Selecting a Unit Serial Number After Inspection Data Step
There are three known possible symptoms. Firstly parts are noticeably failing but the failure counter is not being incremented. Secondly the user has chosen to only save failed data, but no data is being saved. Thirdly the Switch on Unit Status always chooses the passed even though the part failed.
Cause:
The original design of the software made the assumption that the serial number (either Bar Code Scan or Automatic) step would be one of the early steps in the production line sequence. Therefore the serial number step is also used to clear some of the failure accumulators for the production line. These cleared accumulators affect how the Update Pass/Fail Status, Switch on Unit Status and the Save Data steps function. If the production line sequence has been setup so that the serial number step follows the Inspect Data step, then each of these three step types will not function properly when included after the serial number step.
Resolution:
In general try and keep your serial number steps before the Inspect Data step. If you must put the serial number step after the Inspect Data step then you must be aware of the following limitations.
The Update Pass/Fail Status step must be located between the inspection and serial number steps otherwise it will count every unit as passed.
The Switch on Unit Status step must be located between the inspection and serial number steps otherwise it will always select the passed switch.
The Save Data must be located after the serial number step, otherwise the data in the database will always be one serial number behind. Also the Save Data step will ignore the Save Rejected Units checkbox. Selecting the Store Accepted Units check box will cause all data to be stored and deselecting it will cause no data to be stored.