What is OEE — and why is it so valuable?
OEE (Overall Equipment Effectiveness) is true plant availability — true because it summarizes all plant losses in a single key figure.
The three degrees of loss
Availability level: Should the system be running right now — and is it running? Anything that stops the system (faults, set-up, cleaning, missing parts) is recorded here as a loss.
Performance level: How much does the plant produce compared to what it could produce? The actual speed is measured in relation to the maximum speed.
Quality level: NIO parts and scrap tie up machine capacity, which is therefore lost. From a plant perspective, every out-of-spec part is a loss — regardless of whether it is reworked or ends up as scrap.
The coffee machine example
The three degrees can be explained vividly in everyday life. Imagine an office coffee machine where several people want to make coffee one after the other — target time: 50 seconds per cup.
Loss of availability: Before the first cup runs, the pomace must be changed. The machine is standing — downtime.
Power loss: After the first coffee, the group talks, the next cup is not started immediately. 10 seconds delay — loss of performance.
Quality loss: The third person does not adjust the mug correctly, the coffee runs next to it — loss of quality.
Why is OEE such a strong indicator?
Freedom from manipulation: If downtimes are not correctly recorded, they automatically appear in other loss areas. The losses don't disappear — they are just allocated differently.
Cause transparency: The OEE not only shows how well a system is running, but also where the problem lies — availability, performance or quality. This is the basis for targeted measures in the continuous improvement process.