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VFD Output Current Class Estimate

Applies a user-selected design factor to motor nameplate current to calculate a generic current target. Final drive selection must follow manufacturer sizing and overload data.

Inputs

Range: 0.001–100,000 A

Enter the motor nameplate FLA used for the drive manufacturer sizing check.

Range: 1–1,000 %

Enter the documented engineering factor for the intended duty. Verify overload, ambient, carrier-frequency, and manufacturer rules separately.

Range: 0.001–100,000 A

Enter the candidate drive output-current rating for the same duty and overload class.

Result

Candidate rating minus target
3.00 A
Preliminary drive current target
12.00 A
Preliminary drive current target
\frac{\mathrm{Motor\ nameplate\ FLA\ (A)} \cdot \mathrm{User\-selected\ design\ factor\ (\%)}}{100}
\frac{12 \cdot 100}{100}
Candidate rating minus target
\mathrm{Candidate\ VFD\ output\ rating\ (A)} - \mathrm{Preliminary\ drive\ current\ target}
15 - 12

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Screening tool. Verify the adopted NFPA 70 edition, AHJ requirements, nameplate data, and project conditions before use.