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3RW4037-2TB04
Siemens 3RW4037-2TB04 available at EU Automation. Get in touch today for a quick price.
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What happens next?
1. Email confirmation
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2. Dedicated Account Manager
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3. Your quote
You will receive a comprehensive quote tailored to your specific needs.
The Siemens 3RW4037-2TB04 is a SIRIUS S2 soft starter designed for controlled starting and stopping of three-phase motors in industrial automation applications. Rated at 63 A, it is suitable for motor outputs up to 30 kW at 400 V and operates across a 200–480 V AC main voltage range with a 24 V AC/DC control supply.
Built for standard motor control tasks, this soft starter helps reduce mechanical stress and electrical load during motor start-up by using thyristor-based control with an integrated bypass contact system. It includes adjustable current limitation, intrinsic device protection, motor overload protection and thermistor motor protection evaluation, making it well suited to pumps, fans, conveyors, compressors and other machinery where smoother acceleration is required.
The 3RW4037-2TB04 features spring-loaded terminals for the auxiliary and control circuit, screw-type terminals for the main current circuit and a compact S2 frame size measuring 55 mm wide, 160 mm high and 170 mm deep. It provides two normally open auxiliary contacts and one changeover contact, with a red fault indication for clear status visibility.
With an operating temperature range of -25 °C to +60 °C, IP20 front protection and suitability for screw or snap-on mounting, the Siemens 3RW4037-2TB04 offers a practical and space-efficient solution for integrating soft-start motor control into industrial panels and automation systems.
Built for standard motor control tasks, this soft starter helps reduce mechanical stress and electrical load during motor start-up by using thyristor-based control with an integrated bypass contact system. It includes adjustable current limitation, intrinsic device protection, motor overload protection and thermistor motor protection evaluation, making it well suited to pumps, fans, conveyors, compressors and other machinery where smoother acceleration is required.
The 3RW4037-2TB04 features spring-loaded terminals for the auxiliary and control circuit, screw-type terminals for the main current circuit and a compact S2 frame size measuring 55 mm wide, 160 mm high and 170 mm deep. It provides two normally open auxiliary contacts and one changeover contact, with a red fault indication for clear status visibility.
With an operating temperature range of -25 °C to +60 °C, IP20 front protection and suitability for screw or snap-on mounting, the Siemens 3RW4037-2TB04 offers a practical and space-efficient solution for integrating soft-start motor control into industrial panels and automation systems.
| Specification | Description |
|---|---|
| Manufacturer | Siemens |
| Part Number | 3RW4037-2TB04 |
| Alternative Part Number | 3RW40372TB04 |
| Product Range | SIRIUS |
| Product Type | Soft starter for standard motor starting applications |
| Frame Size | S2 |
| Rated Operational Current | 63 A at 40 °C |
| Current Rating at 50 °C | 58 A |
| Current Rating at 60 °C | 53 A |
| Motor Power Rating at 400 V | 30 kW at 40 °C in standard circuit |
| Motor Power Rating at 230 V | 18.5 kW at 40 °C in standard circuit |
| UL/CSA Motor Rating at 220/230 V | 20 hp at 50 °C in standard circuit |
| UL/CSA Motor Rating at 460/480 V | 40 hp at 50 °C in standard circuit |
| Operating Voltage | 200 to 480 V AC |
| Operating Frequency | 50 to 60 Hz |
| Control Supply Voltage | 24 V AC/DC |
| Main Circuit Poles | 3 |
| Integrated Bypass Contacts | Yes |
| Thyristor Control | Yes |
| Motor Overload Protection | Integrated |
| Thermistor Motor Protection | Integrated evaluation for thermistor motor protection |
| Adjustable Current Limitation | Yes |
| External Reset Function | Yes |
| Inside-Delta Circuit | No |
| Motor Brake Output | No |
| Rated Insulation Voltage | 600 V |
| Maximum Thyristor Blocking Voltage | 1,600 V |
| Minimum Load | 20% |
| Minimum Adjustable Motor Current | 26 A |
| Continuous Operating Current | 115% of rated operational current at 40 °C |
| Typical Power Loss | 12 W during operation at rated current and 40 °C |
| Fault Indication | Red fault signal display |
| Main Circuit Connection | Screw-type terminals |
| Auxiliary and Control Connection | Spring-loaded terminals |
| Auxiliary Contacts | 2 normally open contacts and 1 changeover contact |
| Auxiliary Contact UL Rating | B300 / R300 |
| Main Conductor Cross-Section, Front Clamping Point | Solid: 2 x 1.5 to 16 mm²; finely stranded with ferrule: 0.75 to 25 mm²; stranded: 0.75 to 35 mm² |
| Main Conductor Cross-Section, Back Clamping Point | Solid: 2 x 1.5 to 16 mm²; finely stranded with ferrule: 1.5 to 25 mm²; stranded: 1.5 to 35 mm² |
| Auxiliary Conductor Cross-Section | Solid: 2 x 0.25 to 2.5 mm²; finely stranded with ferrule: 2 x 0.25 to 1.5 mm² |
| AWG Range for Main Contacts | 18 to 2 AWG at front clamping point; 16 to 2 AWG at back clamping point |
| AWG Range for Auxiliary Contacts | 2 x 24 to 14 AWG |
| Mounting Method | Screw mounting or snap-on mounting |
| Dimensions | 55 mm wide x 160 mm high x 170 mm deep |
| Required Clearance | 60 mm above, 30 mm at the side, 40 mm below |
| Maximum Cable Length | 300 m |
| Operating Temperature | -25 to +60 °C |
| Storage Temperature | -40 to +80 °C |
| Derating Temperature | 40 °C |
| Front Protection Rating | IP20 to IEC 60529 |
| Touch Protection | Finger-safe from the front when contacted vertically |
| Installation Altitude | Up to 5,000 m above sea level |
| Pollution Degree | 3 according to IEC 60947-4-2 |
| Reference Code to EN 61346-2 | Q |
| Reference Code to DIN 40719 / IEC 204-2 / IEC 750 | G |
What type of device is this?
