ControlMaster® Inverter Controls

ControlMaster® Inverter Controls
ControlMaster inverter controls offer more versatility, better performance and prolonged motor and brake life than industry-standard contactor controls.

About ControlMaster® Inverter Controls

Inverter controls, sometimes called variable frequency drives (VFD), are an electrical device which controls the speed of the motor. ControlMaster inverter controls can be use for the hoisting, trolley or bridge motion; however, the size of the inverter and the type of software it uses varies by its function. R&M QX® and QL cranes come standard with inverter controls for trolley and bridge motions. Inverter hoisting controls are an option for our Spacemaster® SX hoist and are a standard for the SXL wire rope hoist.

ControlMaster inverter controls provide better performance and prolong the equipment life. Dynamic braking (a technique of electric braking in which the speed reduction is controlled by the inverter) means the inverter controls the motor speed to nearly zero before the brake is engaged, significantly reducing brake wear. Controlled acceleration and deceleration provides smooth starts and stops and lowers starting currents, reducing gear and motor wear and structural stress on mechanical components and reducing load swing- leading to longer equipment life and better safety.

R&M continues to integrate cutting-edge inverter technology into our equipment. Learn more about our newest member of the ControlMaster inverter - the innovative ControlMaster Edge.

Inverter Control Versus Two-Speed Contactor Control

Inverter controls give the operator the ability to smoothly accelerate, decelerate and hold any speed between the defined minimum and maximum speed.

ep for 2 step pushbutton

Two-speed contactor controls do not offer the operator the ability to smoothly accelerate or decelerate between the defined speeds. The brake is used for slowing the speed of the equipment.

Two speed contractor control

How can your project benefit from ControlMaster inverter controls? Contact us today.

Use our Crane Designer tool to choose the cutting-edge technology that will help you rise above your competition.

 

Downloads

Spacemaster SX Brochure

R&M Product Line Card Brochure

Special Features Brochure

Gallery

ControlMaster Inverter Controls FAQs

What Are ControlMaster Inverter Controls and How Do They Differ from Standard Contactor Controls?

R&M ControlMaster inverter controls are variable frequency drive (VFD) devices that control motor speed and torque for hoist, trolley and bridge motions in an overhead crane system. Unlike simple two‑speed contactor controls, the ControlMaster inverter provides smooth, stepless acceleration and deceleration between defined minimum and maximum speeds.

Compared with standard contactor‑type crane controls, inverter controls use advanced technology to reduce brake wear, mechanical fatigue and load swing. This approach helps improve handling precision and extends the life of the entire crane drive system.

Show

Which Motions Can the ControlMaster System Control?

R&M ControlMaster inverter controls can manage hoist, trolley and bridge motions. These controls provide smooth starts and stops, reduce load swing and extend motor and brake life.

On R&M cranes, trolley and bridge inverter technology is standard as part of a complete crane package. Hoisting inverter controls are optional on rope hoists, enabling an expanded range of operator assist features and precision load handling controls.

Show

What Are the Benefits of Using Inverter Controls for Brake and Motor Longevity?

With inverter control, dynamic braking is handled primarily by the VFD rather than the mechanical brake. The VFD slows the motor to near zero speed before the brake sets, instead of using the brake to decelerate a moving load. This inverter-controlled braking approach significantly reduces brake wear. It also lowers mechanical stress on the motor, extending its service life.

Show

Are ControlMaster Inverter Controls Compatible with all R&M Hoists and Crane Systems?

R&M ControlMaster inverter controls are designed specifically for hoist and crane applications and integrate seamlessly with R&M’s modern hoist and crane portfolio, including Spacemaster® SX and SXR rope hoists as well as the QX® wire rope hoist crane and QL electric chain hoist crane packages.

Show

What Maintenance or Monitoring Features Are Available for These Inverters?

ControlMaster inverters are designed to be part of a modern overhead crane control system, with parameter settings and diagnostics accessible through the inverter keypad or app, depending on the model. Typical parameters include status and fault codes that support troubleshooting in your industrial motor control system.

When used with R&M’s digital tools as a part of a complete fieldbus crane, these controls help maintenance teams track operating hours, starts and event histories—improving visibility into whole crane performance.

Show

What Should Be Considered When Choosing Inverter-Controlled Systems for New Crane Applications?

When specifying VFD crane control system solutions for new projects, key factors include:

  • Application and duty – required speeds, cycles and precision for hoist, trolley and bridge motions
  • Load characteristics – capacity, type of material being handled and need for fine positioning
  • Operator assist features – level of crane automation and motion control, from basic variable speed crane controls to advanced anti‑sway or synchronized motions
  • Infrastructure – available power, harmonics considerations and enclosure/environmental requirements for the inverter control panel for the crane
  • Lifecycle cost – benefits of longer brake and motor life, reduced maintenance and improved safety compared with inverter vs contactor controls alone

R&M’s Crane Designer tool can help you configure a complete overhead crane control system, including VFDs for hoist or crane motions and advanced crane control technology such as ControlMaster inverter controls, tailored to your facility and production goals.

Show