Sampling is the practice of randomly selecting products and sending them for inspection. This can be done do ensure that a consistent quality is maintained.
Sampling occurs after an operation is completed and the operator has pressed the operator switch. Buffer operations and unloading operations are by their nature excluded from sampling.
Sampling can be set at the following points
- Operation
- Operation Group
- User
- User Group
For every sampling point, a sampling rate (in %) and sampling route is configured. The route should be an Inspection Route. For the sampling point to be considered active, both a rate > 0% and route must be set.
When there is only one possible sampling point, the calculation is easy. The % chance that a product goes on sampling is the value of that one point, e.g. Operation Sampling 50% => 50% chance that this product is sent to sampling.
When multiple points are active at once, the highest % sampling value of any one point is used to determine if the product should go on sampling or not.
For example
Operation Sampling = 10%
Operation Group Sampling = 40%
Total chance that this carrier will go on a sampling route is the highest %, which is 40%, otherwise it will continue on the normal route.
Which of the sampling routes it will take is calculated by combining the % of all the points, and scaling that to 100%. In the example above:
10% + 40% = 50%
Scale so that target = 100%
20% + 80% = 100%
Once we have determined that the sampling will be performed, the chance of the product going on the Operation sampling route is 20% and Operation Group sampling route 80%.
Combine these two checks and the chance that the carrier will go on the Operation sampling route is 20% * 40% = 8%, Operation Group sampling route = 80% * 40% = 32%, and no sampling performed at all = 60%.
The scaling works the same way of the total sum > 100%
Operation Sampling = 50%
Operation Group Sampling = 50%
User Sampling = 50%
User Group Sampling = 50%
50% + 50% + 50% + 50% = 200%
Scale so that target = 100%
25% + 25% + 25% + 25% = 100%
Once the initial check of sampling or not is done at 50%, the chance of the product going on either of the sampling routes is 25%
Combined, the chance for either of the samplings to happen is 25% * 50% = 12,5%