If the input circuit breaker of the charger is 70 Amps, can the contractor install a smaller circuit breaker in his panel based on the 49.2 Amps input current of the charger?
The gauge of wire feeding the charger’s input is determined by the circuit breaker on the source panel. If the installer chooses a 50A breaker then 50A wire will be safe. Depending on the jurisdiction, NEC and local codes may speak to this issue. Local codes may address this question. If you install a 50A breaker in the supply panel you run the risk of nuisance trips if the charger is called on to operate at maximum output for any length of time. These nuisance trips will become more frequent with higher ambient temperature. A breaker sized the same as the charger’s input breaker will not be subject to such nuisance trips.
Related Questions
- If my meter is on the outside of the house and the service cable goes out the back of the meter directly into the back of the circuit breaker panel can I use the Powerkuff Wire Wrap?
- If the service meter is mounted on side of building, how far can the contractor go inside the building to install his service panel?
- What should be the height of the circuit breaker panel?
