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Siemens 3RW4037-1BB14

SIRIUS SOFT STARTER, S2, 63A, 30KW/400V, 40 DEGR., AC 200-480V
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  • 2 Year Warranty
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Part Number3RW4037-1BB14
Model #3RW40371BB14
Warranty2 Year
CategorySoft start module
Operating current63A at 40 °C / rated value, 58A at 50 °C / rated value, 53A at 60 °C / rated value
Frequency 50/60 Hz
Operating voltage200-480 V
Control supply voltage110-230 250V/at 50 Hz/ AC
Size of the engine control deviceS2
MountingScrew and snap-on mounting
Installation altitude 5000 M
Max cable length300m
NO contacts2
Change-over switches1
Ambient temperature -25 … +60°C

Our Repair Services

MRO Electric repairs CNCs, PLCs, Servo/Spindle Drives, Motors, Amplifiers, VFDs, HMIs, and more, most of which can be repaired in only 3-5 days.

Repair Benefits

MRO can restore your failed 3RW4037-1BB14 to remanufactured condition and save you up to 75% compared to buying new. We offer standard repair pricing to ensure you the best value for your repair.

Our certified technicians use rigorous testing procedures to ensure your parts are restored to fully functioning condition. Our team proudly stands behind all repairs by providing a minimum 2-year warranty.

Our technicians have vast experience with most manufacturers and models. In addition to this 3RW4037-1BB14 we also repair a wide range of other Siemens products, so if you don’t see the model you need, please contact us.

Core Exchange

If you are interested in getting credit for your faulty 3RW4037-1BB14, just let us know, and we can issue you an RMA to send it in as an exchange. Our exchange program provides you with savings and keeps us stocked for the next time you need anything.

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Ask about exchanging your faulty 3RW4037-1BB14 for credit when ordering from MRO Electric

MRO Electric provides a 2-year warranty on every item we sell and repair. We stand behind all of our products and guarantee them for the full 2 years. If there is an issue with any of our products within the warranty period, we will evaluate the unit and repair or replace it under warranty.

Siemens 3RW4037-1BB14 Overview

Siemens 3RW4037-1BB14 Sirius Soft Starter: Enhancing Control and Efficiency

The Siemens 3RW4037-1BB14 is a member of the Sirius soft starter product line, designed to provide efficient and controlled acceleration of three-phase motors in standard applications. Let's delve into the key features and specifications of this versatile soft starter.

Product Overview:

  • Brand: Siemens Sirius
  • Type: Soft Starter
  • Model: 3RW4037-1BB14

Functional Features:

  1. Integrated Bridging Contact System: The soft starter comes equipped with an integrated bridging contact system, enhancing its efficiency in motor control applications.
  2. Thyristors: Utilizing thyristors, the device ensures precise and reliable control over motor acceleration, contributing to optimal performance.
  3. Device Protection: The soft starter includes intrinsic device protection, safeguarding the internal components and ensuring longevity.
  4. Motor Overload Protection: With built-in motor overload protection, the 3RW4037-1BB14 prevents damage to the motor by monitoring and responding to overload conditions.
  5. Adjustable Current Limitation: Users can fine-tune the current limitation settings, providing flexibility and customization for diverse applications.
  6. Inside-Delta Circuit: This soft starter does not include an inside-delta circuit, a configuration often used in certain motor starting scenarios.

Power Electronics:

  • Operating Current: The device operates at various temperatures, with a rated current of 63A at 40°C, 58A at 50°C, and 53A at 60°C.
  • Emitted Mechanical Power: At standard switching and 40°C, the soft starter can handle a rated mechanical power of 30,000W for three-phase squirrel cage motors at 400V.
  • Operating Frequency: With a rated frequency of 50-60Hz, the 3RW4037-1BB14 is suitable for a broad range of applications.
  • Operating Voltage: It supports an operating voltage range of 200-480V with standard circuitry.

