Zeiss CONTURA, Руководство по эксплуатации

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Preparation for measuring operation
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61211-1310402 CONTURA
2 Probing direction
5 Check the result.
The result is evaluated according to the standard deviation. There is
no maximum standard deviation which applies to all applications.
The toleranceable deviation depends on many factors: for example
resolution and precision of the CMM, length and rigidity of the stylus
shaft, quality of the stylus tip, cleanness of the environment. Nor-
mally, the standard deviation should be within a range of a few mi-
crometers
If the result is not satisfactory, repeat the qualification or look for
plausible causes. It may be necessary to decide whether or not to ac-
cept measuring inaccuracies.
Note: If measured values scatter despite good values for the stan-
dard deviation, or unexpected deviations occur, then you should
check the stylus system and replace it if necessary.
6 Repeat steps 2 to 4 for all other styli of the stylus system.
7 Qualify additional stylus systems if necessary.
In this case, repeat steps 1 to 5.
NOTE
If high precision is required or in case of high temperature variations,
the qualification procedure should be repeated regularly.
When the CMM has been in operation for several weeks without inter-
ruption and the same stylus systems are always required for measure-
ment, the stylus systems should be qualified at least once a week. For
requalification of already qualified styli, six probing points are sufficient.
Causes of large deviations
If large deviations occur during qualification, measuring inaccuracies will
be caused during subsequent measuring operation. In order to avoid
such inaccuracies, the mechanical design of the corresponding stylus
system should be checked.
Sources of errors
The sources of malfunctions and errors which may lead to increased de-
viations are listed below.
– Stylus system configuration
– Stylus status
– Magnetic field
– Influence of temperature