Waterproof (IP67) Power Supplies & LED Drivers: A Practical Selection Guide
Outdoor LED projects fail in two predictable ways in Canada: water gets into the power supply, or the power supply was never big enough to begin with. Both are avoidable at checkout. Here's how to pick a sealed driver that survives a Canadian winter.
What IP67 actually promises
The IP code has two digits: the first for solids, the second for water. IP67 means dust-tight and protected against temporary immersion (up to 30 minutes at 1 m). For soffit lighting, deck lighting and garden transformers exposed to rain and snowmelt, IP65 is the working minimum and IP67 buys you margin for pooling water and ice. Indoors-only drivers (IP20) belong in dry ceilings and cabinets — never outside.
Size the wattage with 20% headroom
Add up the load, then buy bigger. A 5 m LED strip drawing 14.4 W/m needs 72 W — which means a 96 W driver, not a 75 W one. Drivers run cooler and last longer below ~80% of rated load, and cold starts in a Canadian January are hard on marginal units.
Constant voltage vs constant current
- Constant voltage (12 V / 24 V): for LED strips, puck lights and most retrofit projects. This is what most DIYers need.
- Constant current (350/700 mA…): for bare LED modules and some commercial fixtures — the fixture's spec sheet will say so explicitly.
Cable runs: don't lose your volts in the wire
Long low-voltage runs lose real voltage. A 24 V system tolerates distance far better than 12 V. Before you bury cable to a shed or gate, run the numbers in our free voltage drop calculator and check conductor sizing against the wire gauge / amperage calculator — two minutes that save a dim, flickering install.
Installation notes for cold climates
- Mount drivers vertically where possible so meltwater drains off the gland face.
- Use the supplied cable glands or outdoor-rated junction boxes — IP67 only holds if the entries are sealed.
- Check the operating temperature range; quality sealed drivers are typically rated to −30 °C or lower.
- Dimmable? Confirm the driver lists your dimming protocol (TRIAC, 0–10 V) — "dimmable" alone is not enough.
Frequently asked questions
Is IP65 enough for outdoor use in Canada?
IP65 handles rain and is fine under cover. Choose IP67 where snow can pile against the unit or water can pool — it is rated for temporary immersion.
Can I run a 12V LED strip from a longer distance?
Yes, but voltage drop grows quickly at 12V. Either upsize the wire gauge, move the driver closer, or switch the system to 24V.
How much wattage headroom should a LED driver have?
Plan for the driver to run at no more than about 80% of its rated wattage — a 72W load belongs on a 96W driver.