Emerson GXT3, 208V Major Components, Transient Voltage Surge Suppression TVSS and EMI/RFI Filters

Product Description

1.4Major Components

The operating principle of the UPS is illustrated in Figure 6.

Figure 6 Operating principle diagram

Input	Dynamic	Output
	Bypass

L1	TVSS & EMI/
	RFI Filters

Rectifier /

PFC

Inverter L1

DC-to-DC

Converter

L2/N

G

Battery Charger

Battery

L2/N

G

The UPS is composed of utility input, TVSS and EMI/RFI filters, rectifier/PFC, inverter, battery charger, DC-to-DC converter, battery, dynamic bypass and UPS output.

Transient Voltage Surge Suppression (TVSS) and EMI/RFI Filters

The Liebert® GXT3™ has surge protection and filters that protect the connected load from power surges, electromagnetic interference (EMI) and radio frequency interference (RFI). These features can minimize any surges or interference present in the utility power. The filters also prevent surges or interference generated by the UPS from adversely affecting devices connected on the same branch as the UPS.

Rectifier/Power Factor Correction (PFC) Circuit

In normal operation, the Liebert GXT3’s rectifier/power factor correction (PFC) circuit converts utility power to regulated DC power for use by the inverter while ensuring that the wave shape of the input current used by the UPS is near ideal. Extracting this sinewave input current achieves two objectives:

•Efficient power use by the UPS

•Reduced reflected harmonics

This results in cleaner power being available to other devices in the building not being protected by the Liebert GXT3.

Inverter

In normal operation, the Liebert GXT3’s inverter utilizes the DC output of the PFC to produce precise, regulated sine wave AC power. When utility power fails, the inverter receives DC power from the DC-to-DC Converter. In either operation mode, the UPS inverter is online, continuously generating clean, precise, regulated AC output power.

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