DC battery charger
First of all we should know dc battery charger or DC UPS both are same. The function of DC battery charger is to convert AC main supply into DC supply and send to dc load and also its store the dc supply into battery bank and whenever main supply is failed then the stored energy can be reused.
Block diagram for DC battery charger:
S3- selector switch
Q2- charger output isolator
P1 & P2 – charger input voltage & current
K100- earth fault monitor
Q1- charger input MCCB
P0- earth fault ammeter
Q3- battery circuit isolator
P3 & P4 – charger output voltage & current
Q4- battery circuit breaker
A46- dropping diodes
K46- dropping diode shunt contacts
Q5- dc load main isolator
P5 & P6 – battery voltage & current
The main 3phase AC supply is connected to selector switch, and here we can check the 3 phase voltage and current readings. and further its connected to Q1 charger input MCCB. after that 3 phase supply is converted into 1 phase supply by transformer T . and then its connected to rectifier unit for converting AC supply into DC supply. then the output DC voltage and current you can check in P3 & P4 meter. then its connected to Q2 charger output isolator. after that its connected into K100 earth fault monitor and earth fault ammeter for earthing protection. and its further connected to battery circuit isolator here you can check the battery charging current & voltage in P5 & P6 meter.
and its further connected to battery circuit breaker and battery bank. the supply from the Q2 terminal is further connected into dropping diodes for smoothing output. and finally its connected into Q5 dc load main isolator.