Eaton Power Xpert 9395P, User And Installation Manual

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P-164000476
9395P 500kVA / 600 kVA 4
Revision 002 User’s and Installation Guide
1.2.6 Distributed Bypass System
There are two types of redundancy: UPS based (based on the number of UPSs) and UPM based (based
on the number of UPMs). Each UPS can contain one to three UPMs.
A distributed bypass UPS system with two to five UPS units can be installed to provide a capacity and/
or redundant system. This load sharing system provides more capacity than a single UPS, and can
provide redundancy, depending on the load and configuration. In addition, when one UPM or UPS is
taken out of service for maintenance or is not operating properly, a redundant UPM or UPS continues
to supply uninterrupted power to the critical load. An Eaton HotSync® Controller Area Network (CAN)
provides connectivity and operational mode control. The distributed bypass system consists of two to
five UPS units each with a CAN card (for paralleling the UPSs), and a customer-supplied tie cabinet or
load distribution panel to act as a tie point.
The tie cabinet must contain Module Output Breakers (MOBs) with dual auxiliary contacts for control
of the system. Without dual auxiliary MOBs, UPSs are not allowed to go to bypass individually during
servicing. All UPSs will go to bypass instead of just the UPS needing service, decreasing critical load
protection. With dual auxiliary MOBs, one UPS can be bypassed while the remaining UPSs support the
load as long as the remaining UPMs have the capacity to do so.
1.2.7 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.
1.2.8 Inherent redundancy
To deliver greater reliability, the Eaton 9395P 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.
1.2.9 Energy Saver and High Alert modes
NOTE
The Variable Module Management System and Energy Saver System modes are mutually
exclusive.
Energy Saver mode allows the UPS to operate in Bypass mode. In this mode, the UPS is operating on
bypass, with the UPMs in standby, ready to automatically transfer to Normal mode 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 Normal mode
(inverter online) or if in Normal mode remains in Normal mode for a default time period of one hour. The
High Alert mode time period is configurable by an Eaton Customer Service Engineer. The High Alert
mode allows the user to place the unit online with full protection when outside conditions could cause