Low-Voltage Landscape Transformers

What does a low-voltage lighting transformer do?

A low-voltage transformer steps 120-volt line power down to 12 to 15 volts, the safe range landscape and many LED fixtures run on. It is the power source for the entire low-voltage circuit, sized to the total fixture load. Pool, spa, and outdoor systems use sealed, wet-location-rated versions.

How do I size a landscape lighting transformer?

Add the wattage of every fixture, then add about 20% headroom. A run totaling 200 watts needs at least a 250-watt transformer. Staying under the rated load keeps the transformer cool and leaves room to add fixtures later. Common sizes run 60, 150, 300, and 600 watts.

What is a multi-tap transformer, and how does it fix voltage drop?

Long wire runs lose voltage, dimming distant fixtures. A multi-tap transformer offers several output terminals — typically 12V, 13V, 14V, and 15V — so you wire far fixtures to a higher tap to compensate. Aim to deliver 10.5 to 12 volts at every fixture for consistent brightness.

What's the difference between a magnetic and electronic transformer?

Construction and weight differ. A magnetic (core-and-coil) transformer is heavy, rugged, and the standard for outdoor landscape runs. An electronic transformer is lighter and more compact but suits smaller, often indoor loads. For dimming, the transformer type sets the dimmer — magnetic pairs with MLV, electronic with ELV.

Do landscape transformers include timers and photocells?

Many do. A built-in timer runs the lights on a set schedule, and a photocell (dusk-to-dawn sensor) switches them on at dark and off at dawn. Combined timer-plus-photocell models turn on at dusk and off at a set hour. Stand-alone photocells and timers add control to basic units.

Building the low-voltage system? Add dusk-to-dawn control with Photocells, match a dimmer to the transformer type in LED Dimmers, compare electronic options in LED Drivers, and browse the fixtures it powers in Outdoor Lighting.