Siemens 3RW3038-1BB14 SIRIUS Soft Starter S2 72A 37kW 200-480V AC

The Siemens 3RW3038-1BB14 is a SIRIUS series soft starter, size S2, rated at 72 A and 37 kW at 400 V (40 °C). It provides controlled motor starting and stopping for three-phase AC motors, with an integrated bypass contact system and screw terminals for main and auxiliary circuits.

Technical specifications:

• MLFB: 3RW3038-1BB14
• Manufacturer: Siemens
• Product line: SIRIUS
• Product type: Soft starter
• Size: S2
• Operational current at 40 °C: 72 A
• Operational current at 50 °C: 62 A
• Operational current at 60 °C: 60 A
• Rated power at 400 V (40 °C, standard circuit): 37 kW
• Rated power at 230 V (40 °C, standard circuit): 22 kW
• UL rating at 460/480 V: 40 hp
• Operating voltage: 200-480 V AC
• Control supply voltage: 110-230 V AC/DC
• Operating frequency: 50-60 Hz
• Insulation voltage: 600 V
• Thyristor blocking voltage (max): 1600 V
• Number of main circuit poles: 3
• Auxiliary contacts: 1 NO
• Terminal type: Screw terminals (main and auxiliary)
• IP rating (front): IP20, finger-safe per IEC 60529
• Dimensions (W x H x D): 55 x 160 x 170 mm
• Mounting: Screw and snap-on, vertical surface +/- 10° rotatable and tiltable
• Operating temperature: -25 to +60 °C
• Storage temperature: -40 to +80 °C
• Installation altitude: up to 5000 m
• Degree of pollution: 3 per IEC 60947-4-2
• Power loss at 40 °C (typical): 15 W

Features and benefits:

• Integrated bypass contact system reduces heat dissipation during normal operation.
• Thyristor-based power electronics enable smooth, stepless motor acceleration.
• Wide control supply voltage range (110-230 V AC/DC) simplifies integration into existing control panels.
• Broad operating voltage range (200-480 V) supports both European and North American motor systems.
• Finger-safe IP20 front protection reduces installation risk in open panels.
• Continuous operating current rated at 115% of Ie at 40 °C allows for sustained higher-load operation.

Applications:

• Controlled starting of three-phase induction motors in pump and fan installations.
• Conveyor and compressor motor soft-start applications requiring reduced mechanical stress.
• Industrial machinery requiring smooth ramp-up to minimize current surge on supply networks.
• Motor starting in environments up to 5000 m altitude where derating is required.

Compliant with IEC 60947-4-2. Part of the Siemens SIRIUS range.

Also known as: Siemens 3RW3038-1BB14, SIRIUS 3RW30 soft starter 72A.