What Is The Function Of An HVAC Variable Frequency Drive?

Before going into details about the uses and function of HVAC variable frequency drive, we better tackle first what exactly is this thing. Well, VFD or otherwise called as variable frequency drive is a type of motor controller that drives an electric motor by varying the frequency and voltage of its power supply.

Now, let us go to its main function. VFD’s function is to respond to a signal from a controller that will allow it to run at the power needed to meet the heating and cooling demands. The most common uses of VFD are for control of fans, pumps and compressors. It is normally wired in series between the main power source and the motor. It also has a bypass switch so that HVAC operation will not be interrupted if VFD needs maintenance. VFD are considered as the speed control even though it only controls the frequency and voltage of power supplied to the motor. It is because the result of this control may adjust or affect the motor speed.

Now, why is it necessary to adjust the motor speed? There are many reasons and advantages as to why it is necessary. Here are as follows:

  • Cost efficient as it saves energy

By ramping up the motor speed slowly, saving energy is possible by reducing the in-rush and mechanical issues associated with starting motors. Proper usage of VFD will result to fewer mistakes and could lead to increase in production level.

  • System efficiency

When motor has lesser mechanical stress on machines that means machine and motor life will be extended. It can be done by decreasing the fluid flow into an AC motor, which in turn decreases the pressure and friction on the valves and other machinery inside the motor. With this, wear and tear on the motor will be reduced.

  • Helps in controlling operating speed and acceleration

This allows conveyor belts to smoothly rev up rather than an abrupt jerk to full power.

  • Matching the speed to the process requirement.

The drive is capable of limiting and adjusting the mount of torque so the ac motor never surpasses the limit which actually protects the process or the product.

  • Much improve working environment since it has lower noise levels from fans and pumps which is good for manpower and people involved in the operation.