Where are the connector locations?

The few points on a series circuit where cables are joined: at each transformer, out to each light, along the cable, and at the regulator.

SERIES CIRCUIT · WHERE THE CONNECTORS SIT CCR TRANSFORMER BASE CAN / PIT TRANSFORMER BASE CAN / PIT IN-LINE JOINT regulator end PRIMARY-SIDE CONNECTORS: THE WHOLE LOOP DEPENDS ON EACH CONNECTOR LOCATIONS PRIMARYat the transformer, in and out SECONDARYtransformer to fixture IN-LINEwhere cable lengths are joined REGULATOR ENDcable termination at the CCR SCHEMATIC · NOT A WIRING DIAGRAM · ARRANGEMENT VARIES BY LIGHT TYPE AND DESIGN
primary connector / joint
secondary connector
isolating transformer
fixture
The Fact Series circuit

Connections in an AGL layout sit in four places. Primary connectors join the primary cable to each isolating transformer, in and out, so the series circuit passes through it. A secondary connector joins the short secondary cable between the transformer and the fixture. In-line joints connect lengths of primary cable, and the primary cable is terminated at the regulator.

Most of these connectors live in a base can or transformer pit beside the light, protected from water and traffic but still reachable for testing and replacement. Because the lights are in series, one poor primary-side connection can affect the whole circuit, while a poor secondary connection usually affects one light, so their positions are planned for access, and they are checked during inspection and insulation-resistance testing.

Primary side

Series circuit current. Connectors at the transformer, along the cable and at the regulator.

Secondary side

Short isolated cable from the transformer to the light, with its own connector at the fitting.

Primary connectors Transformer primary, cable in and out
Secondary connector Transformer to light fitting
In-line joints Where cable lengths are joined
Typical housing Base can or transformer pit
Why it matters A bad primary or in-line joint affects the whole series loop; a secondary joint usually affects one light
Reference FAA AC 150/5345-26 (L-823) · ICAO Doc 9157 Part 5
Schematic — not a wiring diagram. Connector type, housing and layout depend on the light type, the circuit design, the standard (ICAO / FAA) and the manufacturer.
Entry 26 · Secondary cable routing Entry 28 · Base-can arrangement

Frequently Asked Questions

Q1What are connector locations in an AGL layout?

The points on a series circuit where cables are joined by connectors or splices: at the isolating transformer, between the transformer and the light, along the primary cable where lengths are joined, and at the regulator end.

Q2Where are the primary connectors?

Normally at the isolating transformer, where the primary cable comes in and goes out, so the circuit runs through the transformer in series. The transformer and these connectors usually sit in a base can or transformer pit beside the light.

Q3Where is the secondary connector?

On the short secondary cable between the isolating transformer and the light fitting. With the circuit isolated and proved dead, it lets the fixture be unplugged and replaced without disturbing the primary circuit.

Q4Why are connectors kept in base cans or pits?

So they are protected from water, traffic and damage, and can still be reached for inspection, testing and replacement. A connector buried with no access is difficult to test or repair.

Q5What goes wrong at connectors?

Moisture, corrosion, poor crimps and damaged seals can raise resistance or reduce insulation resistance. In a series circuit a bad primary-side connection affects the whole loop, while a bad secondary connection usually affects one light, so connectors are checked during inspection and insulation-resistance testing.

Q6Where are the standards for connectors?

FAA AC 150/5345-26 covers plug and receptacle cable connectors (L-823), and ICAO Aerodrome Design Manual Part 5 covers electrical systems. Always confirm against the current edition and the manufacturer's installation data.

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