What is connector inspection?
A close, hands-on check of the connectors in an airfield lighting circuit, looking for water, corrosion, cracks and heat damage before they cause a fault. In a series circuit, one poor primary-side connection can affect every light on the loop.
Connectors join the primary cable to each isolating transformer, the transformer to its light through a short secondary cable, and the lengths of cable to each other. Most sit in a base can or transformer pit beside the light, protected but still reachable. Because the lights are in series, a connector that is wet, corroded or cracked can raise resistance, leak current to earth or open the circuit, and on the primary side the effect is felt well beyond that one light.
1Make it safe first
Isolate and lock out the circuit and prove it dead, as your site procedure requires, before any can or pit is opened. Never disconnect a primary connector on a live series circuit. Work on the airfield only with the right permission and under the site’s safety rules.
2Look closely
Open the can or pit and note what you find before you touch anything: water, silt or debris, and the condition of the lid. Then check each connector for a cracked, split or cut boot or moulding, corrosion on metal parts, heat marks or discolouration, and a connector that is loose or not fully mated. Look at the cable too: strain or a tight bend at the connector puts load on the seal.
- Prove the circuit dead first
- Photograph defects where they are
- Log against circuit and location
- Disconnect a primary connector while live
- Pull on cables to test a connector
- Leave a damaged connector in service
3Record and act
Photograph each defect, log it against its circuit and location, and raise the repair or replacement. Where the cause is unclear, insulation-resistance testing helps confirm the condition, and the circuit is discharged afterwards. Close up carefully, refit the lid so it is not a trip or water path, and restore the circuit only as your procedure allows.
| Check point | What to look for |
|---|---|
| Base can or pit | Water, silt, debris, damaged lid |
| Boot or moulding | Cracks, splits, cuts, soft or swollen areas |
| Metal parts | Corrosion, green or white deposits |
| Heat marks | Discolouration or melted areas mean a high-resistance joint |
| Mating | Fully seated, not loose or pulled apart |
| Cable at the connector | Strain, hard bends, damaged sheath |
| Identification | Labels readable and matching the circuit |
| Record | Dated photo, location, circuit and action |
Frequently Asked Questions
Q1Why are AGL connectors inspected?
Because the lights are in a series circuit, one poor primary-side connection can affect the whole circuit, while a poor secondary connection usually affects one light. Inspection finds water, corrosion, cracked mouldings and heat damage before they turn into a fault or a failed test.
Q2Can a connector be inspected with the circuit live?
No. Inspection is a de-energised, hands-on check. Isolate and lock out the circuit and prove it dead as the maintenance plan and site rules require, and never disconnect a primary connector on a live series circuit.
Q3What defects should be looked for on a connector?
Look for a cracked, split or cut boot or moulding, corrosion on metal parts, heat marks or discolouration, water or silt in the base can or pit, a connector that is loose or not fully mated, and cable strained or bent hard at the connector.
Q4Where are the connectors that need inspecting?
Mostly in base cans and transformer pits beside the lights: primary connectors at each isolating transformer, secondary connectors between transformer and fixture, and in-line joints in the primary cable.
Q5What happens after a defect is found?
Photograph it, log it against its circuit and location, and raise the repair or replacement. Where the cause is unclear, insulation-resistance testing, with the circuit discharged afterwards, helps confirm the condition before the connector is replaced.
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