VFD energy savings calculate
How to address this depends upon your process or calculate the VFD cost savings online.
1) You can do the theoretical math with some software on the internet;
2) you could do a before and after measurements and
3) adjust the process.
This third option is only viable if your process can allow you to run the motor at base speed. If it's a flow, typically you can adjust dampers or some other throttling method to bring the process back in control. You now take your power reading and compare them to the design condition of constant torque.
You only need to run the motor for 30 seconds to get your readings at the motor base speed. You should realize that a fixed motor (no VFD) at the correct Hp and with the correct gear ratio is the most efficient solution but that's only true if nothing changes in the process.
1) You can do the theoretical math with some software on the internet;
2) you could do a before and after measurements and
3) adjust the process.
This third option is only viable if your process can allow you to run the motor at base speed. If it's a flow, typically you can adjust dampers or some other throttling method to bring the process back in control. You now take your power reading and compare them to the design condition of constant torque.
You only need to run the motor for 30 seconds to get your readings at the motor base speed. You should realize that a fixed motor (no VFD) at the correct Hp and with the correct gear ratio is the most efficient solution but that's only true if nothing changes in the process.