Figure 6 UPS Module Block Diagram

MULTI-MODULE UPS SYSTEM

CONTROL POWER

Controls

Utility

 

Rectifier/

Input

 

 

Charger

Power

Input

 

CB

Inverter

MBD

Control

Wiring

To SCC

Output

Power

OutputTo SCC

CB

Battery

CB - Circuit Breaker

MBD - Module Battery Disconnect

SCC - System Control Cabinet

UPS Module

The UPS module consists of module controls, a rectifier/charger, an inverter, protective devices, and other acces- sories.

Module Controls: The module control logic monitors performance of the UPS module. The UPS module status is displayed locally and is also sent to the System Control Cabinet.

Rectifier/Charger: The rectifier/charger converts utility power from AC to DC to charge the battery and pro- vide the DC input to the inverter. Its design limits reflected harmonic current distortion to source power and pro- vides low-ripple DC power for charging batteries. Multiple rectifier/chargers can share a common battery plant, if that configuration is preferred for your application.

Inverter: The inverter converts DC power into the precise AC power required to supply a sensitive critical load. The inverter converts DC power into a pulse-width-modulated (PWM)/six-step waveform that is easily filtered into a clean sine wave output. The PWM/stepwave also minimizes the harmonic voltage distortion caused by typical switching power supplies and other non-linear load components used in computers and related electron- ics.

Battery Plant

The battery is used as the alternate source of power to supply DC power to the inverter if the AC supply voltage is outside the acceptable range. The battery supplies power to the inverter until the utility power is restored or until an alternate power source is available. If AC source power is not restored or an alternate power source is not available, the battery can be sized to provide power long enough for an orderly shutdown of the load.

14

Theory of Operation

DISCONTINUED

 

 

PRODUCT

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Liebert Series 600T manual UPS Module, Battery Plant