Lighting, LEDs & Electrical Fixtures worked example

Burn-In Test Capacity at 63% chamber uptime: a worked example in lighting, leds & electrical fixtures

Here is what the math looks like when conditions slip. We hold every other input steady and drop chamber uptime to 63%, then walk the calculation through step by step. Calculate the effective burn-in test capacity for LED luminaires per shift by combining rack positions, available test cycles, oven or chamber uptime, and the percentage of fixtures passing burn-in without failure.

The inputs for this scenario

  • Fixture positions per rack cycle: 48 fixtures / cycle (held at the documented default)
  • Available burn-in cycles per shift: 4 cycles (held at the documented default)
  • Chamber uptime: 63 % (the input this scenario stresses; the baseline uses 88)
  • Burn-in first-pass yield: 98 % (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Gross burn-in capacity = fixture positions per cycle x cycles per shift.
  • Good fixtures cleared per shift works out to 119 fixtures at these inputs, and this is the headline figure for the scenario.
  • Gross burn-in test capacity works out to 192 fixtures at these inputs.
  • Fixtures lost to chamber downtime works out to 71.04 fixtures at these inputs.
  • Fixtures failing burn-in works out to 2.42 fixtures at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where chamber uptime sits at 88% and the headline result is 166 fixtures, this scenario comes in 28.41% below the baseline at 119 fixtures.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to chamber uptime, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. It assumes full racks every cycle and a constant yield; partial loads, mixed fixture dwell times, and units sent for rework rather than scrap will change the real good-out figure.

Results at a glance

  • Good fixtures cleared per shift: 119 fixtures (headline result)
  • Gross burn-in test capacity: 192 fixtures
  • Fixtures lost to chamber downtime: 71.04 fixtures
  • Fixtures failing burn-in: 2.42 fixtures

Run it with your numbers

  • To rerun this with your own numbers, open the live Burn-In Test Capacity calculator, set chamber uptime to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.