What transformer size for landscape lighting?

For most residential landscape lighting systems, you'll need a 300-600 watt transformer, though the exact size depends on your total wattage requirements and future expansion plans.

The transformer size calculation is straightforward: add up the wattage of all your landscape lights, then multiply by 1.25 for safety margin. For example, if you have twenty 20-watt LED landscape lights (400 watts total), you'd need at least a 500-watt transformer. However, most electricians in New Brunswick recommend going slightly larger to accommodate future additions to your lighting system.

LED vs. Halogen makes a huge difference in transformer sizing. Modern LED landscape lights typically use 3-7 watts each, while older halogen fixtures can use 20-50 watts. If you're installing new LED landscape lighting, a 300-watt transformer can handle 15-20 path lights plus accent lighting. For larger properties with extensive lighting plans, 600-900 watt transformers are common.

Location matters significantly in New Brunswick's climate. The transformer must be installed in a weatherproof enclosure and positioned where it won't be damaged by ice, snow removal, or flooding during spring melt. Many NB electricians install transformers in garages or sheds rather than outdoors to protect from our harsh Maritime weather. The transformer should be easily accessible for maintenance but secure from tampering.

TSANB requirements apply to landscape lighting installations. While replacing individual light fixtures typically doesn't require a permit, installing new low-voltage circuits and transformers usually does. The transformer must be properly grounded and connected to a GFCI-protected circuit. Most installations require a dedicated 15 or 20-amp circuit from your electrical panel.

Professional installation is recommended because improper transformer sizing can cause lights to dim, flicker, or fail prematurely. Undersized transformers run hot and fail early, while oversized transformers waste energy. A licensed electrician can calculate your exact needs, ensure proper GFCI protection, and handle the TSANB permit process.

For complex landscape lighting with multiple zones, timers, and photocells, consider multiple smaller transformers rather than one large unit. This provides better voltage regulation and allows independent control of different lighting areas.

Need help finding an electrician for your landscape lighting project? New Brunswick Electrical can match you with local professionals who specialize in outdoor electrical work and understand our Maritime climate requirements.