Industrial Equipment, Machinery & Capital Goods worked example

FAT Workload at 22% retest and customer witness allowance: a worked example in industrial equipment, machinery & capital goods

This worked example runs the fat workload numbers for a tougher week than the baseline: 22% retest and customer witness allowance instead of the typical 30%. Estimate factory acceptance test workload from FAT checkpoints, test throughput, and retest allowance.

The inputs for this scenario

  • FAT checkpoints and test cases: 180 checks (held at the documented default)
  • FAT completion throughput: 14 checks / hr (held at the documented default)
  • Retest and customer witness allowance: 22 % (the input this scenario stresses; the baseline uses 30)

Working through the calculation

  • The calculation starts from the formula this tool documents: Base FAT time = FAT checkpoints and test cases รท FAT completion throughput.
  • Required FAT workload works out to 15.69 hr at these inputs, and this is the headline figure for the scenario.
  • Base FAT time works out to 12.86 hr at these inputs.
  • Retest and customer witness allowance works out to 22 % at these inputs.
  • FAT completion throughput works out to 14 pieces / min at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where retest and customer witness allowance sits at 30% and the headline result is 16.71 hr, this scenario comes in 6.15% below the baseline at 15.69 hr.
  • Use it when planning the FAT window for a built-to-order machine or skid, before you commit a date to the customer's witness team. 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 FAT workload: 15.69 hr (headline result)
  • Base FAT time: 12.86 hr
  • Retest and customer witness allowance: 22 %
  • FAT completion throughput: 14 pieces / min

Run it with your numbers

  • To rerun this with your own numbers, open the live FAT Workload calculator, set retest and customer witness allowance to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.