From LEAF Info Center
EVSE is an acronym for Electric Vehicle Supply Equipment. It is also referred to as a Charge Station or Charging Dock, but from a technical standpoint, it is not a charger.
An EVSE connects to grid power and controls the flow of electricity to the J1772 connector. The power to the connector remains off until the EVSE senses, through the use of a pilot signal, that it has been plugged into a compatible vehicle. When the vehicle is sensed, the EVSE will turn on power to the J1772 connector which will supply power to the vehicle's on-board charger. If the vehicle completes charging or is unplugged, the EVSE shuts off power to the J1772 connector as a safety precaution.
EVSEs use alternating current electricity with a variety of voltages and amperages. Those sold for use in the United States are designed for either 110 to 120 volts (called 120v) or 220 to 240 volts (called 240v). 120v EVSEs are usually plugged into a standard 15 or 20 amp wall outlet. They provide relatively slow charging, which Nissan refers to as trickle charging. 240v EVSEs are usually permanently mounted on a wall or pedestal, and in most cases are directly connected to house wiring with no wall plug. They require a dedicated 240 volt circuit capable of supplying at least 20 amps of current, though many require 40 amps. Note that a typical 240v dryer circuit supplies 30 amps, so could not be used for a 40 amp EVSE.
Nissan quotes EVSE charging rates in terms of the time required to charge the LEAF from the first "Battery Low" warning to 100% charged. This simplifies matters because it is independent of temperature, types of roads, or driving styles. Their figures are approximately 7 hours for a 240v EVSE and approximately 21 hours for a 120v EVSE. These numbers can be misleading, however, because in most cases you will be recharging your car before you see the "Battery Low" warning, and you may well decide to charge it to only 80% in order to maximize battery life. A different way to think of the charging rate is in terms of the number of miles you can drive for each hour of charging, so long as we remember that this is affected by temperature, roads, and driving style. Using a range of 60 to 100 miles, Nissan's figures map to about 3 to 5 miles for each hour of 120v charging, and about 9 to 14 miles for each hour of 240v charging. Note that in theory a higher amperage EVSE should allow the car to charge more rapidly, but the charging rate is currently limited by the charger built into the LEAF.
Programming Charge Times
Certain EVSE models can be programmed to delay charging until lower electric rates are in effect. The Nissan LEAF itself also has the ability to delay charging until a pre-programmed time even if the EVSE does not have that feature.
EVSE Included With the Vehicle
Nissan supplies a 120v EVSE with the car. It resembles an extension cord with the EVSE electronics in a box near where it is plugged in to the wall. Nissan indicates that it should be used on a 20 amp dedicated circuit, but it will not overload a 15 amp circuit so long as nothing else is being powered by that circuit.
Nissan Installed EVSE
The 240v EVSE that Nissan is installing if you purchase it through them is the Aerovironment EVSE. It requires a 40 amp circuit.
The 240v EVSE that EV Project participants will receive free of charge is the BLINK EVSE. This EVSE has many features that will allow the EV Project to track charging habits and energy usage via it's wireless data connection.