What size breaker do I need for a Level 2 EV charger?

Most Level 2 EV chargers require a 50-amp breaker, though the specific size depends on your charger's amperage rating and must be 125% of the charger's continuous load per the Ontario Electrical Safety Code.

The breaker size calculation follows a specific formula under the OESC. For continuous loads like EV chargers, the breaker must be rated at least 125% of the charger's maximum current draw. Here's how this breaks down for common Level 2 chargers:

32-amp charger (most common residential): Requires a 40-amp breaker (32 × 1.25 = 40 amps). This includes popular models like the Tesla Wall Connector, ChargePoint Home, and most universal Level 2 units. These chargers typically deliver about 7.7 kW of power.

40-amp charger: Requires a 50-amp breaker (40 × 1.25 = 50 amps). These higher-powered units can deliver up to 9.6 kW, charging most EVs faster but requiring more electrical capacity from your panel.

48-amp charger: Requires a 60-amp breaker (48 × 1.25 = 60 amps). These are less common in residential applications but offer the fastest Level 2 charging speeds.

Wire sizing is equally important - you'll need appropriate gauge wire to match the breaker. A 40-amp breaker requires 8 AWG wire, while a 50-amp breaker needs 6 AWG wire. The circuit must also be GFCI protected when installed in garages or outdoor locations, which is typical for most EV charger installations.

Your electrical panel capacity matters significantly. Many Ottawa homes have 100-amp or 200-amp main panels. Adding a 40-50 amp EV charger circuit requires ensuring your panel has adequate capacity for this new load plus all existing electrical demands. If your panel is already near capacity, you may need a panel upgrade before installing the charger.

ESA permit and inspection are mandatory for EV charger installation in Ontario. The work must be performed by a licensed electrician who will pull the permit, install the dedicated circuit, and arrange for ESA inspection. Typical installation costs in Ottawa range from $1,200-$1,800 for a straightforward installation where panel capacity exists, or $3,000-$5,000 if a panel upgrade is needed.

For a free assessment of your electrical panel capacity and EV charger installation quote, Electrical Ottawa can evaluate your specific situation and ensure proper sizing for both safety and optimal charging performance.

---

Find a Licensed Electrician

Electrical Ottawa connects you with vetted, ESA-licensed electricians from the Ottawa Construction Network:Ottawa Electrical Contractors:

• Floodlight Electric
• Faulkner Electric
• Home Town Electrical Services