Municipal Waste Sorting Equipment worked example

Maintenance Downtime at 23% lock-out, clean-down, and delay allowance: a worked example

What does the result look like when lock-out, clean-down, and delay allowance reaches 23%? The full calculation is worked below with real intermediate numbers. Use it when slotting a PM window for the trommel, drum magnet, or optical sorter and you need an honest estimate before locking the shift schedule.

The inputs for this scenario

  • PM tasks in the window: 24 tasks (unchanged)
  • Technician completion rate: 0.2 tasks / min (unchanged)
  • Lock-out, clean-down, and delay allowance: 23 % (raised for this scenario; the documented default is 20)

Working through the calculation

  • Applying the documented formula (Base downtime time = PM tasks / technician completion rate) to the inputs above produces each figure below.
  • At this operating point the engine returns 148 min for required maintenance downtime, the number this scenario is built around.
  • At this operating point the engine returns 120 min for base maintenance downtime.
  • At this operating point the engine returns 23 % for lock-out and delay allowance applied.
  • At this operating point the engine returns 0.2 pieces / min for technician completion rate.

How this compares with the baseline

  • Against the tool's baseline example, where lock-out, clean-down, and delay allowance sits at 20% and the headline result is 144 min, this scenario comes in 2.5% above the baseline at 148 min.
  • A figure at this level is achievable when lock-out, clean-down, and delay allowance is genuinely sustained, not just peaked for a shift. It assumes tasks complete at a steady average rate; a single complex job (gearbox swap, conveyor splice) can blow the average and should be timed separately.

Results at a glance

  • Required maintenance downtime: 148 min (headline result)
  • Base maintenance downtime: 120 min
  • Lock-out and delay allowance applied: 23 %
  • Technician completion rate: 0.2 pieces / min

Run it with your numbers

  • Every input above is editable in the live Maintenance Downtime calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.