Chapter 7 - 1 +1 Parallel System; Generality; Introduction - Emerson 7400M Series User Manual

Chapter 7 – 1 + N Parallel System
7.1

Generality

7.1.1 Introduction

02/02
The 7400-M Series uninterruptible power supply (UPS) system may
operate in 1+1 configuration to gain more reliability supplying the
load, more power than a single module, more flexibility during
maintenance of the system.
A system 1+N is made by maximum six single modules 7400-M, each
equipped with option Parallel Kit
The modules have outputs connected in parallel.
The system may be set as
1 redundant
1 full power (this is allowed from release 14105197 with software
Version 04.1; High Voltage Interface Board (# 100208123000)
System capacity
For correct operation the modules that are to be paralleled must have
same power rating and same release (hardware and software).
The paralleled modules share currents to load equally.
Redundant power
The redundant system capacity is the ability to supply the load with
the same features as a single module when one of the two modules in
parallel is not operating (for maintenance or failure): the redundant
power of the system is the same of the rated power of a single
module.
Total power (full power capacity)
The power system capacity is the ability to supply the load with the
paralleled modules operating in parallel with same features than the
single module:.
In case of failure of a module load continuity may not be guaranteed.
Overload capacity
The overload capacity of the system is the ability to supply the load
with the two modules operating In parallel when there is an overload
in output without commutating load on bypass: the overload capacity
of the system is twice the overload capacity of a single module.
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