4.3.2.2 Batch Statistics On-Line Analysis
Setting Up Batch Statistics
From the 'Set-up' menu, select 'Results' to see the following dialogue:
Select 'Display Basic Statistics' to save results to a database. For this
feature to operate a licence for use must first be obtained from your
Voltech supplier.
All results formats can be saved simultaneously.
Basic statistics displays, on-line, a summary of the results for the
current batch of transformers that is being tested on every AT connected
to the Server. Results for previous batches can also be opened and the
statistics displayed and printed.
The batch statistics window display is automatically shown once this
feature is enabled. For each AT connected to the Server the following
information is displayed:
The type of AT and its serial number, and the part name, operator and
batch.
PASS or FAIL for the last part tested, the total tested so far and the
serial number of the last part tested.
The number that have passed and failed, and the AQL<+> (Acceptable
Quality Level) of the transformer.
The number of re-tries that have been attempted, the percentage of
failures so far and the number of transformers that failed out of the last
10 tested.
For each test in the program, the test limits, the last result and the
accumulated number of fails for each test.
Results may also be exported or printed using the normal options found
under the file menu.
AQL
AQL (Acceptable Quality Level) settings for production test are defined
for each program using the Editor. AQL is the level of test failures in a
batch that are acceptable. Exceeding the AQL is an indication that there
is problem with the quality of the production process or the quality of
materials used. AQL monitoring is an optional feature of the Voltech PC
Server which displays live summary results from multiple AT testers. When
the AQL level set here is reached or exceeded, the Server will display a
warning.
'AQL No. of Parts' is the number of failures in the batch at which a
warning will be displayed on the Server. This is most often used when the
batch size is always similar, or zero / very small numbers of defects are
expected.
'AQL % of Parts' is the percentage level of failures at which a warning
will be displayed on the Server. Note that this AQL is only applied after
sufficient parts have been tested to make the percentage meaningful. When
setting AQL % of Parts to be 1% for example, a warning will only be
displayed after 100/1 = 100 parts have been tested.
Both types of limit may be used at the same time. Reaching any one limit
will cause a warning to be displayed on the Server.
When an AQL level is reached or exceeded the Server will display a
warning:
Click on 'OK' to acknowledge the warning. You will be given the option to
disable the warning for further parts in the batch. Normally, you would
select 'No' to leave the AQL checking active for the rest of the batch.
When a new batch is started, the AQL level is reset according to the level
entered for the part using the Voltech AT Editor.