If you are running a WATS Trial, your instance will normally be pre-populated with demo data to allow for a low-effort initial evaluation. If you are not able to see this data, please contact us at support@virinco.com and we will check that it has been uploaded.
The data covers two products, part numbers OLC-140-C and OLC-140-P.
There are about 1000 UUT Reports pre-loaded as historical data for the past two months, and approximately 2700 UUT Reports will be generated during the first three weeks of the trial.
Here are four good exercises you can start with to familiarize yourself with the environment and reporting capabilities.
Test Step Yield Analysis - Find most frequent failures.
Process Capability Analysis - Evaluating your test limits
Periodic Yield - Investigate presence of retesting
Test Reports - Locate a UUT report
Test Step Yield Analysis - Find most frequent failures.
From the login window, select Reporting to access the reporting interface. Select Yield Report from the panel to the left of the screen. Press Clear Filter to use the default filter settings (all data from last month) and select Apply. This will show you basic volume and yield statistics for the two products in their respective recorded test operations.
Click the Action Icon (thee grey lines) to the left of the OLC-140-C product. This will open up a list of possible drill-down reports for this set of data. Select Test Step Yield and Analysis.
You will now see that the filter parameters has been updated based on the product selection you made.
The secondary filter displays the available test sequence file versions, for you to select the relevant ones. If you don't see this secondary filter, press Apply.
Select both of these, and press Apply Selected.
This report will now show you a summary of the performance of each individual test step in your test sequence.
The first Pareto displays the maximum, minimum and average step time for each step, along with the accumulated average step time in percentage.
The second Pareto diagram shows you the failure rate of the different steps, displayed as number of occurrences and accumulated percentage of total failures. In the image below you can see that the VA-PowerLoad step has failed approximately 90 times, and represents around 30% of total failures.
Click on the blue bar representing VA-PowerLoad to drill down to the underlying measurements, shown in the Step Details View. As the data shows, all of the failures here are against the lower test limit (red line). The dark blue lines show three standard deviations for the displayed set of data.
You can group the measurements based on different meta parameters. Under Group By, select Operator, and use Grouped Line as X-Axis parameter for an alternative view.
Process Capability Analysis - Evaluating your test limits
From the login screen, select Reporting and Process Capability Analysis. Press Clear Filter to use the default filter settings (all data from last month) and select Apply. Select OLC-140-C from the secondary filter, and press Apply Selected.
This report will show you Process Capability information for your test measurements. There are two columns relevant to start with, the Cpk and the Cpk without failures. These are the process capability index numbers for all measurements, and for only the ones flagged as passed.
A red number is indicative of an underlying unstable measurement process, alternatively too tight test limits.
A green number is indicative of an acceptable process.
A blue number typically represents test limits that are too wide, thus contributing to poor test accuracy.
Navigate down the step named Test IO2 - Read Back Low. You can see that the Cpk for this is red, while the corresponding value without failures are blue. Press the rightmost magnifying glass to the left of this measurement to open up the Step Details View, displaying the underlying measurements.
In the first window, use the default selection and press Analyze Selected.
Locate the Failed Measurement Toggle, and move it to Hide. This will remove all measurements flagged as Failed. In the display below you can clearly see measurements that are far away from the average, but still within the test limits. You can hover your cursor above these to see information on the unit, and if you click it will open up the UUT Report for that unit.
Periodic Yield - Investigate the presence of retesting
From the login screen, select Reporting and then Periodic Yield. Press Clear Filter to use the default filter settings (all data from last month), then select PCBA (demo) under Test Operation in the upper right. Press Apply.
Expand a period in the selection by pressing the arrow to the left. Scroll down to the bottom of the report to see a graphical representation showing when units tested good actually passed. The example below shows that approximately 100 units passed in the second attempt. Approximately 25 passed in the third attempt, but there are also products that took 21 attempts to pass. You can click directly on the bars to open up Serial Number History for these units.
Test Reposts - Locate a UUT report
From the login screen, select Reporting and then UUT Report. Press Clear Filter to use the default filter settings, and select Apply Filter.
Locate a test report of interest, and press the magnifying glass to the left of it.
The upper right corner presents you the option of modifying the view, and users assigned with a Manager role can also modify the header content of the report.
The hierarchy in the report shows sequences, sub-sequences, measurements and multi-numeric measurements. You can click on a level to expand it, or use the Show/hide all button to expand the entire report.
If the selected test report is flagged as failed, the step flagged as Caused UUT Failed will be highlighted.
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