Siemens SINUMERIK 840D sl Function Manual page 351

Coefficient tanβ (T)
In order to determine the dependency of coefficient tanβ of the position-dependent
temperature compensation on the temperature, the error curve gradient is plotted against the
measured temperature:
Figure 5-3
With the appropriate linearization, coefficient tanβ depends on T as follows:
tanβ(T) = (T - T
with
T = temperature at which position-dependent error = 0; [degrees]
0
T
max
TK
max
Therefore, based on the values from the above diagram:
T = 23°
0
T
max
TK
max
and tanß (T) is therefore:
tanβ(T)
Example:
At a temperature of T = 32.3 degrees, therefore: tanβ = 0.000132
PLC user program
The formula given above must be used in the PLC user program to calculate the coefficient
tanβ (T) which corresponds to the measured temperature; this must then be written to the
following NCK setting data:
SD43910 $SA_TEMP_COMP_SLOPE (gradient for position-dependent temperature
compensation)
According to the example above:
SD43910 $SA_TEMP_COMP_SLOPE = 0.000132
Extended Functions
Function Manual, 09/2009, 6FC5397-1BP20-0BA0
Characteristic of coefficient tanβ as a function of measured temperature T
) * TK * 10
0 max
= maximum measured temperature; [degrees]
= temperature coefficient at T
= 42°
= 270 µm/1000 mm
= (T - 23) [degrees] * 270 [µm/1000 mm] * 10
= (T - 23) [degrees] * 14.21 [µm/1000 mm] * 10
/ (T T )
-6
max - 0
; [µm/1000 mm]
max
K3: Compensation
5.2 Temperature compensation
/ (42 - 23) [degrees]
-6
-6
351