6
Chapter 3 Operation Modes
When the utility AC power fails or unstable voltage occurs, the batteries will instantly
provide DC power to keep continuous operation. Hence, the UPS output will not be
interrupted.
3.3 Reserve AC Supply Mode (Single)
RECTIFIER INPUT
RESERVE
MAINS
BREAKER
RESERVE INPUT
BREAKER
MANUAL BYPASS
BREAKER
OUTPUT
BREAKER
BATTERY BANK
Power Flow
LOAD
STATIC SWITCH
INVERTER
RECTIFIER
Power Flow
Power Flow
Power Flow
Figure 3-3: Reserve AC Power Supply Mode Block Diagram_ Single Unit
When the inverter encounters abnormal situations such as over temperature, long-
time overload, output short circuit, abnormal output voltage and exhausted battery,
the inverter will automatically shut down itself for self-protection. Meanwhile, if the
reserve AC power is normal, the static switch will switch to the reserve AC power
to supply power to the loads without any interruption of power supply. After the
abnormal situations mentioned above are eliminated, the static switch will switch
back to the main AC source (see
Figure 3-3
).
3.4 Maintenance Bypass Mode (Single)
RECTIFIER INPUT
RESERVE
MAINS
BREAKER
RESERVE INPUT
BREAKER
MANUAL BYPASS
BREAKER
OUTPUT
BREAKER
BATTERY BANK
Power Flow
LOAD
STATIC SWITCH
INVERTER
RECTIFIER
Power Flow
Power Flow
Figure 3-4: Maintenance Bypass Mode Block Diagram_ Single Unit
