What wire size do I need to install my JuiceBox®?

One common question we are asked is "What size circuit breaker do I need?" and in turn that follows with "What size wire do I need?"

The following table from the NEC (National Electrical Code via the NFPA) is used to find the proper size wiring based on the circuit needs. In most cases, "continuous load" is never even a thought when planning the circuit to be installed, but Electric Vehicles that are charging must take this into consideration, per the NEC. 


NOTE: For the installation wiring, please have your electrician size the conductors for both rated wire temperature and 125% continuous load. Please refer to both the National Electrical Code (NEC) and your local Authority Having Jurisdiction (AHJ) for any additional requirements.1


1The neutral wire is not used, but may need to be present in the receptacle.

625.41 which states:

Overcurrent protection for feeders and branch circuits supplying electric vehicle supply
equipment shall be sized for continuous duty and shall have a rating of not less than 125 percent
of the maximum load of the electric vehicle supply equipment. Where non-continuous loads are
supplied from the same feeder or branch circuit, the overcurrent device shall have a rating of not
less than the sum of the non-continuous loads plus 125 percent of the continuous loads.

Please see our article on Load sharing  if you plan to take advantage of this feature.

Please note that the NEC is a minimum requirement, and some jurisdictions will adopt their own code in conjunction with the NEC which may be different than that stated above.  Always check with your local Authority Having Jurisdiction for local codes.

Contact us at support@evcharging.enelx.com if you have more specific questions.