Key Benefits of Allen-Bradley Drives: Efficiency, Durability, and Cost Savings

Rockwell Automation, an American manufacturer of industrial automation technologies, provides a comprehensive selection of Allen-Bradley motor drives.  Motor drives are basically electronic devices that control the speed, direction, torque, and power output of electric motors.

They are mainly classified into the following categories:

• DC Motor Drives: A DC drive is a power module or amplifier that interfaces between a DC motor and logic controller.  It takes in direction and step input from the controller and then converts it into an appropriate current and voltage output for the connected motor.

DC drives are primarily used to provide reliable braking, speed regulation, reversing, and frequent starting solutions for brushless & brushed DC motors, DC servo motors, linear motors, and voice coil motors. Typical applications include paper production machines, mine winders, cranes and hoists, textile mills, machine tools, excavators, crushers, rolling mills, elevators, and spindle drives.

• AC Motor Drives: Also known as Variable Frequency Drives (VFDs) or inverters, AC drives are a type of frequency converters designed to regulate the torque and speed of electric motors – most often three-phase AC induction motors or sometimes single-phase induction motors, brushless DC (BLDC) motors, permanent magnet synchronous motors (PMSMs), or synchronous motors.

They convert incoming fixed-frequency, constant-voltage AC input into a variable-frequency, adjustable-voltage AC output that is conveyed to the connected motor. Thus, the speed and torque of the motor can be controlled by appropriately varying the motor’s input AC frequency and associated supply voltage.

AC drives are extensively used in industrial plants to precisely control motors powering compressors, fans, pumps, conveyor belts, and other types of industrial machinery & equipment.

• Servo Motor Drives: A servo drive is an electronic device that forms an essential part of a closed-loop servo system, which also includes a DC or AC servo motor, feedback device, and servo controller. The drive receives a position, velocity, or current command signal from the controller and compares it with a feedback signal provided by the feedback device. It then adjusts or amplifies the received signal accordingly to deliver the desired amount of voltage and current to the connected AC or DC servo motor so as to realize the required motion profile.

In servo drive systems, instead of the connected DC or AC servo motor is controlled by a variable input signal, it’s controlled by the feedback signal, which is generated by comparing the system’s reference or input signal and output signal. Servo drives are ideally suited for material handling, robotics, packaging, converting print, manufacturing assembly lines, and web handling applications.

• Stepper Motor Drives: These are electronic power converters that convert pulse signals from a logic controller into motor motion to attain accurate positioning. They enable precise positioning of stepper or brushed DC motors with ease and can operate using a DC or AC input. In a stepper drive system, the speed of the connected motor is controlled by varying the frequency of the pulses.

Stepper motor drives find applications in robotics, 3D printing, manufacturing, precise positioning of telescopes and antennas, and industrial automation.

Available Allen-Bradley Drives

PowerFlex Variable Frequency Drives

The Allen-Bradley PowerFlex family of AC drives provides versatile, easy-to-use medium-voltage and low-voltage VFD solutions for demanding industrial applications with diverse power requirements. With innovative features and an extensive range of power ratings, these drives deliver application flexibility and high-performance motor control while simplifying system setup, programming, and operation.

PowerFlex DC Drives

Allen-Bradley PowerFlex DC digital drives provide high-performance control and drive solutions and can be easily configured for a wide array of DC motor applications and retrofits. They are available in power ratings ranging from 1.5 to 1400 Hp/1.2 to 1044 kW at 200 to 690V AC input in both non-regenerative and regenerative drive configurations.

Kinetix Servo Drives

Allen-Bradley Kinetix drives are productivity-enhancing servo drives that leverage the capabilities of the Allen-Bradley Logix control platform to provide a highly flexible and scalable servo control solution for a broad range of industrial applications.

As an integral part of the Kinetix Integrated Motion control solution, these drives fit seamlessly into the Allen-Bradley Integrated Control Architecture, providing simplified machine design, configuration, commissioning, and operation, as well as enhanced system performance.

Key Benefits of Allen-Bradley Drives

Improved Efficiency

The following features enable Allen-Bradley motor drives to deliver improved system/machine efficiency:

• Multiple Hardware and Control Options: Allen-Bradley PowerFlex drives and Kinetix servo drives are available, and they have a comprehensive selection of cutting-edge hardware and control technologies that enhance machine efficiency and productivity across multiple industries.
• Predictive Diagnostics: Most Allen-Bradley motor drives incorporate innovative predictive diagnostic features that help reduce unscheduled downtime, consequently improving system efficiency and reliability. Also, with advanced notification capabilities, these drives provide users with alerts of irregular drive operating parameters, enabling them to schedule maintenance downtimes with minimal production interruptions.
• Embedded Safety Options: Safety options, such as Category 3, PLe, SIL3 Safe Torque Off and Category 4, PLe, SIL 3 Safe Speed Monitor, can be easily integrated into most Allen-Bradley motor drives to enhance personnel safety, capture valuable machine performance information and diagnostics, simplify drive installation and commissioning, and improve machine/system availability through reduced downtime.
• System-wide Connectivity: Allen-Bradley motor drives support a wide variety of communication protocols and industrial networks, enabling system-wide communications that help improve machine/system efficiency and productivity.

Essentially, system-wide connectivity provides a seamless flow of real-time information and increased visibility to machine-level and system data. This leads to better remote monitoring, more informed decision-making, improved system-wide optimization, and faster troubleshooting with readily available diagnostic information.

