Festo Checkbox Compact CHB-C-C, Руководство пользователя

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6. Testing parts
6-6
Festo P.BE-CB-COMP-EN en 0211a
6.3 Influence of the tolerance
Bandwidth When a new parts type is taught, the features of all scanned
parts are recorded. The values of the registered features
differ individually from each other. For each feature there is a
value range (bandwidth) in which test parts are graded as
“Good.” By means of the tolerance setting, you can extend
this bandwidth. Test parts, the features of which lie within the
band width of the sample part or in the tolerance range bor-
dering onto this, will still be accepted as good parts.
With 0 % tolerance, parts will only be accepted as good parts
if their features of which lie exactly within the band width of
the scanned sample parts. Set at least 1 % tolerance. You can
then be sure that good parts are correctly classified despite
minimum position deviations.
Setting the tolerance The setting must be made in the stop status.
1. Press the START/STOP button: Stop status.
2. Press and hold down the START/STOP button.
3. Increase the tolerance with the TEACH/STATUS button:
setting range 0...20 %
standard setting 5 %
recommendation at least 1 %.
4. Release the START/STOP button.
The value selected will automatically be added to the data of
the parts type and saved.
Optimization Ascertain in test mode the optimum setting of the tolerance,
especially with critical parts. Use one of the following
methods:
S
Empirical setting:
Vary the tolerance so that the test of a large number of
parts produces correctly recognized good and bad parts.