Vertiv Liebert EXS 80kVA UPS, Руководство пользователя

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Vertiv™ Liebert EXS 80kVA UPS User Manual
1 Overview
UPS module failure
In case of inverter failure and output fuse blowout, the load will automatically transfer to the bypass, and
the output power supply will not be interrupted. In this situation, please contact the local customer service
center of Vertiv for technical support.
(Parallel System)
In the event of a fault in a UPS module, it will automatically exit from the parallel system.
If the system is still capable of providing the required load, the remaining modules will continue to supply
the load with no interruption. If the remaining modules are no longer capable of fulfilling the power
requirements, the load will automatically transfer to the bypass.
Overload
If the inverter is overloaded or the inverter current remains outside the specifications longer than the
specified time, the load will automatically transfer to the bypass without power interruption. If both the
overload and the current are reduced to a level within the specified range, then the load will be transferred
back to the inverter. In case of output short circuit, the load will be transferred to the bypass, and the
inverter will shut down. Five minutes later, the inverter will start up automatically. If the short circuit is
removed at this point, the load will be transferred back to the inverter. The transfer is determined first of all
by the features of the protective device of the system.
In the above two situations, the UPS operator control and display panel will display alarm messages.
(Parallel System)
The control logic system constantly monitors load requirements and controls the power
supplied by each UPS module. In the event that an overload condition is sustained for greater than a
preset time, the load will transfer to the bypass, when the number of active modules is unable to satisfy
load requirements. The load returns to the inverter if the power is reduced to a value that can be sustained
by the number of active modules in the system.
Maintenance bypass
The UPS has a second bypass circuit, i.e. maintenance bypass, which provides a safe working environment
for the engineers to provide regular maintenance or repair to the UPS system and at the same time provide
unregulated mains supply to the loads. The maintenance bypass can be manually selected through the
maintenance bypass switch, and it can be disconnected by turning the switch to OFF.
WARNING: If the UPS system is composed of two or more UPS modules, and when the load
capacity exceeds the single module capacity, do not use the internal maintenance bypass
switch.
1.2.4 UPS Power Supply Switch Configuration
The UPS has four switches: rectifier input switch Q1, bypass input switch Q2, maintenance bypass switch
Q3, output switch Q5.
Figure 1-2 describes the block diagram of the UPS module. The UPS is available in split bypass
configuration (that is, the bypass adopts independent mains input) and common input configuration.
If the system adopts common input configuration, the UPS has copper shorting bar of common input
configuration, and the bypass input switch (Q2) and rectifier input switch (Q1) would be linked together.
If the system adopts split bypass configuration, just remove the copper shorting bar of common input
configuration of the UPS.
During the normal operation of the UPS, except for the maintenance bypass switch Q3, other switches shall
be closed.