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Motor and VFD Calculator

Synchronous speed, slip, full-load current and V/Hz for 50 Hz and 60 Hz motors.

Free. No sign-up. Runs entirely in your browser, so nothing you type is uploaded or stored.

Synchronous speed

1,500 rpm

Slip

2.67 %

Full-load current (approx.)

14.2 A

Rated torque

49.1 N·m

V/Hz ratio

8 V/Hz

At 40 Hz: about 1,168 rpm, and a constant-V/Hz drive applies about 320 V. Above base frequency the voltage stays at rated and torque falls.

Estimates from the standard formulas. The nameplate full-load current is the figure to use for protection and cable sizing, which must follow your local electrical code.

How to use it

  1. 1Pick your grid frequency: 50 Hz in most of the world, 60 Hz in the Americas and parts of Asia.
  2. 2Copy power, voltage, speed, power factor and efficiency from the nameplate.
  3. 3Check the calculated current against the nameplate; use the nameplate for protection.
  4. 4Try a drive frequency to see the speed and voltage it gives.