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2-year Warranty

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Siemens 3RW4056-6BB34

SIRIUS SOFT STARTER, S6, 145 A, 100 HP/460 V, 50 DEG., 200-460 V AC, 115 V AC
1 rating

1 Available

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2 Year warranty

Part Number3RW4056-6BB34
Model #3RW40566BB34
Warranty2 Year
DescriptionSoft starter
FeaturesIntegrated bypass contact system , Thyristors
Pollution3, acc. to IEC 60947-4-2
Frequency50/60 Hz
Voltage 115 V
MountingVertical mounting surface +/-90° rotatable
Connections/ TerminalsBusbar connection, for auxiliary and control circuit screw-type terminals
Ambient temp-25 ... +60

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 3RW4056-6BB34 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 3RW4056-6BB34 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 3RW4056-6BB34, 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 3RW4056-6BB34 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 3RW4056-6BB34 Overview

Siemens SIRIUS Soft Starter 3RW4056-6BB34

The Siemens SIRIUS Soft Starter 3RW4056-6BB34 is a robust and versatile solution designed for industrial motor control applications. With a focus on efficiency and reliability, this soft starter offers advanced features to ensure smooth and controlled motor operation.

Integrated Bypass Contact System: 

Featuring an integrated bypass contact system, the SIRIUS 3RW4056-6BB34 simplifies installation and minimizes energy consumption by reducing heat dissipation during operation. This innovative design enhances system efficiency while maintaining optimal performance.

Advanced Protection Features: 

Equipped with intrinsic device protection and motor overload protection, the 3RW4056-6BB34 prioritizes safety and reliability in motor control applications. With external reset capability and adjustable current limitations, it offers flexible protection tailored to specific operational requirements.

Enhanced Functionality: 

The SIRIUS 3RW4056-6BB34 soft starter offers a range of functional capabilities, including motor overload protection and adjustable current limitation. While it does not include evaluation for thermistor motor protection or an inside-delta circuit, its comprehensive feature set ensures precise control and optimal performance.

Compact and Durable Design: 

Built to withstand harsh industrial environments, the 3RW4056-6BB34 soft starter boasts a durable construction and compact design. With a size classification of S6 and dimensions of 120mm x 198mm x 250mm, it offers versatile mounting options for seamless integration into existing systems.

Efficient Power Electronics: 

The S6 145 A soft starter delivers efficient power management for 3-phase motors, offering rated performance values at various operating temperatures and voltages. By minimizing power loss during operation, it maximizes energy efficiency and reduces operational costs.

Flexible Control Options: 

Featuring AC control supply voltage with frequency options of 50Hz and 60Hz, the S6 145 A soft starter provides flexible control capabilities tailored to specific application requirements. Its red fault signal display ensures quick and easy identification of system issues.

Comprehensive Terminal Connections: 

The SIRIUS S6 145 A soft starter offers versatile terminal connections, with options for busbar connection for main current circuits and screw-type terminals for auxiliary and control circuits. It also supports a wide range of connectable conductor cross-sections, providing flexibility in wiring configurations.

Reliable Performance in Challenging Environments: 

Designed to operate in demanding conditions, the 3RW4056-6BB34 soft starter is rated for installation altitudes up to 5,000 meters and ambient temperatures ranging from -25°C to +60°C. With protection against environmental factors and UL/CSA ratings for added assurance, it ensures reliable performance in diverse industrial settings.

FAQs for Siemens SIRIUS Soft Starter 3RW4056-6BB34

Q: What is the Siemens SIRIUS Soft Starter 3RW4056-6BB34 used for? A: The SIRIUS Soft Starter S6 145 A is designed for industrial motor control applications, providing smooth and controlled starting and stopping of motors to reduce mechanical stress and energy consumption.

Q: What are the key features of the 3RW4056-6BB34 soft starter? A: Some key features include an integrated bypass contact system for energy efficiency, intrinsic device protection, motor overload protection, adjustable current limitation, and external reset capability.

Q: Does the 3RW4056-6BB34 soft starter support motor overload protection? A: Yes, the S6 145 A soft starter includes motor overload protection to safeguard motors from excessive current and prevent damage during operation.

Q: What are the dimensions and mounting options for the 3RW4056-6BB34 soft starter? 

A: The 3RW4056-6BB34 soft starter is 120mm x 198mm x 250mm and is classified as size S6. It offers flexible mounting options, including vertical mounting surfaces rotatable up to +/—90° and tiltable to the front and back up to +/—22.5°.

Q: What are the ambient temperature and altitude limits for operation? A: The 3RW4056-6BB34 soft starter is rated for ambient temperatures ranging from -25°C to +60°C and can be installed at altitudes up to 5,000 meters above sea level.

Q: What types of terminal connections does the 3RW4056-6BB34 soft starter support? A: The S6 145 A soft starter supports busbar connections for main current circuits and screw-type terminals for auxiliary and control circuits, accommodating various conductor cross-sections.

Q: Does the 3RW4056-6BB34 soft starter provide fault indication? A: Yes, the S6 145 A soft starter features a red fault signal display for quick identification of system issues, enhancing troubleshooting efficiency.

Q: What are the UL/CSA ratings for the 3RW4056-6BB34 soft starter? A: The S6 145 A soft starter has UL/CSA ratings of B300/R300 for contact rating of auxiliary contacts, ensuring compliance with safety standards in North America.

Q: Can the 3RW4056-6BB34 soft starter be used with different control supply voltages and frequencies? A: Yes, it supports control supply voltages of 115V AC at frequencies of 50Hz and 60Hz, providing flexibility for various application requirements.

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 3RW4056-6BB34, 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 3RW4056-6BB34 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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