Industrial Engineer · phase 9 of 16
Motor Base Frequency
Nameplate frequency at which the motor reaches rated voltage and normally transitions from constant-torque to field-weakening operation.
The Explain card
- Plain English
- Base frequency is the frequency at which the motor reaches its nameplate voltage. Below it the drive raises voltage with frequency, and above it the voltage can go no higher.
- Example
- A 60 hertz motor on a 60 hertz base gets full voltage at 60 hertz. Set the base to 50 hertz and it gets full voltage at 50, and runs over fluxed and hot at 60.
- Why it matters
- Base frequency is where the motor stops being in the constant torque region and starts losing torque with speed. A wrong entry either cooks the motor or starves it, and neither one shows up as a drive fault.
- Hook
- The corner of the volts per hertz line.
Where it sits in the deck
Phase 9: VFD Ratings, Sizing, and Motor Data
Nameplate arithmetic, where the currents, voltages and duty ratings decide whether a drive can actually run the motor you bolted it to.
