Motors, Generators & Electrification Equipment worked example

Rotor Balancing Time at 7.2% setup, trial-weight, and recheck-spin allowance: a worked example

This worked example runs the rotor balancing time numbers for a tougher week than the baseline: 7.2% setup, trial-weight, and recheck-spin allowance instead of the typical 10%. Estimate the labor time to dynamically balance motor and generator rotors so balancing teams can plan hours, schedule the work, and confirm the job fits the shift.

The inputs for this scenario

  • Rotors to balance this run: 120 rotors (held at the documented default)
  • Balancing throughput per balancing machine: 12 rotors / min (held at the documented default)
  • Setup, trial-weight, and recheck-spin allowance: 7.2 % (the input this scenario stresses; the baseline uses 10)

Working through the calculation

  • The calculation starts from the formula this tool documents: Base rotor balancing time = rotors to balance รท balancing rate per machine.
  • Required rotor balancing time works out to 10.72 hr at these inputs, and this is the headline figure for the scenario.
  • Base rotor balancing time works out to 10 hr at these inputs.
  • Setup and recheck allowance applied works out to 7.2 % at these inputs.
  • Balancing rate per machine works out to 12 pieces / min at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where setup, trial-weight, and recheck-spin allowance sits at 10% and the headline result is 11 hr, this scenario comes in 2.55% below the baseline at 10.72 hr.
  • Use it when scheduling the balancing cell, quoting a job, or checking that balanced rotors will be ready before the motor assembly line needs them. A result at this level usually justifies acting on the stressed input before touching anything else, because every other figure in the table is downstream of it.

Results at a glance

  • Required rotor balancing time: 10.72 hr (headline result)
  • Base rotor balancing time: 10 hr
  • Setup and recheck allowance applied: 7.2 %
  • Balancing rate per machine: 12 pieces / min

Run it with your numbers

  • To rerun this with your own numbers, open the live Rotor Balancing Time calculator, set setup, trial-weight, and recheck-spin allowance to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.