Write Online Tool Offset: Continuous - Siemens SINUMERIK 840D sl Function Manual

18.3.2

Write online tool offset: Continuous

FCTDEF
Certain dressing strategies (e.g. dressing roller) are characterized by the fact that the
grinding wheel radius is continuously (linearly) reduced as the dressing roller is fed in. This
strategy requires a linear function between infeed of the dressing roller and writing of the
wear value of the respective length.
Function FCTDEF allows 3 independent functions to be defined according to the following
syntax:
Function parameters
The function parameters are set in a separate block according to the following syntax:
FCTDEF(<polynomial no.>, <lower limit>, <upper limit>, <coefficient a0>, <coefficient a1>,
<coefficient a2>, <coefficient a3>)
FCTDEF
Polynomial no.:
Lower/upper limit:
Coefficients a
A 3rd degree polynomial is generally defined as follows:
y = a
Figure 18-11 Straight line equation
Note
FCTDEF must be programmed in a separate NC block.
Extended Functions
Function Manual, 09/2009, 6FC5397-1BP20-0BA0
W4: Grinding-specific tool offset and monitoring functions - only 840D sl
, a , a :
0 1 2
+ a * x + a * x + a
2
0 1 2 3
Function definition
Number of function (e.g. 1, 2 or 3)
Determines value range of the function
(limit values in input resolutions)
Coefficients of polynomial
* x
3
18.3 Online tool offset
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