Swansons 1K, User Manual

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18
5. UPS Operation Under Various Conditions
5.1. UPS System Block Diagram
Figure 5.1
Figure 5.1 illustrates the True On-Line Double Conversion architecture of the
UPS system. The major modules consist of:
1) An AC-to-DC power converter (rectifier) with PFC control circuit
2) A DC-to-AC high frequency inverter
3) An intelligent battery charger
4) A bank of stationary, maintenance-free batteries
5) A DC-to-DC push/pull converter control circuit
6) A static bypass loop
7) Input and output EMI filters
The table below provides a summary of the UPS operating modes under
various utility AC power source and battery conditions.
19
Utility Condition UPS Operating Mode LEDs
Normal
Working power starts after
approximately 5 seconds, LEDs on the
panel will blink and fans will start. Press
the ON button
for 1-5 seconds. The
UPS starts up normally.
、 、
and
LEDs
remain lit
Abnormal (under or
over voltage or
absent)
Rectifier and charger stop operating.
Battery discharges via DC-DC boost
circuit and supplies Inverter. Loads
continue to receive supply from
Inverter. Alarm buzzer beeps. UPS now
in battery mode.
LED off, LED
illuminated
Utility abnormal or
absent, or battery
voltage low
Rectifier and charger stop operating.
Battery discharges via DC-DC boost
circuit and supplies Inverter. Alarm
buzzer beeps quickly, indicating battery
power low and Inverter may stop
supplying soon.
LED off, and
LEDs illuminated
Sections 5.2-5.7 below provide detailed descriptions of the UPS operating modes.
5.2. When Utility is Normal
The operating mode of the UPS under normal utility conditions is illustrated as
follows.
RECTIFIER
AC/DC CONVERTER
DC/DC CONVERTER INVERTER
STATIC SWITCH
(SSM)
CHARGER BATTERY
O/P
OUTPUT
UTILITY
Fig 5.2
When the utility is normal the AC source is rectified to DC and fed into the charger
to charge the batteries and partially fed into the inverter. The inverter reverts the
DC to a cleaned and pure AC to supply energy to the load connected. The
、
、
and LEDs shine
.