Receive a Text Quote
We will send you price and availability shortly
Invalid number. Please call (800) 691-8511
Looking for a fast quote? Click here, and we'll text you.

2-year Warranty

Same Day Shipping

Siemens 3RW4074-6BB34

SIRIUS SOFT STARTER S12, 248 A, 200 HP/460 V, 50 DEG., 200-460 V AC, 115 V AC, SCREW TERMINALS
1 rating

Select Condition


1 in stock


Request a formal quote

  • Ships Today
  • 2 Year Warranty
Part Number3RW4074-6BB34
Model #3RW40746BB34
Warranty2 Year
CategorySoft start S12
FunctionMotor overload protection
Insulation voltage rating 600 V
Operating currentat 40 °C rated value A 280, at 50 °C rated value A 248, at 60 °C rated value A 215
Voltage200-460 V
Operating frequency50/60 Hz
Control Size S12
MountingScrew fixing
Degree of pollution3, acc. to IEC 60947-4-2
DesignationSoft starter
Height230 mm
Width 160 mm
Depth278 mm
Main current circuit connectionBusbar connection
Auxiliary and control current circuitScrew-type terminals
Installation altitude5000 m
Ambient temp-25-+60 °C
UL/CSA ratings100 hp at 220/230 V, 200 hp at 460/480 V

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 3RW4074-6BB34 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 3RW4074-6BB34 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 3RW4074-6BB34, 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.

  • Shipping Weight : 25lbs

Want it shipped tomorrow?

  • Order within the next 17 hours and 13 minutes.
  • If you order between 4pm and 6pm EST, you will be charged a small rush fee.

Ask about exchanging your faulty 3RW4074-6BB34 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 3RW4074-6BB34 Overview

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.

SIRIUS 3RW40746BB34 

The 3RW40746BB34 is a powerful and versatile soft starter designed as part of the SIRIUS product line by Siemens. This soft starter is equipped with various advanced features and functions that make it an essential component in motor control applications. Its integrated bypass contact system, along with thyristors, enhances its efficiency and reliability.


One of the standout features of the 3RW40746BB34 is its intrinsic device protection. This ensures that the soft starter itself remains safeguarded against potential faults or malfunctions, thereby contributing to the overall durability of the system. Additionally, motor overload protection is a critical function that prevents excessive current from damaging the motor during startup, ensuring a longer lifespan for both the motor and the soft starter.


The soft starter's external reset capability adds to its user-friendliness, allowing for easy reconfiguration and adjustments. The adjustable current limitation feature further enhances its versatility, making it compatible with a wide range of motor types and sizes. However, it's worth noting that this model does not offer the evaluation of thermistor motor protection, which may be a consideration in specific applications.


The 3RW40746BB34 demonstrates its flexibility with its compatibility across various operating frequencies, rated voltages, and load conditions. Its wide operating voltage range (200V to 460V) and adjustable motor current for motor overload protection (minimum rated value of 130A) cater to diverse motor setups. The minimum load requirement of 20% ensures that the soft starter remains effective even during partial load conditions.


In terms of power electronics, the soft starter exhibits remarkable performance. It can handle substantial mechanical power outputs for three-phase motors, reaching up to 160,000 W at 400V and 40°C. This capability makes it suitable for driving high-power motors commonly found in industrial applications.


The control circuit and supply voltage specifications of the 3RW40746BB34 contribute to its reliability and ease of use. The control supply voltage of 115V at both 50Hz and 60Hz ensures consistent performance. The fault signal display version features a red indicator, enhancing the device's ability to communicate its status to operators.


From a mechanical standpoint, the soft starter is designed for convenience and efficiency. Its compact size (S12) and adaptable mounting options allow for seamless integration into various setups. The required spacing for side-by-side mounting ensures proper ventilation and heat dissipation.


The 3RW40746BB34 also boasts a comprehensive set of connection options, accommodating various conductor cross-sections and types. Its compatibility with different conductor sizes and specifications makes it suitable for a wide range of electrical configurations.

Environmental Consideration

Regarding environmental conditions, the soft starter can operate in a broad temperature range (-25°C to +60°C) and handle altitudes up to 5,000 meters. Its IP00 protection class indicates that it is not inherently protected against solids or liquids but is designed for installation within enclosures.

In conclusion, the 3RW40746BB34 soft starter from Siemens' SIRIUS product line is a highly capable and adaptable motor control device. With its integrated bypass contact system, thyristors, intrinsic device protection, motor overload protection, and adjustable current limitation, it addresses the needs of various industrial applications. Its impressive mechanical power output, control circuit features, and robust construction make it a reliable and efficient choice for motor control and protection.

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 3RW4074-6BB34, 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 3RW4074-6BB34 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.

5 stars

4.9 Overall Satisfaction Rating

Over 1700 Ratings from Actual Customers

Read Our Reviews

Very happy with the overall service, delivery, communication and delivery,

Conley Cooke

I needed a special drive, found it, and I was quickly assisted by Joe Kaminski. Everything was exactly as it should be....


We have an older DMU80 CNC Machine and the Handheld Control was damaged beyond repair. MRO was very helpful in confirmin...

Abbey-Purchasing Specialist