Control Electronics:

  • Voltage Type: The control electronics operate on both AC and DC supply voltages.
  • Control Supply Voltage Frequency: The soft starter supports frequencies of 50Hz and 60Hz for AC supply voltage.
  • Control Supply Voltage Range: The control supply voltage for AC ranges from 110V to 230V at both 50Hz and 60Hz. For DC, the range is also 110V to 230V.

Mechanical Design:

  • Size and Mounting: The 3RW4037-1BB14 belongs to the S2 size category, with dimensions of 55mm (width), 160mm (height), and 170mm (depth). It can be mounted using screw and snap-on methods.
  • Mounting Position: The device is versatile, allowing additional fan installation for rotation and tilt options. Without an additional fan, it remains rotatable and tiltable within specified limits.
  • Installation Altitude: Suitable for installation at altitudes up to 5,000 meters above sea level.

Electrical Connections:

  • Connection Type: Screw-type terminals are employed for both the main current circuit and the auxiliary/control current circuit.
  • Auxiliary Contacts: The device features 2 normally open (NO) and 1 change-over switch for auxiliary contacts.
  • Conductor Cross-Section: Supports a variety of conductor cross-sections for different applications and terminal points.

Ambient Conditions:

  • Temperature Range: The soft starter is operational in temperatures ranging from -25°C to +60°C, ensuring adaptability to diverse environments.
  • Protection Class: The 3RW4037-1BB14 has an IP00 protection class, indicating an open design without specific ingress protection.

Frequently Asked Questions 

1. What is the Siemens 3RW4037-1BB14 Sirius Soft Starter used for?

  • The 3RW4037-1BB14 is a soft starter designed for efficient and controlled acceleration of three-phase motors in standard applications. It ensures smooth motor startup, reducing mechanical stress and preventing sudden voltage spikes.

2. What does "Soft Starter" mean?

  • A soft starter is an electronic device that gradually increases the voltage applied to a motor, providing smooth acceleration. This helps in reducing the inrush current and mechanical stress during startup.

3. Does the soft starter include motor overload protection?

  • Yes, the 3RW4037-1BB14 features motor overload protection. It monitors and responds to overload conditions, preventing damage to the motor.

4. Can the current limitation be adjusted on this soft starter?

  • Yes, the soft starter allows for adjustable current limitations, providing flexibility and customization based on the specific requirements of the application.

5. Does it support an inside-delta circuit?

  • No, the 3RW4037-1BB14 does not include an inside-delta circuit. This feature is not available in this particular soft starter model.

6. What is the operating voltage range for this soft starter?

  • The soft starter supports an operating voltage range of 200-480V with standard circuitry.

7. What type of mounting options does it offer?

  • The soft starter can be mounted using screw and snap-on methods. It also allows additional fan installation for rotation and tilt options within specified limits.

8. Can the Siemens 3RW4037-1BB14 Soft Starter be used at high altitudes?

  • Yes, the soft starter is suitable for installation at altitudes up to 5,000 meters above sea level.

9. What is the IP rating of the 3RW4037-1BB14?

- The device has an IP00 protection class, indicating an open design without specific ingress protection. It is recommended for use in controlled indoor environments.

Siemens products are manufactured in Germany and are designed for Automotive, aerospace, power generation, and electronics usage. They come with a 2-year warranty from MRO Electric. We also carry Breakers from other manufacturers such as FANUC and Yaskawa.

Contact Us Today For More Information About Siemens Products

Check out the rest of our Siemens product line. Whether it's using our online instant quote feature, giving us a call at (800) 691-8511, or emailing us at, we strive for customer satisfaction first. This means lower prices and better service for you. For more products like 3RW4037-1BB14, take a look at more from our Breakers line. If your current unit has gone bad, take advantage of our Core Exchange program for the most inexpensive route. You can learn more about this program on our FAQ page here. We offer a repair service on all of our 3RW4037-1BB14 products that keep your downtime to a minimum. To stay up to date on manufacturer news, as well as access any of our datasheets, manuals, or other documentation, we suggest you take a look at our blog.

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