Explains how sample size (field QALS-GESSTICHPR) is calculated during inspection lot creation.
This document introduces what settings influence sample size calculation and the logic about how the sample size is determined during lot creation.
- Plant level:
In the customizing t-code QCC0 -> Quality Management -> Basic Settings -> Maintain Settings at Plant Level, tab “Insp. lot creation”, there are some fields called presettings for sampling procedures. These settings are used automatically if no sampling procedures are defined in the characteristics.
- Material level:
In the QM view of material master (t-code MM01/MM02/MM03), for each inspection type, there are several fields and indicators which control sample size calculation. The logic will be explained later.
- Characteristic level:
If you set the control indicator “sampling procedure” for the characteristic, a sampling procedure has to be assigned to an inspection characteristic in a task list or material specification..
If you do not enter a sampling procedure for an inspection characteristic, the system chooses a sampling procedure proposed in the settings at plant level. If no sampling procedure was entered in these settings, the system takes the lot size as the sample size.
A sampling procedure can be created in t-code QDV1.
Four sampling types can be used:
- Sampling type 100 – Fixed sample
You need to enter a fixed number as sample size.
- Sampling type 200 – 100% inspection
As described it uses lot size as sample size.
- Sampling type 300 – Use sampling scheme
A sampling scheme and its severity need to be entered to calculate sample size.
- Sampling type 400 – Percentage sample
Enter a percentage to calculate sample size.
The sampling types are defined in the customizing t-code QCC0 -> Quality Management -> Basic Data -> Define Sample Determination. You can read the documentation here to know more.
There are two possibilities for determining the sample size:
- The sample size is entered by the user
If the sample size is to be entered manually during the inspection, you must set the indicators “Manual sample entry” and “Manual sample calc.” in the material master. Please note the indicator “Manual sample entry” is only taken into account for an inspection that is carried out without a task list or material specification.
- The sample size is calculated automatically by the system
If the sample size is to be calculated automatically, a distinction must be made between the following two cases:
- Inspection without an inspection plan or material specification
To calculate the sample size, you can set the fields “sampling procedure” or “inspection percentage” in the material master. They are only relevant, when you carry out an inspection without reference to a task list or material specification.
The indicator “100% inspection” can also be set in the material master. See the F1 help of this field to know more about this indicator. The note 213505 explains why sample size is 1 although this indicator is set.
- Inspection with an inspection plan or material specification
The sample size is calculated on the basis of the sampling procedure defined at the characteristic level of the inspection plan or material specification.
If a sampling procedure was not defined in the inspection plan or material specification, the system uses the predefined sampling procedure stored in customizing at plant level to determine the sample size.
If a sampling procedure is not specified in Customizing, the lot size is used as the sample size for the characteristic.
- If you set the indicator for a 100% inspection in the material master record, this has priority over all other procedures defined to calculate the inspection size.
- If several characteristics use different sampling procedures, the highest sample size of the characteristics is used as the inspection lot sample size.
- The following document introduces how sample drawing procedure influences the lot sample size in physical sample management.
Physical Samples Management in SAP QM
QAC3 – Reset sample calculation
Related SAP Notes/KBAs
213505 - Sample size 1 for 100% inspection
372271 - Sample size 0 for inspection lot creation
1853950 - Sample size displays 32,767 in transaction code QE11