What is a base can?

The buried housing under a light, and the first place AGL meets the civil works: it is built into the pavement, so everything about it has to be agreed on site.

SIDE SECTION · A BASE CAN IN PAVEMENT FINISHED SURFACE PAVEMENT (CIVIL WORKS) PRIMARY CABLE IN PRIMARY CABLE OUT FIXTURE ON FLANGE GROUT / CONCRETE BED SECONDARY CABLE UP ISOLATING TRANSFORMER GRAVEL SUMP TO DRAIN / FREE-DRAINING GROUND WHERE CIVIL MEETS AGL 1 POSITION & LEVEL Set to the lighting layout 2 ORIENTATION Flange bolts aligned to the beam 3 CABLE ENTRIES Conduits to the duct bank 4 DRAINAGE Gravel sump and outlet 5 LOAD & SEAL Wheel loads; sealed to pavement
primary cable
secondary cable
isolating transformer
fixture
The Fact Civil interface

A base can is a cylindrical housing, usually metal, buried in the ground or pavement. The fixture bolts to its top flange, the primary cable enters through conduit entries, and a deep can also holds the isolating transformer and connectors.

It is a civil interface because it is part of the pavement structure as well as the lighting system. The can is placed during pavement construction, or core-drilled into finished pavement and grouted in, so its position, flange level, orientation, cable entries and drainage must be agreed between the civil and AGL teams before the surface is closed.

Deep can

Holds the transformer and connectors directly under the light.

Shallow can

Carries the fixture only, often an inset light. Transformer sits in a nearby housing or pit.

RoleMounts the fixture and shelters the connections below it
Civil sidePosition, depth, bedding, grout and pavement seal
AGL sideFlange height, bolt orientation, conduit entries
DrainageGravel sump or drain so the can stays dry
RatingMust carry aircraft wheel loads when flush with pavement
ReferenceFAA AC 150/5345-42 · ICAO Doc 9157 Pt 5
Schematic — sizes, depths, materials and tolerances differ between products and standards. Follow the manufacturer’s installation data and the applicable standard (ICAO / FAA). Connections in a can may be on a live series circuit: isolate, lock out and prove dead before opening it or touching any cable.
Start of Division 18 Entry 2 · Transformer pits

Frequently Asked Questions

Q1What is a base can in airfield ground lighting?

A buried cylindrical housing, usually metal, set into the pavement or ground. It carries the light fixture on its top flange, takes the cables in through conduit entries and, in deep designs, holds the isolating transformer and connectors.

Q2Why is a base can called a civil interface?

Because it is built into the civil works. It is positioned during pavement construction or core-drilled and grouted into finished pavement, so its level, position, orientation and drainage must be agreed between the civil and AGL teams.

Q3What is the difference between a deep and a shallow base can?

A deep can is tall enough to hold the transformer under the light. A shallow can carries only the fixture, often an inset light, and the transformer sits in a separate housing or pit nearby.

Q4Why must the can flange be set to the right level?

The fixture bolts to the flange, so the flange sets how high the light sits against the finished surface. The fixture is set to the height the standard and the manufacturer specify against the finished surface, and spacer rings allow adjustment, including after resurfacing.

Q5Why do base cans need drainage?

Standing water around the transformer and connectors degrades insulation and corrodes fittings. A gravel layer or drain connection under the can lets water leave, and a good seal at the top keeps surface water out.

Q6Where are base-can requirements defined?

FAA AC 150/5345-42 covers light bases, transformer housings and junction boxes, and ICAO Aerodrome Design Manual Part 5 covers electrical systems. Confirm against the current edition and the manufacturer's installation data.

Precision AGL Academy

See It. Understand It. Then Learn How to Engineer It.

Recognising an AGL system visually is the first step. The next step is knowing how to design, install, test, commission and maintain them correctly.

Build Practical AGL Engineering Skills

Go deeper with structured training from Precision AGL Academy, covering:

AGL Fundamentals Design & Electrical Engineering Approach Lighting Photometry Installation & Commissioning Maintenance & Troubleshooting

Learn how each light, sign and circuit works as part of a complete airport lighting system, not just as an isolated diagram.

See. Understand. Apply. Engineer.