This is an example of an Automatic Control System in which the battery provides information about its actual condition to the charger which compares the actual condition with the desired condition and generates an error signal which is used to initiate control actions to bring the actual condition into line with the desired condition. The control signals form part of a Feedback Loop which provides automatic compensation to keep the battery within its desired operating parameters. It does not require any user intervention. Some form of automatic control system is an essential part of all BMS