the power supply, CCRs and circuits, control panels, monitoring and interlocks, are connected and proved to work together as one system. It follows functional testing.
Q2How is it different from functional testing?
Functional testing proves each circuit, brightness step and control works on its own. System integration checks the links between them: power changeover, control priority, status feedback, alarms and interlocks between different parts of the system.
Q3What is normally checked?
Mains and standby supply with changeover, commands reaching the CCRs, status returning to the displays, priority between tower and local control, alarm and communication-loss responses, and interlocks such as stop bars with taxiway centreline lights, where the design includes them.
Q4Why test power changeover during integration?
Loss of mains is a real operating event. Forcing a changeover shows whether CCRs restart cleanly, whether circuits return to their last setting and whether control and monitoring stay available, none of which a single-circuit test reveals. The measured switch-over time is checked against the value required for the runway category in ICAO Annex 14 Vol I Ch 8 (as short as 1 second for some Category II and III lights). Agree the test with ATC first.
Q5Is the ALCMS interface part of system integration?
System integration brings the field equipment and its controls together first. The ALCMS interface, with its screens, command mapping and reporting, is covered in its own entry and is checked once the underlying system works as one.
Q6What happens if an integration check fails?
The defect is recorded, the affected part is isolated, the cause is found and corrected, and the affected checks are repeated. Because parts interact, related checks may need repeating too. The record keeps the failure, the correction and the passing re-test.
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