Eaton Power Xpert 9395P-900 Series, Installation And Operation Manual

Page: 24 / 232

Introduction
1-8 Eaton
®
Power Xpert
®
9395P-900 UPS Installation and Operation Manual P-164000501—Rev 09 www.eaton.com/powerquality
1.3.6 Input Output Module Configuration
The UPS can be supplied in an Input Output Module (IOM) configuration without the bypass input connections,
the static switch, and the backfeed protection contactor. This configuration is primarily used in multiple UPS
parallel systems that do not need a bypass for each UPS and use a separate System Bypass Module (SBM) to
provide system bypass capabilities.
1.3.7 Continuous Static Switch
A continuous static switch is used to provide transfer of the load from the inverter to the bypass source in the
event the inverter become unavailable.
1.3.8 Inherent Redundancy
To deliver greater reliability, the Power Xpert 9395P-900 UPS can be configured by an authorized Eaton
Customer Service Engineer for inherent redundancy. When configured, the UPS automatically becomes
redundant if the load is at or below the capacity of the UPMs minus the capacity of one UPM. Under normal
conditions the UPMs in the UPS share the load equally. If one or more UPMs becomes unavailable and the load
is at or below the capacity of remaining UPMs, the remaining UPMs supply the load instead of transferring to
bypass.
If the capacity of the UPMs falls below the redundancy level or the load increases above redundancy level, but
is still able to maintain the load, a loss of redundancy alarm is sounded. If the load exceeds the capacity of
remaining UPMs, the UPS transfers to bypass.
1.3.9 Energy Saver and High Alert Modes
As a subset of Normal mode, Energy Saver mode maximizes efficiency by eliminating unnecessary power
conversion when the commercial power source is within acceptable voltage and frequency limits. In this mode,
the UPS is actively monitoring the critical bus and instantly and seamlessly transitions to double-conversion
mode (inverter online) if a commercial electrical power brownout, blackout, overvoltage, undervoltage, or
out-of-tolerance frequency condition occurs.
In High Alert mode, the unit transfers from Energy Saver mode to double-conversion mode or if in
double-conversion mode remains in double-conversion mode for a default time period of one hour. High Alert
mode allows the user to place the unit in double-conversion mode when outside conditions could cause a
power disturbance. At the completion of the time period, the unit defaults back to Energy Saver mode. If the
High Alert command is received during the time period, the timer will be restarted.
1.3.10 Variable Module Management System and High Alert Modes.
Variable Module Management (VMMS) maintains UPM redundancy and achieves higher efficiencies by
intelligently controlling the UPM’s load level. The efficiency rating for each UPM is highest when loads are
greater than 50% of the system rating. Therefore, shifting the load to fewer UPMs can achieve higher
efficiencies when the UPS load is lighter.
In VMMS mode, the UPS is actively monitoring the critical bus and UPMs are available to assume load in less
then 2 ms to respond to load changes.
NOTE Energy Saver System mode requires the UPS to be factory built with a Continuous
Static Switch (CSS).
NOTE The Variable Module Management System and Energy Saver System modes are
mutually exclusive.
NOTE Variable Module Management System and Energy Saver modes are mutually
exclusive.