April 26, 2008

Proper installation of inground landscape fixtures is more important than in above-ground applications. This is because the underground environment exposes the fixture to many risks and hazards that are not isues for above-ground fixtures. Before we get into the step-by-step instructions for installing an inground LED landscape light it is important to know some general rules for these types of installations.

General rules for installing in-ground landscape lights

• Never place the fixture below grade. If the fixture is placed below grade it will become a sump, collecting dirt and debris and possible becoming submerged in water in wet weather.
• Do not place plant flowers, plants or trees too close the the fixture. As the flowers, plants or trees grow they will block the light produced by the luminaire.
• Keep mulch and ground cover away from the fixture. The mulch acts as an insulator and will trap heat inside the fixture. LED landscape lights are especially sensitive to heat and excess heat may cause them to fail.

Step-by-step instructions for installing in-ground landscape lighting

1. Excavate soil where fixture is to be place and wire and/or conduit will be run. Make sure that the fixture is elevated above the grade and that the grade slopes away from the fixture. Be sure to dig deep enough to provide a minimm of 3" of drainage material (sand and pea stone or gravel) below the fixture housing.
2. Remove the trim ring and all internal components from the fixture housing (except for the moisture asorbing dessicant pack attached the side of the housing and set these aside.
3. Install 3" of drainage material in the hole excavated for the housing. Use sand and pea stone or gravel.
4. Place the fixture housing into the hole and back fill around it with a minimum of 3" of drainage material (sand or gravel) around the side of the housing. Be sure that the underside of the housing flange rests on top of grade level.
5. Install the conduit and/or wiring to housing using a watertight fitting and pull supply wires through to housing.
6. Press duct seal compound into wire entryway and then fill the entire entryway with two-part potting compound to seal the conduit and/or wire entry point from moisture.
7. Reinstall ballast tray. Use silicon wire nuts to connect supply wire to fixture wire within housing.
8. Reinstall balance of electrical components. Plug lamping module into quick connect, if applicable.
9. Install the gasketed lens making certain there is no debris between the gasket and the housing. Install trim ring or rock guard per installation intructions.
10. Connect fixture to power source