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A-3
Protection
of
distribution
systems
(AC 220/690 V)
page A-14
Protection
of
motors
(AC 220/690 V)
page A-36
Control and
isolation
using
switch-
disconnectors
page A-56
Protection
of
special
applications
page A-48
Source
changeover
systems
page A-60
Compact NSX devices are equipped with MA or TM
thermal-magnetic trip units or Micrologic 2 / 5 / 6
electronic trip units to provide protection against short-
circuits and overloads for:
distribution systems supplied by transformers
b
distribution systems supplied by engine generator
b
sets
long cables in IT and TN systems.
b
They can be easily installed at all levels in distribution
systems, from the main LV switchboard to the
subdistribution boards and enclosures.
All Compact NSX devices can protect against
insulation faults by adding a Vigi module or Vigirex
relay.
The Compact NSX range includes a number of
versions to protect motor applications:
basic short-circuit protection with MAmagnetic trip
b
units or the electronic Micrologic 1-M version,
combined with an external relay to provide thermal
protection
protection against overloads, short-circuits and
b
phase unbalance or loss with Micrologic 2-M trip units
more complete protection against overloads and
b
VKRUW FLUFXLWV ZLWK DGGLWLRQDO PRWRU VSHFL¿F SURWHFWLRQ
(phase unbalance, locked rotor, underload and long
start) with Micrologic 6 E-M trip units. These versions
also offer communication, metering and operating
assistance.
The exceptional limiting capacity of Compact NSX
circuit breakers automatically provides type-2
coordination with the motor starter, in compliance with
standard IEC 60947-4-1.
Special applications:
The Compact NSX range offers a number of versions
for special protection applications:
service connection to public distribution systems
b
page A-48
nerators
ge
page A-50
industrial control panels
b
page A-52
with:
compliance with international standards
v
IEC 60947-2 and UL 508 / CSA 22-2 N14
compliance with US standard UL 489
v
installation in universal and functional enclosures.
v
16 Hz 2/3 systems
b
page A-53
400 Hz systems
b
page A-54
For all these applications, circuit breakers in the
Compact NSX range offer positive contact indication
and are suitable for isolation in accordance with
standards IEC 60947-1 and 2.
A switch-disconnector version of Compact NSX circuit
breakers is available for circuit control and isolation.
All add-on functions of Compact NSX circuit breakers
may be combined with the basic switch-disconnector
function, including:
earth-leakage protection
b
motor mechanism
b
ammeter, etc.
b
For information on other switch-disconnector ranges,
see the Interpact (offering positive contact indication
and visible break) and Fupact (fusegear) catalogues.
To ensure a continuous supply of power, some
electrical installations are connected to two power
sources:
a normal source
b
a replacement source to supply the installation when
b
the normal source is not available.
Amechanical and/or electrical interlocking system
between two circuit breakers or switch-disconnectors
avoids all risk of parallel connection of the sources
during switching.
A source-changeover system can be:
manual with mechanical device interlocking
b
remote controlled with mechanical and/or electrical
b
device interlocking
automatic by adding a controller to manage
b
switching from one source to the other on the basis of
external parameters.
559E1100.indd
version: 1.0