Eaton Power Xpert 9395 UPS Installation and Operation Manual 164201716—Rev 13
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The Eaton 9395 UPS is a continuous-duty, solid–state, transformerless (at 480 Vac), three-phase, true online
system that provides conditioned and uninterruptible AC power to the UPS system's output and critical load.
The basic system consists of a rectifier, battery converter, inverter, monitoring/operation control panel,
integrated communication server, and digital signal processor (DSP) logic.
shows the main elements
of the UPS system.
Figure 48. Main Elements of the UPS System
Output
Contactor
K3
Battery
Battery
Breaker
Battery
Converter
Input
Contactor
K1
AC Input to
Rectifier/
Charger
AC Input to
Bypass
Backfeed
Protection
Contactor
K5
Power Module
Inverter
Rectifier
Digital
Metering
Static
Switch
AC Output
to Critical
Load
UPS Cabinet
Battery
Contactor
K2
Battery Cabinet or
Battery String
Input
Breaker
CB1
(optional)
NOTE
On a UPS configured as an Input Output Module (IOM), the bypass input, static switch, and backfeed protection contactor (K5) are not present.
If utility power is interrupted or falls outside the parameters specified in
the
UPS uses a
backup battery supply
to maintain power to the critical load for a specified period of time or until the
utility power returns. For extended power outages, the UPS allows you to either transfer to an alternative
power system (such as a generator) or shut down your critical load in an orderly manner.
The emergency bypass consists of a continuous-duty static switch and backfeed protection contactor K5. The
backfeed protection contactor is located in series with the static switch. For manual transfers to bypass, the
static switch is also used. The static switch is armed and ready during both types of transfers.
