Function Application
‑569‑
Figure 3‑38 User‑defined multi‑point V/f curve
Parameters F3‑03 to F3‑08 are used to define a multi‑point V/f curve. In this case,
frequency points range from 0.00 Hz to the rated motor frequency. The voltage points
range from 0.0% to 100%, corresponding to the voltage range from 0 V to the rated
motor voltage. Generally, the multi‑point V/f curve is set based on load characteristics
of the motor. Ensure the following conditions are met: F3‑03 ≤ F3‑05 ≤ F3‑07. To
ensure correct setting, the AC drive restricts the relationship of F3‑03, F3‑05, and F3‑
07. Set F3‑07 first, then F3‑05, and finally F3‑03.
Square V/f curve
The following figure shows a variable torque square V/f curve.
Figure 3‑39 Variable torque square V/f curve
Below the rated frequency, the relationship between the output voltage and the
output frequency of the AC drive changes according to the 2‑power curve. This curve
is applicable to scenarios with light loads that seldom change, such as fans and water
pumps.
To Next Page
Loading...
