Siemens SINUMERIK 840D sl Function Manual page 1689

Setting via FC18 synchronized actions
If the constant cutting rate is set via FC18, the setting of bit 6 in byte to in the "Signals to
concurring positioning axes" area determines how the speed value (bytes 8...11) is
interpreted.
In the case of setting via synchronized actions, the feedrate type will determine how the S
value is interpreted, analogously to the part program.
Reading from part program and synchronized actions
The programmed cutting rate value can be determined both in the part program and in
synchronized actions by reading system variables:
$P_CONSTCUT_S
and
$AC_CONSTCUT_S.
The programmed cutting rate value can also be read via the OPI interface.
System variables
RV: Defined range of values of the two new system variables.
Description
Last constant cutting rate programmed
RV = {0, DBL_Max}
Current constant cutting rate
RV = {0, DBL_Max}
Basic logic functions: Spindles (S1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Detailed Description
2.5 Programming
NCK variable
$P_CONSTRUCT_S[n]
$AC_CONSTRUCT_S[n]
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