Fctdef - Siemens SINUMERIK 840Di sl Function Manual

Example 2
Alteration of a lead/delay time:
ID=1 WHEN $AA_IW[x] > 0
DO $$SN_SW_CAM_MINUS_TIME_TAB_1[0] = 1.0
Note
Software cams must not be set as a function of velocity via synchronized actions
immediately in front of a cam. At least 2-3 interpolation cycles must be available between the
setting and the relevant cam position.
2.4.4

FCTDEF

Application
The actions of online tool offset FTOC and polynomial evaluation SYNFCT described in the
subsections given below require an interrelationship between an input quantity and an output
quantity to be defined in the form of an polynomial. FCTDEF defines polynomials of this type.
For special examples of polynomial application for online dressing of a grinding wheel,
please see Subsection "Online tool offset FTOC". For examples of load-dependent feedrates
and clearance control via polynomials, please see Subsection "Polynonmial evaluation
SYNFCT".
Characteristics of polynomials
The polynomials defined by means of FCTDEF have the following characteristics:
• They are generated through a FCTDEF call in the part program.
• The parameters of defined polynomials are real-time variables.
• Individual polynomial parameters can be overwritten using the same method used to
Synchronized actions
Function Manual, 11/2006, 6FC5397-5BP10-2BA0
write real-time variables. Permissible generally in part program and in action section of
synchronized actions. See Chapter "Setting (writing) and reading of real-time variables".
Note
Validity limits and coefficients of existing polynomials can also be changed from
synchronized actions.
Example WHEN ... DO $AC_FCT1[1]= 0.5
Detailed description
2.4 Actions in synchronized actions
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