Skip to main content
blog | How to Select a Servo Drive |
|
2 minute read

A servo drive should be selected based on the specific servo motor used in the application. The motion requirements of the driven mechanism determines the voltage and current requirements of the servo motor – the key information required when selecting a servo drive. The motor specification sheet indicates the peak and continuous current requirements along with the motor voltage rating. Since many servo motors have as much as a 4 to 1 peak to continuous rating, careful consideration of the application peak torque requirements is important.

After the motor voltage and current requirements is determined, a drive can then be selected since a servo drive is rated based on its voltage and current capabilities. For a brushless DC servo drive, the input voltage determines the operating DC bus voltage to power the motor. The drive specification will consist of an input voltage and continuous and peak current ratings. It should be noted that most servo drives on the market today have a 2- or 3-times peak to continuous current rating, with the peak current available for short bursts of less than a few seconds.

Example 1
Application requirements led to a selection of a motor with a voltage rating of 240 Vac, a continuous current requirement of 3 amps and a peak current of 5 amps for acceleration. The proper drive for this application would be one with a voltage rating of 240 Vac with a continuous rating of 3 amps. A 3-amp drive will likely have a 6 or 9 amp peak current rating – well within the requirements of the application.

While matching the motor voltage and current requirements will make certain the drive has sufficient operation power, several other servo drive considerations: motion requirements, feedback options, and available communication protocols, will help determine the exact servo drive suitable for the application. Whether the motor will operate in a torque, velocity or position loop will determine the complexity of the servo drive selected. Feedback options are important since a motor may incorporate a specific feedback element that must match the drive’s ability to accept. Finally, a servo drive that is incorporated into a broader automation system may need to communicate on a specific network or fieldbus.

Example 2
A motor requires 240Vac, 8 amps peak for 1.5 seconds, and a continuous rating of 2 amps. For this application, a drive with more than 8 amps would be required to meet the peak requirements. While only 2 amps are needed for continuous operation, a 3 amp continuous drive with a 9 amp peak rating would be required. With an amplifier with a rated continuous current above the motors rating, temperature monitoring would be recommended to help prevent inadvertently overheating the motor.

Selecting a servo drive requires a strong comprehension of motion control systems and the various factors that affect their performance. A motion control expert provides the expertise necessary to navigate the complexities of the selection process. In addition, a good practice is to purchase the drive and the servo motor from the same manufacturer since their ratings are optimized to work efficiently as a system.

Know your current and voltage requirements for a drive? Enter your specifications to search and compare our products, identifying what best fits your needs with our Product Selectors tool.

Consult an Expert

AKD Servo Drive

AKD® Series is a proven perfomer, supporting the largest customer installed base, and offers:

  • Industry leading motion control loops
  • Extensive motor feedback and drive fieldbus support including EtherCAT, EtherNet/IP, Profinet RT, etc.
  • Plug-and-play with Kollmorgen motors
  • WorkBench GUI, acclaimed for customer experience and usability
Learn More

AKD2G Servo Drive

Born from a rich AKD heritage, AKD2G is the latest servo drive technology adding:

  • Dual-axis technology for additional space savings
  • Built-in functional safety options via SafeMotion Monitor (including FSoE)
  • Color Graphic Display
  • Optimized for single-cable power and feedback
Learn More

Engineer the Exceptional

Learn how to engineer exceptional machines, robots and vehicles with the highest-performing, most reliable motors, drives, automation solutions and more.

Learn More

Related Resources

AKD2G Mentor Sessions: Advanced Configuration for AKD2G Dual Axis

AKD2G Mentor Sessions: Advanced Configuration for AKD2G Dual Axis >

Building from the AKD2G Quick Setup Guide, this session reviews special considerations for the dual-axis AKD2G drive. Controlling two axes in one drive provides a unique opportunity for triggering inputs, tuning, troubleshooting, and capturing data…
AKD2G Mentor Sessions: AKD2G Quick Setup Guide

AKD2G Mentor Sessions: AKD2G Quick Setup Guide >

Need to get up and running with your new 2G system? It starts with the AKD2G Workbench software. This session will give you the fundamentals you need to create motion quickly, build confidence, and accelerate your productivity.
Functional Safety 101 White Paper

Functional Safety 101: The What, Why and How >

Mandates and regulations aside, more customers are demanding functional safety. But no two applications are exactly the same, and there isn’t a one-size-fits-all solution. This whitepaper reveals how equipment manufacturers can stay up to speed.
Kollmorgen helps packaging automation solutions provider meet the need for on-demand “right-sized” packaging

Kollmorgen helps packaging automation solutions provider meet the need for on-demand “right-sized” packaging >

Kollmorgen's expertise in motion control components for packaging machinery helped Packsize tackle demanding challenges to create game-changing packaging automation solutions.

Adjusting Standard Motion Profiles to Optimize Operating Speed and Time >

Adjusting Standard Motion Profiles to Optimize Operating Speed and Time: Learn more about simple profile adjustments that can preserve motion, move time and provide memorable profiles.​​​​

Accelerating the Development of Next-Generation Prostheses and Exoskeletons >

Learn how Kollmorgen servo technology is helping OEMs accelerate the design of next-generation prostheses and exoskeletons.
Direct Drive Technology Increases the Speed and Quality of Electric Vehicle Lithium-Ion Battery Production

Direct Drive Technology Increases the Speed and Quality of Electric Vehicle Lithium-Ion Battery Production  >

One important stage in manufacturing lithium-ion batteries for electric vehicles is seal-welding the positive-terminal top cap to the battery shell. Laser welding is the ideal technology for this purpose, but it requires precise motion, speed and…
Ground satellite 

AKD2G 24A Data Sheet >

Kollmorgen’s new AKD2G 24A servo drive delivers 3x the continuous current capacity and offers a rich feature set for simple integration in complex applications. 
Kollmorgen White Paper, Monitoring and controlling brakes through on-drive functional safety technology

Monitoring and controlling brakes through on-drive functional safety technology >

How can you ensure the safety of vertical loads while complying with ISO 13849-1? On-drive safety functions offer a no-compromise way to simplify brake testing.