Zeiss CONTURA, Operating Instructions Manual

Page: 113 / 158

Preparation for measuring operation
61211-1310402 CONTURA
7-17
Influence of temperature
The stylus is inserted manually and qualified immediately. Due to the
heat of the hand, the temperature of the probe material and the mate-
rial properties change as a result thereof. Minor differences in tempera-
ture already influence the material properties. The effect depends on the
stylus system components. For the temperature effect to be as low as
possible, wear gloves while handling the stylus system and insert it into
the adapter plate receptacle
See also
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➤
Causes of scattering and measurement errors [
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7-23]
Temperature compensation
What is temperature compensation?
The measuring software calculates the workpiece geometry for the ma-
terial properties at 20 °C. 20 °C is the reference temperature for length
measurements according to DINENISO1. Since the actual temperature
deviates from the 20 °C, the geometric data have to be corrected by a
correction value.
Expansion coefficient The correction value is calculated by the measuring software. However,
the measuring software needs to know the temperature of the CMM
and the workpiece. Furthermore, the expansion coefficient must be en-
tered in the measuring software. See operating instructions for the mea-
suring software.
We can differentiate between two cases:
Case 1: No temperature sensor can be connected to the CMM.
1. Determine the temperature of the workpiece.
2. Enter the temperature of the workpiece and the ex-
pansion coefficient for the workpiece material in the
measuring software.
The measuring software calculates the correction value.
Case 2: Connecting a temperature sensor to the CMM is possi-
ble.
1. Enter the expansion coefficient for the workpiece ma-
terial in the measuring software.
2. Connect the temperature sensor.
The measuring software calculates the correction value.