Track lighting

Track lighting is a method of lighting where light fixtures are attached anywhere on a continuous track device which contains electrical conductors. This is in contrast to directly routing electrical wiring to individual light positions. Tracks can either be mounted to ceilings or walls, lengthwise down beams, or crosswise across rafters or joists. They can also be hung with rods from especially high places like vaulted ceilings.

Typical systems have line voltage running through a recessed track. The track may have more than one live conductor, so that multiple switched circuits can be used to control different fittings on the same track. Installers will place the tab of the connector on the fixture to one side or the other when attaching it to the track.

There are three standard types of tracks used worldwide. They are often termed "H", "J", and "L" track, after the names of the manufacturers that established the standards, Halo, Juno, and Lightolier. To identify a track fixture, if it has three contacts, it is likely an "H" type. If the contact-tips are 1 inch apart, it is likely a "J" type, but if they are 7/8 inch apart, the track is likely an "L" type. Many systems now use a single live and then use digital control interfaces such as DALI to control the fittings. This means that each fitting can be independently controlled.

More modern systems are available with low voltage (10, 12, or 24 volts) running through the track, which is in itself decorative. In this case, the fixture may clamp onto a track made of two metal strips separated with an insulating strip. Two-circuit configurations are rare in such systems. The track is powered by a transformer which converts the high voltage into low voltage. There are magnetic and electronic transformers.

It is common to see line-voltage tracks with low-voltage fixtures. For these, each fixture requires a small transformer to operate it. For all low-voltage fixtures or systems a special dimmer (if used) is required, as standard dimmers are cheaply made and will cause flickering because of the interaction with the inductive electrical load.

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