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ZY120 1-3kVA User Manual EN rev.08.docx
3. System Description
TVSS & EMI/RFI
Filters
Rectifier/PFC
Inverter
Bypass
DC/DC Converter
Battery Charger
Battery
I/P
O/P
Input
Output
3.1 Transient Voltage Surge Suppression (TVSS) and EMI/FRI Filters
These UPS components provide surge protection and filter both electromagnetic interference
(EMI) and radio frequency interference (RFI). They minimize any surge or interference present
in the utility line and keep the sensitive equipment protected.
3.2 Rectifier/Power Factor Correction (PFC) Circuit
In normal operation, the rectifier/power factor correction (PFC) circuit converts utility AC power
to regulated DC power for use by the inverter while ensuring that the waveform of the input
current used by the UPS is near ideal. Extracting this sinewave input current achieves two
objects:
⚫
The utility power is used as efficiency as possible by the UPS.
⚫
The amount of distortion reflected on the utility is reduced.
This results in cleaner power being available to other devices in the building not being
protected by the UPS.
3.3 Inverter
In normal operation, the inverter utilize the DC output of the power factor correction circuit and
inverters it into precise, regulated sinewave AC power. Upon a utility power failure, the inverter
receives its required energy from the battery through the DC-to-DC converter. In both modes
of operation, the UPS inverter is on-line and continuously generating clean, precise, regulated
AC output power.
3.4 Battery Charger
The battery charger utilizes energy from the utility power and precisely regulates it to
