Block Diagram - FSP Technology EP 1000 Series Specification

2 Block Diagram

The Block diagram of Vesta series (refer to Figure S-1) is divided into the following parts:
2.1 Main Relay ( MAI N-RY) :
It's to switch the UPS between line mode and battery mode.
2.2 Boost Relay ( BOOST-RY) :
At line mode, this is a switch used to boost UPS output voltage 18% when the utility
voltage is under line boost activated point. (Refer to Boost activated point table in
P.4)
Relay OFF: line voltage is normal
Relay ON: line voltage is under line boost activated point.
2.3 Buck Relay:
At line mode, this is a switch used to lower UPS output voltage 15% when the utility
voltage is over line buck activated point. (Refer to Buck activated point table in P.4)
Relay OFF: line voltage is normal
Relay ON: line voltage is over line buck activated point
2.4 Main Transformer ( MAI N TX) :
The Main transformer has three functions:
2.4.1 I nverter Transformer
It provides voltage to UPS output and performs a full-bridge transformer
when UPS is at battery mode.
2.4.2 Boost/ Buck
The output coils have an output ratio. Thus the output voltage at boost mode is
given by (Boost Relay ON):
V = V
OUT
The Buck relay is ON when the utility voltage is beyond line buck activated point.
It can lower 15% of input voltage:
V = V
OUT
2.4.3 Charger:
The battery is charged by the mains through transformer and full-bridge
inverter.
2.5 Line Sense
The MCU detect the mains by input voltage and frequency signals converted from
the amplifier.
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* 1.18
IN
* 0.85
IN
Rev. A