The requirement of customers varies for the type of equipment being used in terms of DC voltage and load current. The load duty cycle profile keeping in view ampere-hours capacity of the battery, a suitable battery charger is to be selected to maintain smooth continuous stabilized DC power.
The battery chargers are manufactured in different designs as per the application and cost competitiveness. the normal type battery charger is as under:
(i) Manual operated through selector switch controlling the voltage and current used for small receiving station.
(ii) Float cum Boost is one unit and used where the stand by p[ower through battery is not put to use frequently. the mode of charger is automatically stabilized in the event of variation of input voltage as well as load variation and is put to manual mode in the event of charging the battery on the boost through selector switch.
(iii) Float and Boost are two separate battery charger units interlocked with each other placed in one common cabinet. The float charger is automatically controlled to stabilize DC output against AC input variation and variations in the load. It keeps the battery in float conditions plus meets the requirement of regular load. The boost is manually controlled to charge the discharged battery during the failure of power failure. During this situation the battery is disconnected from float charger and connected to boost charger through interlock. The battery charger is automatically controlled through servo system / solid state with DC Output of + 1%. the servo system control has advantage over the solid state by virtue of very low ripple output comparatively and in addition it can be operated manually through selector switch in the event of some defect-taking place in the automatic control, which is not available in solid-state system.
It has following important features: