Different converters range from 18-pulse (for the 3 kV Class) up to 54-pulse (for the 11 kV Class) producing very low harmonic distortion levels. The drive operates at up to 11,000 Vac output to the motor, with power levels up to 10,000 kVA. The 11 kV inverter has an 18-level output for motor friendly operation. The output variable frequency can be adjusted from 0 to 72 Hz, and controlled using a variety of standard local area networks allowing computer speed control.