Siemens SINUMERIK 840D sl Function Manual page 47

Application
This function allows analog values to be output instantaneously by bypassing the PLC
cycles.
The analog NCK outputs are used in particular for grinding and laser machines.
Figure 1-4
Extended Functions
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
Signal flow for analog NCK outputs
Digital and Analog NCK I/Os (A4)
NCK I/O via PLC
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