Hello @ccap41 I have an 80amp circuit breaker with my 50amp charger, delivering 11kW to the auto steadily. Works great, certified and signed off by the city. Chargepoint manages the power to the auto, so the 80 is available to the charger, but it will not go past 50 unless the auto regulates the maximum input. This way any other EV I buy down the road can still get maximum power. Let me now put it in engineering speak: How an 80A Breaker Powers a 50A ChargePoint Unit When you have an 80A circuit breaker feeding a ChargePoint Home Flex unit rated for 50A output, the system works by matching the chargerās maximum draw to the breakerās capacity while following NEC continuous-load rules. 1. Continuous-load rule (NEC Article 625) EV chargers are considered continuous loads because they operate near full current for long periods. The National Electrical Code requires that the branch-circuit overcurrent protective device (breaker) be rated at least 125% of the EVSEās maximum load. For a 50A-rated charger: 50A Ć 1.25 = 62.5A ā rounded up to the next standard size, which is 70A. However, in practice, many installations use 80A breakers for 50A chargers because: The 125% rule applies to the equipmentās rated current, not the breakerās nominal rating. 80A is a common panel breaker size that safely handles 50A continuous load without nuisance tripping. It provides a margin for fault currents and transient surges. 2. How the 80A breaker ādoesā the work The breaker protects the conductors from overcurrent and short circuits. It disconnects the circuit if the current exceeds its rating, but at 80A, it will not trip during normal 50A charging. The actual charging current is limited by the chargerās output setting (e.g., 40A, 48A, or 50A) and the vehicleās onboard charger. The breakerās higher rating ensures the circuit can handle the continuous load without tripping, while still providing safety protection. 3. Wiring and installation considerations For a 50A charger, the conductors must be sized to carry the continuous load (e.g., 6 AWG copper for 50A at 60Ā°C). The breaker must be in a panel with enough capacity and space for the dedicated 240V circuit. Hardwired installation is often used for 50A chargers because plug-in installations are limited to 40A or 50A circuits ChargePoint. In short: The 80A breaker is sized above the NEC minimum (62.5A) to safely protect the wiring and equipment while allowing the 50A ChargePoint unit to deliver its full 11kW output. The breaker doesnāt ālimitā the chargerās power ā it just ensures the circuit can handle it without tripping, while still providing overcurrent protection. This information is gathered from the National Electrical Code website.
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