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2.3 Design Concept
The figure below shows the block diagram of the UPS.
BYPASS
#
INPUT
RECTIFIER INVERTER STATIC SW OUTPUT TO
CRITICAL LOAD
ISO
TXR
CHARGER
# - This shorting link is removed when connected
with separate bypass source.
BATTERIES
The input to the UPS is 230 V, single phase supply. This is converted into DC
power by the rectifier circuit for the inverter. The inverter in turn converts this
DC power into AC for the critical loads.
The batteries are independently charged from the input AC. In the event of
loss of input AC, the batteries takes over and feeds the inverter.
The static switch serves as a dynamic bypass and connects the input /
bypass supply in the event of inverter failure or overload.
