[Dual Float cum Boost charger – Single Battery – Single load]
The Battery Charging equipment comprises of Dual Float cum Boost charger with Single Battery and Single Load configuration.
Each Float cum Boost charger has two modes of operation i) Constant Voltage Float Mode, ii) Constant Voltage / Current Boost Mode (as applicable as per the battery type).
Normally, Both the chargers will be in Float mode to trickle charge the Battery & supply station load thus sharing the total load. During this time, both the float cum Boost chargers and the battery are across the DC load terminals.
During an emergency when AC power fails, the battery supplies the load and discharges to certain extent depending upon duration of emergency and the intensity of the discharge current. When AC power is restored, the battery needs to be boost charged for which operate Float cum Boost charger in its boost mode.
When AC power is restored, the Battery needs to be Boost charged. Under such condition, one charger shall be operated in Float mode to supply the station load & operate another charger in Boost mode for charging the battery either Manually or Automatically depending upon the circuitry logic provided in charger as per customer specification. During this operation of Battery Charger, Battery positive bus & load positive bus will be separated by DC contactor and / or MCCB as applicable.
In this scheme of Battery Charger, either of the Float cum Boost charger can be used for boost charging of battery either Manually or Automatically depending upon the circuitry logic provided in charger as per customer specification, thus implying the redundancy of the Charger but had a limitation for redundancy of Battery.
To overcome on the above, next scheme is Dual Float cum Boost charger – Dual Battery – Single load.