Distributed Bypass Power Wiring Preparation - Eaton Power Xpert Plus 1 Installation And Operation Manual

UPS INSTALLATION PLAN AND UNPACKING
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Power Xpert 9395 UPS (450–550 kVA) Installation and Operation Manual
On all 9395 models that will be fed by a site generator at any time it is recommended to have an "On
Generator" sensing input connected and proven functional. This allows the UPS to optimize its operation
with the generator. This function includes reduced input current and battery current limits, slower walk-in to
ease the load step on the generator initially, and HIGH ALERT mode for ESS and VMMS operation.
HIGH ALERT mode is desired because any loads with a leading power factor will not be seen by the
generator. Rectifier operation will be much softer while on generator thereby increasing overall system
stability.
3.2.4

Distributed Bypass Power Wiring Preparation

Read and understand the following notes while planning and performing the
installation:
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All distributed bypass UPS rectifier inputs must come from one source and all
bypass input feeds must come from one source.
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All UPSs in the distributed bypass system must contain the same number of
UPMs. Mixed UPS kVA ratings are not permitted.
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Distributed bypass UPS input wiring size requirements and output wiring size
requirements from the UPSs to the tie cabinet or distribution panel are the same as
listed in Table 3‐4 on page 3-9 and Table 3‐5 on page 3-10.
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If the load requires a neutral, a bypass source neutral must be provided.
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In the case of parallel Distributed Bypass configurations, wiring for the common
system neutral reference will also be connected to E12 of each module and this
common system neutral reference wiring will be routed to the output switchgear
cabinet and connected to an isolated / ungrounded bus which is common with the
wiring from the E12 terminal of all other paralleled modules of the Distributed
Bypass system.
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DO NOT install both a source neutral and a bonding jumper. See Table 3‐7 for
neutral bonding jumper wire sizes. The bonding jumper must be copper wire.
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Eaton UPS systems are designed to operate with two optional ground schemes.
Both configurations comply with international safety regulations (as seen on the
UPS name plate).
- 1. Internal reference generated through an earth reference. Ground current will
be equal to or less than 5% of the unit rating. This takes the form of a UPS N
bus to ground bond wire. This configuration is confirmed by reviewing the unit's
CTO number.
- 2. Internally generated reference which avoids ground current. By locating the
center reference inside the three phase conductors, the relationship between
the UPS source and the UPS output is maintained. This is an internal UPS
function and requires no additional work on the part of the installer or user. This
configuration is confirmed by reviewing the unit's CTO number.
SINGLE HIGH IMPEDANCE GROUND SOURCE - In North American installations, the neutral conductor from
the high impedance ground source of supply CANNOT be used. DO NOT bond the inverter center point (E12)
to ground: this is an internal UPS function and requires no additional work by the installer or user.
DUAL HIGH IMPEDANCE GROUND SOURCE - In North American installations, the neutral conductor from the
high impedance ground source of supply CANNOT be used. DO NOT bond the inverter center point (E12) to
ground: this is an internal UPS function and requires no additional work by the installer or user. Please
contact the Eaton help desk listed in Chapter 1 for additional guidance regarding dual high impedance
ground sources.
C A U T I O N
C A U T I O N
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164201701 Rev 4