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PB106363A50
Masterpact NW circuit breakers with corrosion protection are designed for use in
industrial environments with high concentrations of sulphur compounds. Examples
include paper mills, oil refineries, steel works and water treatment plants, all of which
produce large quantities of sulphur dioxide (SO2) or hydrogen sulphate (H2S).
Under such conditions, silver-plated parts rapidly turn black due to the formation of
silver sulphate (AgS) on the surface, an insulating material that can lead to abnormal
temperature rise in electrical contacts. This phenomenon can have serious
consequences on all equipment installed inside a switchboard.
Circuit breakers used in such environments generally require frequent maintenance
and therefore a large number of replacement devices on the site. Furthermore,
problems are often encountered even with intensive maintenance.
Masterpact NW circuit breakers with corrosion protection receive special surface
treatment on all parts exposed to corrosion and critical with respect to electrical
continuity. In this way, the availability of electrical power and operating safety are
ensured without special maintenance for the following environmental condition
classes as defined by standard IEC 721-3-3:
3C3 for H2S (concentrations from 2.1 to 7.1 x 10
b
b
-6
)
3C4 for SO2 (concentrations from 4.8 to 14.8 x 10
b
b
-6
).
The Masterpact NW range of power circuit breakers with corrosion protection
offers the following features:
rated current from 800 A to 4000 A
b
b
3 and 4-pole models
b
b
drawout circuit breaker
b
b
operational voltage up to 690 V AC
b
b
Ics breaking capacity of 100 kA at 220/415 V AC
b
b
reverse feed possible
b
b
stored-energy mechanism for instantaneous closing (source coupling).
b
b
3 types of RMS electronic protection
b
b
adjustable long-time settings from 0.4 to 1 In, with fine adjustment via local keypad
b
b
or remote supervisor
electronic functions dedicated to energy management and power-quality analysis.
b
b
The Masterpact NW range complies with the main
standards and certifications:
IEC 60947-1 and 60947-2
b
b
IEC 68230 (damp heat) and IEC 68252 severity level 2 (salt mist)
b
b
IEC 60068-2-42 and IEC 60068-2-43 for corrosive environments:
b
b
SO2 : tested to IEC 60068-2-42 in a 3C4 environment as defined by
v
v
IEC 60721-3-3
H2S: tested to IEC 60068-2-43 in a 3C3 environment as defined IEC 60721-3-3.
v
v
A complete range of electrical accessories and
auxiliaries:
motor mechanism (MCH)
b
b
undervoltage release (MN, MNR)
b
b
shunt trip unit (MX)
b
b
closing release (XF)
b
b
auxiliary contacts (OF)
b
b
low-level indication contacts (SDE, PF, CD, CT, CE and EF)
b
b
electrical closing button (BPFE)
b
b
locking by padlocks and/or keylocks.
b
b
source-changeover systems for 2 or 3 devices
b
b
Maximum safety
The Masterpact NW range with corrosion protection offers the same safety features
as the standard version:
positive contact indication
b
b
high impulse withstand voltage (12 kV)
b
b
suitable for isolation in compliance with IEC 60947-2, as indicated by the
b
b
disconnector symbol on the front face:
Front face insulation class 2, allowing class 2 installations with breaker control
b
b
from outside.
Masterpact NWwith corrosion
protection 800-4000 A
Functions
and characteristics
version: 1.2
207E2510.indd