- Eaton UPS User's Guide

Eaton 9170
+
UPS (3–18 kVA) User's Guide S 164201393 Rev E www.eaton.com/powerquality
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Chapter 1 Introduction
The Eaton
®
9170
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uninterruptible power system (UPS) is a modular UPS
that contains battery modules and power control modules (referred to as
power modules). These modules plug into a rack cabinet structure
containing additional control, communication, and display functions that
enable integrated control of all power modules. The UPS is housed in a
single cabinet, with extra battery capacity housed in auxiliary battery
cabinets.
The pluggable power modules can be removed and replaced
(hot-swapped) without powering the UPS down if the UPS has sufficient
redundant capacity. Battery modules may also be hot-swapped for
maintenance. Power control circuitry in the cabinet senses problems in
power modules, and automatically transfers control and load to the
remaining power modules.
All power modules share the load requirements equally. For example,
three power modules are capable of supplying a total of 9 kVA. If a load
requires only 4.5 kVA, each power module supplies 1.5 kVA to the
output. If one power module is removed or for some reason fails, each
of the two remaining power modules would supply half of the load, or
2.25 kVA. In other words, redundancy exists when the load can be
supplied by less than all of the installed power modules.
The UPS can be configured with up to seven power and/or optional
battery charger modules; its output is limited such that an excess
number of power modules allow the failure of one or more modules
without causing the UPS to lose any functionality.
To permit UPS removal from the power path while maintaining power to
the loads, an external bypass switch is required. This switch is optional
but recommended for system serviceability.