What is the base?
The lower part of the fixture that fixes the light to its base can in the ground. It sets the fixture’s position and direction, seals the joint and lets the cable in.
A light must be fixed firmly to the ground, aimed in the right direction and kept dry. The base is the part of the fixture that does this job.
1It fixes the light to the base can
The base is usually a mounting flange or plate with a bolt pattern that matches the base can set in the ground. Flange bolts hold it down, and the height and level set where the light sits relative to the surface.
2It aims, seals and lets the cable in
An orientation mark and bolt pattern fix the direction the fixture faces. A seal closes the joint. The cable enters through the can’s cable entry and rises through the opening in the base, and the can drains through its floor to a gravel sump so water does not collect around the joint.
3Fit it flat, clean and square
Clean the faces, fit the seal, and tighten the bolts evenly to the specified torque. Look for a rocking or tilted flange, missing or corroded bolts, a displaced seal, wrong orientation and standing water at the joint.
| Element | Detail |
|---|---|
| Base | Lower part of the fixture that fixes it to its foundation |
| Parts | Mounting flange or plate, bolt holes, orientation mark, seal face, cable opening |
| Fixes to | Base can set in the ground, concrete or pavement |
| Must match | Base-can bolt pattern, height and orientation |
| Protects | The joint and cable entry from water and dirt |
| Check | Flat clean flange, bolt torque, orientation, seal, water at the joint |
Frequently Asked Questions
Q1What is the base of an airfield light fixture?
The lower part of the fixture that fixes it to the foundation, usually a mounting flange or plate bolted to a base can set in the ground, with an opening for the cable to enter.
Q2How is the base different from the base can?
The base can is the buried housing set in the ground, concrete or pavement. The fixture base is the part of the light that sits on and fixes to it. They must match in bolt pattern and height.
Q3What should be checked on the base?
Check that the flange is flat and clean, the bolts are present and tightened to the specified torque, the orientation mark is correct, the seal is intact and no water is collecting in or around the joint.
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