Major Internal Components And Operating Principle - Vertiv Liebert EXS Installer/User Manual

1.4 Major Internal Components and Operating Principle

The UPS is composed the components described in Figure 1.3 on the facing page. Table 1.2 below,
describes the operation of various circuits through the components.
Table 1.2 Major Component Operation
Component Operation/Function
Transient Voltage
Surge Provide surge protection. Filter electromagnetic interference (EMI) and radio frequency interference (RFI).
Suppression Minimize any surges or interference present in the utility line and protect the sensitive equipment even when on
(TVSS) and internal bypass power.
EMI/RFI Filters
Rectifier/Power In normal operation, converts utility AC power to regulated DC power for use by the inverter while ensuring that
Factor the wave shape of the input current used by the UPS is near ideal. Extracting this sine-wave input current
Correction (PFC) ensures efficient use of utility power and reduces distortion reflected on the utility making cleaner power
Circuit available to devices that are not protected by the UPS.
In normal operation, inverts the DC output of the power-factor-correction circuit into precise, regulated sine-
wave AC power. When utility power fails, the inverter receives energy from the batteries through the rectifier. In
Inverter
both Normal mode and Bypass mode, the UPS inverter remains on-line, generating clean, precise, regulated AC-
output power.
When the UPS is connected to utility power and the rectifier is operating, the battery charger regulates energy
DC-DC Charger
output from the rectifier/PFC to continuously recharge the batteries.
Static Bypass In the event of an output overload, over-temperature condition, or other failure, the switch automatically
Switch transfers connected equipment to bypass power.
Up to 4 strings of long-life, valve-regulated, non-spillable, lead-acid batteries depending on back-up run-time
requirements. See Table 7.3 on page 55, for approximate run times.
Batteries
NOTE: To maintain battery design life, operate the UPS in an ambient temperature of 68°F to 77°F (20°C
to 25°C).
Maintenance
Breaker electrically isolates the UPS and internal batteries for maintenance.
Bypass
6
Vertiv | Liebert® EXS™ Installer/User Guide