You just installed and added your second of two JuiceNet enabled devices, but only have one electrical circuit. Good news, the JuiceNet servers allow you to share one electrical circuit safely while charging both vehicles.
For your electrician:
Code for Load sharing (NEC 2017)
625.42 Electric Vehicle Supply Equipment Circuit Rating
Former 625.14 has been revised and relocated to 625.41 as a result of Article 625 being reorganized. A new last sentence that includes provisions for an automatic load management system has been added to 625.41. The maximum electric vehicle supply equipment load on a service and feeder shall be the maximum load permitted by the automatic load management system. This revision provides relief from service upgrades in some cases, but an automatic load management system has to limit the load on the service to its capacity.
Code for Load sharing (NEC 2020)
625.42 Rating. The power transfer equipment shall have sufficient rating to supply the load served. Electric vehicle charging loads shall be considered to be continuous loads for the purposes of this article. Service and feeder shall be sized in accordance with the product ratings. Where an automatic load management system is used, the maximum equipment load on a service and feeder shall be the maximum load permitted by the automatic load management system.
Adjustable settings shall be permitted on fixed-in-place equipment only. If adjustments have an impact on the rating label, those changes shall be in accordance with manufacturer’s instructions, and the adjusted rating shall appear with sufficient durability to withstand the environment involved on the rating label. Electric vehicle supply equipment with restricted access to an ampere adjusting means shall be permitted to have ampere ratings that are equal to the adjusted current setting. Sizing the service and feeder to match the adjusting means shall be permitted. Restricted access shall prevent the user from gaining access to the adjusting means. Restricted access shall be accomplished by at least one of the following:
(1) A cover or door that requires the use of a tool to open
(2) Locked doors accessible only to qualified personnel
(3) Password protected commissioning software accessible only to qualified personnel
Code for Disconnecting Means (NEC 2020)
625.43 Disconnecting Means. For equipment rated more than 60 amperes or more than 150 volts to ground, the disconnecting means shall be provided and installed in a readily accessible location. The disconnecting means shall be lockable open in accordance with 110.25.
Please note when setting up your load sharing, that the overcurrent device (Circuit Breaker) cannot exceed the rated amount of a normal JuiceBox installation.
- Pro 75/ JuiceBox 80 with same must only go on a 100A breaker, and nothing larger
- JuiceBox 48 with same must only go on a 60A breaker, and nothing larger
- JuiceBox 40 with same must only go on a 50A breaker, and nothing larger
- JuiceBox 32 with same must only go on a 40A breaker, and nothing larger
Once you have the JuiceBoxes installed and connected to WiFi, please add them to a Load Group. It will allow a combined output per the NEC 125% rule. For example, a 50 amp circuit for two or more JuiceBox 40 units would split the available 40A.
NOTE: “Maximum Current” for the group (this is remembered even if offline) is specified below. Please follow this chart:
100A circuit breaker = 80A Maximum Current (A)-JuiceBox 75 or 80 only
60A circuit breaker = 48A Maximum Current (A)-JuiceBox 48 only
50A circuit breaker = 40A Maximum Current (A)-JuiceBox 40 only
40A circuit breaker = 32A Maximum Current (A)-JuiceBox 32 only
*30A circuit breaker = 24A Maximum Current (A)-only if an adapter is used
*20A circuit breaker = 16A Maximum Current (A)-only if an adapter is used
The boxes will default to 6A and will start there, checking to see if it is sharing so as not to trip the circuit before it gets the server command. When one car is charging, it will get full charging capabilities. When the second car plugs it it will start at 8A, then ramp up to 50% and the first car ramps down to 50%. As one car tapers off, the other will increase so that all available amps are able to be used as needed.
Please note that if your server connection is lost the Load Share group will default to the safe start rate of 6A each.