====== 10. OEE Calculation Reference ======

This chapter documents exactly how CedarInsight computes its figures, so every displayed value can be audited. All analysis views, reports and the AI Assistant use the same calculation functions; figures are consistent everywhere.


===== 10.1 Data captured per production run =====

^ Quantity ^ Source ^
| **Actual quantity** (units in) | Input-stage counter × units-per-count [[pinebox:01_manual|[PBX]]] |
| **Good quantity** (units out) | Output-stage counter × units-per-count [[pinebox:01_manual|[PBX]]] |
| **Defect quantity** | Defect/Reject-stage counter; can be corrected by the operator at run end ([[cedar-insight:manual:05-live-operation#run-end_summary_and_bad_parts|5.2.4]]) |
| **Target quantity** | Entered at changeover |
| **Running time** | Total time in states //Running// and //Running Slow// (from state events) |
| **Unplanned downtime** | Total time in state //Down// |
| **Planned production time** | Wall-clock run duration (start → end) |
| **Ideal cycle time** | From the product (or program default) configuration |

===== 10.2 Availability =====

<code>
Availability = Running time / (Running time + Unplanned downtime)
</code>

Availability relates run time to operating time. Time in //Planned Stop//, //Changeover// and //Draining// is not an availability loss, only unplanned //Down// time reduces Availability. This follows the standard OEE definition in which planned stops are excluded from the loss calculation.

===== 10.3 Performance =====

<code>
Performance = (Ideal cycle time × Actual quantity) / Running time
</code>

Performance compares the time the production //should// have taken at ideal speed with the time it actually ran. Slow cycles and minor stops (shorter than the stage timeout) reduce Performance. The value is capped at 100%.
<WRAP info>
Performance is only as accurate as the configured **ideal cycle time** ([[cedar-insight:manual:07-line-configuration#products|chapter 7.2]]).
</WRAP>
===== 10.4 Quality =====

<code>
Quality = Good quantity / Actual quantity
</code>

Good quantity is the output-stage count; actual quantity is the input-stage count. Operator corrections of the defect quantity at run end are reflected here.

===== 10.5 OEE =====

<code>
OEE = Availability × Performance × Quality
</code>

===== 10.6 Aggregation across runs =====

When several runs are combined (period views, grouping by product/program, reports), the factors are weighted, not simply averaged:

^ Factor ^ Aggregation ^
| **Quality** | Volume-weighted: Σ good / Σ actual over all runs |
| **Availability** | Time-weighted: Σ running / Σ (running + unplanned downtime) |
| **Performance** | Running-time-weighted mean of the per-run values, mathematically equal to Σ (ideal cycle × count) / Σ running time |
| **OEE** | Recomputed from the three aggregated factors: A × P × Q |

This means a long run influences the aggregate more than a short one; a simple arithmetic mean of run OEEs would distort the result.
===== 10.7 OEE colour scale =====

OEE values are colour-coded throughout the application. The default bands:

^ Band ^ Default threshold ^ Colour ^
| Excellent | ≥ 85 % | dark green |
| Good | ≥ 75 % | light green |
| Fair | ≥ 60 % | yellow |
| Poor | ≥ 40 % | orange |
| Critical | < 40 % | red |

The thresholds are configurable under //System → System → OEE Thresholds// ([[cedar-insight:manual:09-system-administration#system_configuration|chapter 9.1]]).