Automatic Operations - Liebert 1000kVA Operation & Maintenance Manual

Local Emergency Modules Off (LEMO)
The UPS controls at the SCC include an Emergency Module Off pad (Figure 10, item 12). When
this guarded pad is pressed, the load is automatically transferred to the bypass line and the
module output, battery and input circuit breakers trip open to isolate and shut down all the UPS
modules. Control Power for indicators and alarms remains On.
Remote Emergency Power Off (REPO)
The Remote Emergency Power Off control (REPO) is a switch located remotely from the UPS system.
It will normally be in the same room as the critical load equipment.
The Remote Emergency Power Off switch removes all power to the critical load.
When you trip the Remote Emergency Power Off switch, all UPS circuit breakers are opened, includ-
ing the System Bypass circuit breaker (SBB). All power through the UPS is removed from the
load. You will still have power to the UPS controls, and you may have power to the static switch.
3.5

Automatic Operations

The Liebert Series 610 UPS system is designed to function while unattended by an operator. The sys-
tem control logic monitors the performance of the UPS, the availability of power sources and the cur-
rent required by the critical load.
The system control logic at the SCC:
• Determines what overload conditions can be sustained without a transfer to bypass.
• Initiates an automatic transfer to bypass to sustain an overload.
• Can initiate an automatic retransfer to the UPS after a system overload has been cleared.
• Initiates an automatic transfer to bypass and emergency module shutdown when a specified UPS
fault occurs.
The control logic at each UPS module:
• Determines what overload conditions can be sustained by the module while it is on-line.
• Automatically takes the UPS module off line and initiates an emergency module shutdown when
selected UPS faults occur.
95
Operation