The standard rating of the overcurrent protection device supplying a 240-V, 60-A electric vehicle charger should be ___.

• A. 60 A
• B. 70 A
• C. 75 A
• D. 80 A

Answer: (D)

The protection rating must account for the EV charger operating continuously. For continuous loads, the overcurrent protection device is sized at 125% of the continuous current. A 60 A charger can draw up to 60 A for long periods, so 60 × 1.25 = 75 A. Since 75 A isn’t a standard breaker size, you choose the next standard size up, which is 80 A. This provides adequate protection for the conductors while accommodating the charger’s continuous operation.