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SIRIUS System Manual
GWA 4NEB 430 0999-02b
8-1
8
3RW3 semiconductor motor control unit
(soft starter)
Section
Subject
Page
8.1
Specifications/regulations/approvals
8-3
8.2
Device description
8-5
8.2.1
Physical principles
8-6
8.2.2
General device description
8-10
8.2.3
Comparison of the 3RW3 semiconductor motor cont-
rol unit (soft starter) with the SIKOSTART 3RW22
motor control units
8-14
8.2.4
Comparison of the 3RW3 semiconductor motor cont-
rol unit (soft starter) with the 3RA star-delta combina-
tion
8-16
8.2.5
Notes on configuration
8-16
8.3
Application and use
8-18
8.3.1
Areas of application and criteria for selection
8-18
8.3.2
Installation guidelines
8-18
8.3.3
Overview tables: correction factors
8-21
8.3.3.1
3RW30/31 soft starters in a stand-alone installation
8-21
8.3.3.2
3RW30/31 soft starters in combination with the 3RV1
circuit breaker
8-22
8.3.3.3
Combining the 3RT contactor with the 3RU1 thermal
overload
relay and 3RW3 soft starter
8-24
8.3.3.4
Combining the 3RT contactor with the 3RB10 electro-
nic overload relay and 3RW3 soft starter
8-26
8.3.4
Circuit examples
8-29
8.3.5
Commissioning
8-30