Reserve Capacity

The Reserve Capacity is an estimate of how long the vehicle can be driven with no generator output, the headlamps turned on, and minimum electrical load (with most accessories turned off). Reserve Capacity is the maximum amount of time (in minutes) for a fully charged battery, being discharged at a temperature of 27°C (80°F), to reach a terminal voltage of 10.5 Volts. (Other temperatures or current draws, the state of charge, the condition of the battery etc., will all affect how long the battery will actually last when one drives the vehicle and there is no generator output to the battery).