What is a connector?
The plug and receptacle that joins a fixture to its transformer. It carries the current, keeps water out, and comes apart cleanly when the fixture is serviced.
A fixture has to be joined to its supply, and it also has to come off for service. The connector does both. It is a plug on the fixture’s secondary lead that mates with a receptacle on the secondary lead of the isolating transformer, so a fixture can be unplugged and replaced without cutting any cable.
1It carries the current
Metal contacts held in an insulating body make a low-resistance joint between the two leads. A poor contact can overheat, make the lamp flicker or put the light out, so the contacts must be clean, tight and the right type.
2It keeps water out
The joint sits outdoors, often in a wet base or pit. A sealing boot, gasket or moulded joint keeps water and dirt away from the contacts, because water corrodes them and can break down the insulation or cause earth leakage.
3It must come apart and go back right
A locking feature holds the connector together against vibration and pulling, and a keyed shape stops it being fitted the wrong way. Look for corroded or burnt contacts, a cracked body, a torn seal or a connector not fully mated, and replace with the correct manufacturer part. Isolate the circuit and follow the site permit before any connector is separated or made.
| Element | Detail |
|---|---|
| Connector | Plug and receptacle that can be separated and re-made |
| Fixture side | Plug, on the fixture’s secondary lead |
| Transformer side | Receptacle, on the isolating transformer’s secondary lead |
| Parts | Contacts, insulating body, sealing boot or gasket, locking feature |
| Used at | Fixture secondary lead to the isolating transformer secondary |
| Material | Conductive contacts in a moulded insulating body, sealed against water |
| Typical faults | Corroded or burnt contacts, cracked body, torn seal, not fully mated |
| Reference | Manufacturer’s instructions; FAA AC 150/5345-26 (L-823); ICAO Doc 9157 Part 5; edition in force |
Frequently Asked Questions
Q1What is a connector in an airfield light fixture?
A plug on the fixture's secondary lead that mates with a receptacle on the isolating transformer's secondary lead. It carries the current through reliable contacts and lets the fixture be disconnected for service without cutting any cable.
Q2Why is the connector sealed?
Water in a connector can corrode the contacts, break down the insulation and cause earth leakage or a failed light. A sealing boot, gasket or moulded joint keeps water and dirt out of the contacts, and the seal must be intact and fully seated each time the connector is made.
Q3How is a connector different from a splice?
A connector is made to be separated and re-made, so a fixture can be removed and replaced quickly. A splice is a permanent joint made with a kit and is not designed to be taken apart. Which one is used depends on the design and the manufacturer's instructions.
Q4What faults do connectors suffer from?
Corroded, burnt or loose contacts, a cracked or damaged body, a torn or missing seal, water inside, and a connector that was not fully pushed home or locked. Each can cause a flickering or dead light, heating or earth leakage.
Q5Is it safe to disconnect a connector on a live circuit?
No. A series circuit carries a hazardous voltage when energised. Isolate the circuit, prove it dead and follow the site permit and the manufacturer's instructions before any connector is separated or made.
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