Eaton Power Xpert 9395 550/275 Installation And Operation Manual page 27

Introduction
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 ESS mode. If the High Alert command is received
during the time period, the timer will be restarted.
1 1 . . 2 2 . . 1 1 1 1 H H a a r r m m o o n n i i c c R R e e d d u u c c t t i i o o n n S S y y s s t t e e m m ( ( H H R R S S ) )
The Harmonic Reduction system mode of the 9395 UPS allows the UPS to actively reduce the input Total
Demand Distortion (TDD) and increase the input power factor while maintaining high efficiency operation in
ESS mode. The UPS uses one of its UPMs to perform this active harmonic cancellation.
HRS mode uses an extra set of sensors (CTs) on the output bus of the unit. These sensors measure the
harmonics created by loads attached to the UPS output and the system actively reduces these harmonics.
NOTE
The system must be in ESS mode to activate HRS mode. In HRS mode, the inverter is ON, the rectifier is OFF
and the output contactor is CLOSED.
HRS is a normal operating mode, not an alarm condition. The NORMAL light appears on the front of the UPS.
1 1 . . 2 2 . . 1 1 2 2 V V a a r r i i a a b b l l e e M M o o d d u u l l e e M M a a n n a a g g e e m m e e n n t t S S y y s s t t e e m m a a n n d d H H i i g g h h A A l l e e r r t t M M o o d d e e s s
NOTE
The Variable Module Management System (VMMS) mode maintains UPM redundancy and achieves higher
efficiencies by intelligently controlling the UPMs 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
than 2 ms to respond to load changes.
The VMMS feature has three configurable modes of operation: Online mode, Online mode with VMMS, and
High Alert mode. All modes are selectable from the front panel.
VMMS mode supports both distributed bypass and SBM parallel configurations.
In High Alert mode, all idle UPMs go online for one hour. At the completion of the hour, the UPS defaults back
to VMMS mode. If the High Alert command is received during the one hour, the one hour timer will be
restarted.
1 1 . . 2 2 . . 1 1 3 3 M M o o n n i i t t o o r r i i n n g g a a n n d d C C o o m m m m u u n n i i c c a a t t i i o o n n
The UPS system can be further enhanced by adding optional accessories such as a Remote Emergency Power-
off (REPO) control, RMP II, SCM II, RIM II, or X-Slot communication cards. See
Chapter 5 Installing Options and Accessories
• Remote Monitor Panel II (RMP II) – An optional RMP II contains backlit status indicators and a local horn,
allowing monitoring of the operational status and alarm condition of the UPS from virtually any location
within the facility.
• Relay Interface Module II (RIM II) – An optional RIM II uses relay contact closures to indicate the UPS
operating status and alarm condition.
• Supervisory Contact Module II (SCM II) – An optional SCM II establishes an interface between the UPS
system equipment and the customer's monitor.
6 Eaton Power Xpert 9395 UPS Installation and Operation Manual 164201716—Rev 14
Total Demand Distortion as defined by IEEE 519-1992 is the total root-sum-square
harmonic current distortion, in percent, of the maximum demand load current (the
nameplate rating of a fully rated UPS).
The Variable Module Management System and Energy Saver System modes are
mutually exclusive.
for additional information.