It is a Siemens SIRIUS soft starter designed for standard three-phase motor starting applications. It helps reduce mechanical stress and electrical inrush current during motor start-up compared with direct-on-line starting.
What motor power rating is it suitable for?
The unit is rated for up to 30 kW at 400 V in a standard circuit at 40 °C. It is also rated for 18.5 kW at 230 V under the same standard circuit conditions.
What is the rated operational current?
The rated operational current is 63 A at 40 °C. The rating is reduced to 58 A at 50 °C and 53 A at 60 °C.
What operating voltage range does it use?
The main operating voltage range is 200 to 480 V AC for standard three-phase motor applications, with a rated frequency range of 50 to 60 Hz.
What control voltage is required?
The control supply is 24 V AC/DC. For AC operation, it is suitable for both 50 Hz and 60 Hz control circuits.
Does it include motor protection functions?
Yes. This SIRIUS soft starter includes motor overload protection, intrinsic device protection, thermistor motor protection evaluation and an external reset function.
Does it have an integrated bypass contact system?
Yes. The device includes an integrated bypass contact system, which helps reduce power loss during continuous running after the motor has started.
What terminal types are used?
The main current circuit uses screw-type terminals, while the auxiliary and control circuits use spring-loaded terminals. This configuration suits panel installations where secure wiring and compact connection methods are required.
What are the physical dimensions?
The device is size S2 and measures 55 mm wide, 160 mm high and 170 mm deep. It can be mounted using screw fixing or snap-on mounting.
What ambient temperature range is it designed for?
The operating ambient temperature range is -25 °C to +60 °C. The storage temperature range is -40 °C to +80 °C.
How many auxiliary contacts are included?
The soft starter includes two normally open auxiliary contacts and one changeover contact. The auxiliary contact rating according to UL is B300 / R300.
Is it suitable for inside-delta connection?
No. This unit is not designed for inside-delta circuit use. It is intended for standard circuit connection.
What enclosure protection rating does the front have?
The front of the device is rated IP20 according to IEC 60529 and is finger-safe for vertical contact from the front.
What is the maximum installation altitude?
The maximum installation altitude is 5,000 m above sea level, subject to correct application and installation conditions.
What is the typical power loss during operation?
The typical power loss at operational current during operation is 12 W at 40 °C, helped by the integrated bypass contact system.
- Controlled starting and stopping of three-phase induction motors in industrial machinery
- Reducing mechanical stress on pumps, fans, compressors and conveyors during motor start-up
- Limiting inrush current in 200–480 V AC motor control applications
- Motor control in panels where a compact S2 soft starter is required
- Smooth acceleration of squirrel-cage motors up to 30 kW at 400 V
- Process equipment where adjustable current limitation is needed
- Applications requiring integrated motor overload protection and thermistor evaluation
- Retrofit installations replacing conventional star-delta starters
- Conveyor systems requiring reduced belt shock and smoother load movement
- Pump systems where gradual ramp-up helps reduce pressure surges
- Fan and blower applications requiring lower starting torque than direct-on-line starting
- Compressor motor applications where controlled acceleration can reduce strain on couplings and drive components
- Industrial automation cabinets using 24 V AC/DC control circuits
- Machine building applications requiring auxiliary status contacts for run, bypass and fault signalling
- Motor starter assemblies where screw main terminals and spring-loaded control terminals are preferred
This content has been produced using multiple sources. EU Automation takes no responsibility for the accuracy of this information. Always consult the original equipment manufacturer for the most up to date instructions and information.
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Customer reviews
steve
Daniel
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Tom Higgins did a great job at getting us the part we needed. He saw a concern with the part a verified before shipping.
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