Eaton Power Xpert 9395P 250 kVA, Руководство пользователя и инструкция по установке

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6.2.4 Variable Module Management System
NOTE
VMMS and ESS modes are mutually exclusive. If VMMS mode is enabled, ESS mode is
disabled.
In VMMS mode, the UPS operates as a traditional double-conversion UPS. However, the UPS will
selectively shift the load to fewer UPMs based on the required load in order to force the remaining
UPMs to carry a higher load. The efficiency rating for each UPM is highest when loads are greater than
50% of the UPM rating. Therefore, with multiple UPMs, a UPS can achieve higher efficiencies for
lighter loads.
When a UPM is inactivated by VMMS mode, the UPM will stop gating the inverter and rectifier and
keep the output contactor closed in order to maintain voltage match and phase lock to the critical bus.
In this mode the UPS actively monitors the critical bus, keeping the UPM input contactor closed in
order to keep the DC link primed (through the rectifier diodes) and also to allow the UPM to
immediately return to active mode in the event of a disturbance or load step on the critical bus.
VMMS limits the maximum power available from a UPM when in VMMS mode. The default setting is
80% of the UPM full power rating. If the limit is exceeded, additional UPMs are activated to take on the
increased load. The VMMS redundancy setting sets the number of redundant UPMs that the customer
requires. Both the VMMS UPM load limit and UPM redundancy are user-configurable.
In High Alert mode, the UPS defaults to double-conversion Online mode and all UPMs go active for one
hour (user-configurable). At the end of the hour, the UPS defaults back to VMMS mode. If the High
Alert mode is reactivated during the one hour, the one hour timer will be restarted.
6.2.5 Energy Saver System (ESS)
NOTE
VMMS and ESS modes are mutually exclusive. If ESS mode is enabled, VMMS mode is
disabled.
When the UPS is operating in Energy Saver System, the bypass source supplies the commercial AC
power to the load directly through the static switch. Some power line filtering and transient protection
is provided to the load but no active power conditioning or battery support is available. All power
converters are off and are in the ready state (in case a forward transfer is needed). During this mode,
the output contactor is closed and the link is maintained through the diode bridge. Figure 6-4 shows
the path of electrical power through the UPS system when operating in Energy Saver System.
9395P 250 kVA / 275 kVA / 300 kVA
User’s and Installation Guide