3.4.4Automatic Module Off-Line

For specified UPS module faults, the control logic will initiate an automatic isolation and shutdown of the UPS module. In the Module Off-Line mode the output, battery (MBD), and input circuit breakers are open. If the UPS system was operating in the redundant mode when the module was taken off-line, the critical load will remain on the UPS system. If the UPS system was operating in the non-redundant mode, an automatic transfer to bypass will be initiated. Note that the bypass line is usually not available during Low Battery Shutdown. One Module Off-Line is illustrated in Figure 52.

The following UPS module faults will initiate an automatic Module Off-Line:

DC Over-Voltage Shutdown

Hardware Shutdown

Inverter Fault

Low-Battery Shutdown

Overload Shutdown

Over-Temperature Timeout

Rectifier Fuse Blown

Reverse Power

Refer to Table 1 for more information regarding these alarm messages.

3.4.5Automatic Emergency Modules Off

For the specified UPS system fault, the control logic will initiate an automatic transfer to bypass followed imme- diately by a shutdown and isolation of the UPS system. In the Emergency Modules Off mode the output, battery (MBD), and input circuit breakers at each UPS module are open. The System Bypass Breaker (SBB) will be closed if the bypass line is available. Emergency Modules Off is illustrated in Figure 54.

The following UPS system fault will initiate an automatic Emergency Modules Off:

Output Over Voltage

Refer to Table 1 for more information regarding alarm messages.

NOTE

A load transfer to the bypass line will be completed whenever an automatic transfer to bypass is initiated and the bypass line is available. If the OK to Transfer condition is present, the load transfer will be uninterrupted. If the Static Switch Unable alarm message is present for any reason, the automatic transfer will be interrupted for 40 to 120 milliseconds. Because of the reliability of the UPS components, an interrupted load transfer is a very unlikely occurrence.

Your installation may include a Remote Emergency Power Off mode that can be initiated automatically by a contact closure in the critical load equipment. Refer to 3.2.8 - Emergency Power Off.

Operation 105

DISCONTINUED

PRODUCT

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Liebert Series 600T manual Automatic Module Off-Line, Automatic Emergency Modules Off