Siemens 3RW4047-1BB14

Siemens 3RW4047-1BB14 Soft Starter Overview

The Siemens 3RW4047-1BB14 is a SIRIUS S3 soft starter engineered to deliver smooth motor acceleration and deceleration while protecting mechanical components and upstream electrical infrastructure. Rated 106 A with a motor power of 55 kW at 400 V, this compact unit reduces inrush current and torque shock at startup, extending equipment life for pumps, fans, compressors, and conveyors. With broad line compatibility from AC 200–480 V and a control supply of AC/DC 110–230 V, it integrates easily into global panels and OEM designs.

Performance, Protection, and Efficiency

Soft starting minimizes voltage dips, belt slippage, water hammer, and gear stress, improving uptime and lowering maintenance costs. The 3RW4047-1BB14 includes integral electronic motor protection, adjustable ramp-up/ramp-down times, and current limiting to tailor starts to your load. These features help stabilize processes, reduce energy spikes, and protect downstream gear, all within a robust SIRIUS platform trusted in continuous-duty applications.

Flexible Installation and Control

Designed with screw terminals for quick, secure wiring, this S3 frame soft starter streamlines commissioning and service. Clear front-panel access and parameter dials simplify configuration, while status indication aids diagnostics. It's 40 °C rated operating environment supports typical cabinet conditions, with derating curves available for higher ambient temperatures. The versatile control supply (AC/DC 110–230 V) allows seamless interface with standard PLC I/O and control transformers.

Broad Application Range

From HVAC to water/wastewater and general manufacturing, the 3RW4047-1BB14 delivers consistent, repeatable starts that protect both the motor and the driven load. It's a strong alternative to full-voltage starters where electrical or mechanical shock is a concern, and a cost-effective option versus VFDs when fixed-speed operation is acceptable but gentler starting is required.

Immediate Availability with Warranty

This Siemens soft starter is available immediately with free shipping and backed by a 2-year warranty from MRO Electric. Rapid fulfillment and expert support help you cut downtime and keep production on schedule.

Frequently Asked Questions

What motor size does the 3RW4047-1BB14 support?

It's rated for 55 kW at 400 V and 106 A, suitable for many mid-size three-phase motors.

What line voltage range is supported?

It works on AC 200–480 V three-phase mains.

What control voltage does it require?

The control supply accepts AC/DC 110–230 V for flexible panel integration.

Does it provide a soft stop as well as a soft start?

Yes, adjustable ramp-down helps reduce water hammer and mechanical shock on stop.

Is electronic motor protection included?

Yes, it features integrated protective functions and adjustable current limiting.

How is wiring handled?

It uses screw terminals for straightforward, reliable connections.

What ambient temperature is it rated for?

The standard rating is 40 °C; consult derating data for higher temperatures.

Where is this soft starter typically used?

Commonly in pumps, fans, compressors, conveyors, and general fixed-speed machinery.

Is it a replacement for a VFD?

Use it when you need gentle starts/stops but do not need variable speed during run.

Is it in stock and warrantied?

Yes, it's available immediately, ships free, and includes a 2-year warranty.

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 sales@mroelectric.com, we strive for customer satisfaction first. This means lower prices and better service for you. For more products like 3RW4047-1BB14, 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 3RW4047-1BB14 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.