A Beginner’s Guide to Choosing the Right VFD


A Beginner’s Guide to Choosing the Right VFD

Variable frequency drives are important mechanisms that help industrial facilities control motors. These devices vary torque and frequency for optimal motor performance and better preventative maintenance. If you’re unfamiliar with this technology, upgrading your VFDs can be challenging.

To help, we’ve put together a beginner’s guide to choosing the right VFD. Avoid purchasing the wrong make and model by asking yourself the following questions.


What Kind of Work Are You Doing?

Depending on the work you’re doing, you’ll need either a constant or variable torque drive. Variable drives work well for fans, pumps, and other simple pieces of equipment. These VFDs allow you to conserve energy while running at slower speeds.


On the other hand, constant torque drives are for heavier machines. Equipment like conveyors and extruders need continuous power to handle their workload. These VFDs can accommodate different weights and energy fluctuations to push through extreme circumstances.


How Much Horsepower Do You Need?

Next, determine your horsepower requirements. Using HP to narrow down your options will make your shopping experience much faster. However, you’ll need to keep things like voltage and amps in mind to make your final selection.


Make sure your worksite, motor, and variable frequency drive voltages are equal. Facilities with 3 HP requirements or lower can use single-phase drives. However, anything higher than that will need drives with a higher phase input.


What Speed Range Do You Need?

Controlling speed is one of the most useful functions variable frequency drives offer. Running your motors at the wrong speeds wastes energy and degrades their condition. Determine your equipment’s speed capacities to find the right VFD for your operations.


Best practices say you should over speed your motor by more than 20%. Running it at speeds lower than 20% of its maximum can result in overheating. Be cautious when choosing a VFD to avoid ruining your motors.


What Are Your Control Options?

Finally, you’ll need to consider your control options to run your equipment efficiently. Different VFDs require different control methods. Do you want to run your VFD with a wall-mounted keypad or programmable logic controller?


For PLCs, you’ll likely need ethernet cables for proper communication. You might also come across digital programming units, serial communications, and analog signal followers. A reliable VFD supplier will help you determine what’s right for your needs.


This beginner’s guide to choosing the right VFD will help you build a good foundation. You should also consult with professionals from Illinois Electric Works to make the process even easier. We have high-quality VFDs for sale that can handle any application. Give us a call, and let us show you your options.