A VFD simply acts as a power supply to your AC pump motor. The job is to control the input frequency and voltage to control the pump. Without a VFD, the pump will run in a fixed speed and there is no variation in speed. This also means that the pump will use the maximum amount of energy. Regulating the speed of the motor with a VFD is the best option to keep it running efficiently. Variable frequency drives (VFD) in different shapes and sizes to meet specific needs. Let us walk through the steps to choose the best VFD for your motor.
1. Check the Motor’s Power Rating
Choose a VFD for three phase motor that matches or slightly exceeds the motor’s power rating. Using a VFD with lower power can harm the motor and VFD.
2. Match the Voltage
Voltage levels can vary from 230V and 460V. It is important that the VFD mush match the motor’s voltage. The VFD and motor must use the same voltage type.
3. Know the Load Type
The selection of VFD depends on the behavior of the load type. The VFD needs to have sufficient current capability to make sure that the motor can produce the required torque. Generally load can be categorized into five types. These categories include constant torque loads, variable torque loads, impact loads, constant horsepower loads, and breakaway type loads. The required speed, size of the load, and acceleration will define the required torque. Certain VFDs can be used in all categories of load types.
4. Consider the Environment
Check the location where the VFD will work. If the location is dusty or wet, use a VFD with a high IP rating. A higher rating means better protection from dust and water.
5. Look for Safety Features
You can choose a VFD with short-circuit and over-voltage protection. The safety features help keep the motor safe.
6. Choose the Right Control Type
Selecting the right control methods lets the motor run efficiently while maximizing overall performance. These control method determines how VFD controls the motor. All control methods rely on a PWM voltage to control the motor. Basic VFDs come with simple speed controls. While advanced VFDs have PID control better suited for complex tasks. Based on the application, you can choose a VFD with simple or more advanced controls.
7. Environmental Factors
Based on the temperature and humidity, choose a VFD for three phase motor with an appropriate IP rating. Since these devices can generate heat, adequate ventilation and cooling is also a factor to take into consideration. Proper cooling or ventilation help avoid overheating and extends the lifespan of VFDs.
8. Think about Your Future Needs
Considering your future needs can help you save money later. You can choose a VFD with extra capacity of you plan to upgrade in the future. Similarly, you can choose a device with programmable settings for advanced flexibility.
Conclusion:
Follow the simple tips to choose the right VFD for three phase motor that fits your needs. Choosing the right VFD can help make your motor more efficient and reliable.