Low-Voltage Lighting Systems

These systems drop line voltage down through a listed transformer or power supply, so the wire you bury in the flower bed is safe to handle even when energized.

The trick is using a listed system and not overloading the run — long, thin low-voltage wire drops voltage fast, and cheap connectors corrode outdoors. Do it right and it is one of the friendliest jobs in the trade.

When it applies

Low-voltage lighting covers those landscape path lights, deck accents, and display fixtures running at thirty volts or less. A listed transformer or power supply steps the line voltage down to a level that is safe to touch, which is why you can bury and route these cables far more freely than line-voltage wiring.

Common mistakes

• Using an unlisted or improvised power source instead of one listed for the purpose.
• Undersizing the low-voltage cable for a long run, so the far fixtures dim from voltage drop.
• Burying secondary cable carelessly where a shovel finds it, even though it is low voltage.

In the field

I space the transformer taps and cable runs so the last light in the yard is as bright as the first. Customers notice when the end of the path fades out, and it is almost always voltage drop, not a bad lamp.