The downtime causes defined in PC-Topp have different effects on the calculation of times in the PC-Topp production statistics.
These effects are best explained by taking a look at the basic hierarchical concept for calculating production times in PC-Topp.
| Category | Abbr. | Definition |
| Available Shift Hours | ASH | Shift duration, e.g. 8’00
plus any overtime after the beginning or before the end of the shift. |
| Machine Shutdown Hours | MSH | In case of shorter shift duration Machine Shutdown Hours explain the difference between shorter Open Hours and Available Shift Hours. |
| Open Hours | OH | The total period of time during which a machine is open
(Available Shift Hours minus Machine Shutdown Hours) |
| Break Hours | BH | Total time of breaks |
| Scheduled Downtime Hours | SDH | Total scheduled downtime |
| Work Hours | WH | Open Hours minus Break Hours minus Scheduled Downtime Hours |
| Set-Up Hours | SH | Set-Up Hours including downtimes during set-up |
| Run Hours | RH | Run Hours including downtimes during run |
| Downtime Hours | DH | The time taken up by breakdowns (including Mini Downtimes and times unaccounted for which are treated the same as Mini Downtimes). |
| Downtime Hours during Run | DHR | Downtime Hours during run |
| Downtime Hours during Set-Up | DHS | Downtime Hours during set-up |
| Production Hours | PH | Work Hours minus Downtime Hours |
| Net Set-Up Hours | NSH | Set-Up Hours minus Downtime Hours during set-up |
| Net Run Hours | NRH | Run Hours minus Downtime Hours during run |
The following diagrams illustrate how the PC-Topp times are based on each other.
Focus on Stopped Time and Machine Productive Time
Here the PC-Topp times are visualized by stripping away one after the other of the different stopped times from the machine’s available time. The final result is the time during which the machine actually produces goods.
Focus on Downtimes during Run and Set-Up
Downtimes can occur during set-up and run. Therefore in this diagram the Work Hours are divided into Run Hours and Set-Up Hours which are again subdivided into Net Set-Up and Run Hours vs. Down Hours during Set-Up and Run.
This is necessary to determine the time during which the machine actually runs without interruption by downtimes. Of course the Down Hours during Set-Up and Run equal the Down Hours in the above chart.
The above times are the basis for calculating speeds in PC‑Topp: The Run Hours can serve as a reference value for estimating the Planning Speed (used to compute how long an order will run). Speeds calculated using the Net Run Hours offer a guideline for a realistic machine Target Speed.