How to Select an AC Drive


How to Select an AC Drive

In a motion system, selecting the right drive for your AC motor is just as important as picking out the right motor in the first place. While the selection of AC motors is a little more limited, drives have increased capabilities, and you will need to choose the right one based on your system’s requirements. When you are selecting a drive, there are four key things to keep in mind, input requirements, current parameters, interface needs, and, last but certainly not least; operating environment.

Power Supply Input Requirements

This is one of the simplest things to check off the list, go through and double,check to make sure the drive matches your motor’s required input voltage, frequency, horsepower, and other operating considerations. Keep these in mind when you are looking at potential drives, and pick one that matches well with your motor.

Current Parameters

In addition to input, you will need to make sure the current requirements of your motor are compatible with the drive. Keep in mind, both the base load and peak current, and consider what type of feedback the motor gives or if you need more specific requirements like a braking module.

Interface Requirements

Just like square pegs do not fit in round holes, you will need to make sure your motor and drive have compatible interfaces. Make sure that the number of digital and analog inputs, the interface ports, and the communication protocols on the drive match up with your current motor.


Finally, operating environment is one of the most overlooked, but also the most critical, considerations when choosing a drive. All drives need to be cooled when operating, and for most drives operating at sea level atmospheric pressure and regular ambient temperature is not a problem. But what happens if you need the drive to keep working at 30,000 feet? Or if the ambient temperature is 200º C? Use the manufacturer’s derating curves to find out what performance will look like in your drive’s expected operating environment, then compensate accordingly. Trust us, it is better to pay more for a heavy-duty drive now then to have the system fail and have to buy a new one later.

Contact Your Servo Drive Source

Looking for the most rugged, high performance drives in the business? Look no further, our, servo drives consistently power the fastest fighter jets, highest-temperature drilling rigs, and most power-dense motion systems in the world. Feel free to reach out to us at 1.800.823.3235 with any questions, and we hope to see you back at this blog for more tips and tricks on making your motion systems work reliability every time.