Cycle Time Standards¶
A Cycle Time Standard is the time one piece should take on a given machine. It's the yardstick Performance is measured against — without one, Performance can't be worked out at all.
Setting these up is an engineer's job.
What a standard holds¶
| Field | Description |
|---|---|
| Machine or Line | What the standard describes. Set one or the other, never both — a machine standard measures that machine, a line standard measures the whole line |
| SKU | The product this standard applies to |
| Ideal Cycle Time | How long one piece should take under ideal conditions |
| Setup Time (min) | Optional — changeover time before the run proper begins |
| Operation Sequence | Optional — which operation this is, where a product passes through the same machine more than once |
Ideal, not average
The ideal cycle time is the best sustained rate the machine can achieve for that product — not the average it currently manages. Setting it to the current average guarantees a Performance near 100% and hides exactly the losses the measure exists to reveal.
Changing a standard¶
Standards are versioned rather than overwritten. Adding a new standard for the same machine, product and operation supersedes the previous one from that point onward; the old version stays attached to the periods it applied to.
This means improving a standard never rewrites past performance figures. Last quarter's Performance continues to be measured against the standard that was actually in force at the time, which is what makes comparing quarters meaningful.
Only the current standard for each machine and product is listed. Use a row's History action to see every version it has had — each one's effective date, its cycle and setup times, and which is in force today.
Deleting a standard¶
A standard that has never been used can be deleted with the bin icon. One that production counts already reference cannot be deleted — Enture will say so, because removing it would leave those counts pointing at a standard that no longer exists. Supersede it instead by adding a new one, which is what the versioning is for.
When Performance can't be worked out¶
If a machine and product pair has no active standard, the OEE figures show Availability and Quality, and Performance is left blank with an explanation. This is the most common reason for a blank Performance.
A line needs its own standard
A machine standard is never used to measure a line, and vice versa — they describe different things, and a line's rate is not the sum or the average of its machines'. So if line OEE shows a blank Performance, add a standard scoped to that line; adding one for a machine on it won't do.