Liebert 610 manual Load on Bypass, Circuit breaker abbreviations, Abbreviation Circuit Breaker

Operation

3.3Modes of Operation

This section illustrates the flow of power through circuit breakers, switches and UPS components dur- ing various modes of operation. The same modes of operation apply to all configurations of the Liebert Series 610 UPS. Highlighted (thick) lines in the diagrams indicate power flow and power availability.

These illustrations show a three-breaker maintenance bypass because it is commonly used. Your installation may have a two-breaker, three-breaker or four-breaker maintenance bypass or none at all.

These illustrations do not show an alternate power source (generator) and automatic transfer switch (external to the UPS) that might be present at your installation.

Table 7 below lists abbreviations for circuit breakers used in this manual.

Table 7	Circuit breaker abbreviations
Abbreviation		Circuit Breaker
BFB		Bypass Feeder Breaker
BIB		Bypass Input Breaker
MBB		Maintenance Bypass Breaker
MBD		Module Battery Disconnect
MIB		Maintenance Isolation Breaker
RIB		Rectifier Input Breaker

3.3.1Load on Bypass

Load on Bypass, with the UPS not available, is shown in Figure 41. The UPS system could be in this mode of operation during either initial start-up or UPS system shutdown and isolation for maintenance.

NOTE

When the critical load is being supplied power from the bypass line, it is exposed to utility power disturbances.

Figure 41 Load on bypass (UPS not available)

THREE BREAKER MAINTENANCE BYPASS SWITCHBOARD

BFB	MBB
	Critical
	Load
	AC Output
BIB	MIB

UPS MODULE

Static

Switch

Disconnects

Static

Bypass

Switch

Bypass CB

CONTROL POWER
Controls
RIB
Rectifier/	Inverter
Charger
INPUT
CB

MAIN INPUT

SWITCHGEAR

MBD

OUTPUT

CB

Battery

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