• Integrated Motion: Allen-Bradley drives can provide improved system efficiency with Integrated Motion on SERCOS interface or EtherNet/IP network. This type of motion integration provides high-performance open- and closed-loop drive control on a single, flexible communication network, improving system efficiency and eliminating the need for dedicated motion control modules and networks.

It also allows users to expand their motion control solutions to include motor drives with a higher power range and a wider selection for motor and feedback support.

• Automatic Device Configuration (ADC): This feature lets connected Allen-Bradley Logix controllers detect replaced Kinetix servo drives and PowerFlex AC/DC drives and download all the appropriate configuration parameters automatically over an EtherNet/IP network, reducing the need for manual system reconfiguration. This helps to enhance system efficiency and productivity by facilitating plug-and-run functionality and keeping the system running smoothly.
• Auto-Tuning and Adaptive Control: Various Allen-Bradley motor drives include an adaptive Autotune feature that enables them to continuously monitor the operational characteristics of connected motors and optimize drive output. They also incorporate adaptive control capabilities that allow them to automatically adapt to the individual operating conditions of connected motors to maintain optimal production. This ensures dynamic efficiency and improved performance.

• Reactive Power Compensation: Allen-Bradley motor drives, particularly the PowerFlex AC drives, can help improve the power factor of your motion control system by compensating the reactive power drawn by the connected motors. This reduces stress on the line side of the AC drives and improves the overall system efficiency. The reactive power compensation is provided by the capacitors that are included in the DC link of the PowerFlex VFDs.

Durability

Using Allen-Bradley Kinetix servo drives and PowerFlex AC/DC drives can significantly extend the service life of your motors and other components included in your motion control system. These drives are conformal coated (with XT corrosive fluid protection) or packaged in enclosures with higher IP ratings and can, therefore, prevent corrosive agents, dust, moisture, and other contaminants from affecting the motors and other system components, consequently prolonging their lifespan.

With advanced self-monitoring capabilities, Allen-Bradley motor drives can notify users of technical issues, such as faulty cables, blown fuses, loose connections, and exhausted runtime hours of critical components, that can compromise the health and lifespan of the drive system components (e.g., motors, controllers, I/O modules, communication cards, etc.).

In addition, predictive diagnostics, such as time-stamped events, allow Allen-Bradley Kinetixand PowerFlex motor drives to keep track of real-time information regarding the health status of their internal components, relay outputs, cooling fans, and connected external devices (like motors and controllers), providing users with advanced alerts of required maintenance. This helps the users to identify and resolve issues much more quickly, thereby increasing the service life of the drive system components and preventing major failures.

Allen-Bradley drives can also minimize the wear and tear of your motion control system components by providing smooth and accurate control of motor speed and torque. For example, by continually adjusting the voltage and frequency being supplied to connected motors, PowerFlex AC drives allow ultra-precise control of motor speed and torque output. This enables users to fine-tune motor-powered industrial processes for maximum efficiency.

Cost Savings

Allen-Bradley motor drives offer cost savings in the following ways:

• Energy Cost Savings: One of the greatest benefits of using Allen-Bradley drives in motion control systems is substantial energy savings, as energy consumption is a major operating cost in industrial plants. Significant energy savings can be achieved by adjusting the speed of AC or DC motors to exactly match the load requirements of a given application, rather than the motors running at constant full speed.

A variety of Allen-Bradley Kinetix and PowerFlex motor drives include innovative technologies that enhance energy efficiency. These include:

• Active Front-End (AFE) Technology: This technology transfers regenerative energy onto the incoming voltage supply. Allen-Bradley drives with regeneration capability help minimize energy consumption by transferring regenerative energy from connected motors back to the incoming voltage supply, leading to substantial energy cost savings.
• Permanent Magnet Motor Control Option: Many Allen-Bradley drives have a control option for permanent magnet motors. These motors provide a higher power density, often resulting in motor size reduction while still maintaining the same amount of torque output. Therefore, using permanent magnet AC or DC motors in an Allen-Bradley drive system can help boost energy efficiency and cut down related costs.
• Adaptive Control: This technology helps users obtain optimal drive tuning to maximize motor torque and output current, consequently reducing energy consumption.
• Economizer Mode: Some Allen-Bradley motor drives provide an Economizer mode, which comprises Sensorless Vector Control capability and additional energy-saving functions. Sensorless vector control offers exceptional motor speed regulation, resulting in reduced energy consumption.
• Synchronous Transfer System: This system matches the power output of a motor drive to the utility’s power supply with seamless sync-down and sync-up transitions. In doing so, it helps lessen peak energy charges.
• Downtime Costs Reduction: Most Allen-Bradley motor drives have predictive diagnostics that are designed to monitor the drives’ internal components as well as connected devices and provide real-time operational data for predictive maintenance. With higher-level predictive analytical models, maintenance teams can analyze the provided data and effectively schedule maintenance downtimes without major production disruptions. This helps reduce unplanned downtime costs.
• Safety-related Costs Reduction: Allen-Bradley Kinetix servo drives and PowerFlex AC/DC drives are available with integrated safety functions, built-in protection features, and hardwired or networked safety options, such as Category 3, PLe, SIL3 Safe Torque Off option and Category 4, PLe, SIL 3 Safe Speed Monitor option, which provide advanced machine and operator safety. This helps reduce/eliminate costs related to workplace accidents or machine breakdowns stemming from improper operation or electrical faults.