Lighting · CEC Section 30 & Low-Voltage Rules

Outdoor Lighting Load Calculator

Size your low-voltage 12V landscape transformer and wire gauge to prevent dim lights and voltage drop across garden, path, and patio runs.

1. Landscape Lighting Plan

Path Lights (3W LED each)

Spotlights / Uplights (6W LED each)

Deck / Step Lights (1.5W LED each)

Total Cable Run Length (ft from transformer)

2. Transformer & Wire Sizing

12V Landscape System

TOTAL LANDSCAPE WATTAGE

78 Watts

MINIMUM TRANSFORMER SIZE

100 Watt Transformer

RECOMMENDED LANDSCAPE CABLE

12/2 Direct Burial Cable

System Sized OK: 100W Transformer provides healthy headroom (under 80% maximum load).

Low-Voltage Installation Rules

12V Low-Voltage direct burial landscape cable (12/2 or 10/2) can be buried shallow (6 inches cover per CEC Class 2 rules).
120V line-voltage outdoor lighting (floodlights, post lights) requires NMWU cable buried 600 mm (24 in) deep or in conduit.
Always connect 12V transformers into a GFCI-protected weatherproof outdoor receptacle with an "in-use" bubble cover.

Low-voltage landscape loads

Typical LED fixture wattage for sizing a transformer.

Fixture	Typical LED watts
Path light	2–4 W
Spotlight	5–8 W
Flood light	10–15 W
Deck/step light	1–2 W
String lights (per 10 m)	5–10 W

Total the fixture watts and add 20% headroom — transformers shouldn't run above 80% of their rating.

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