Siemens SINUMERIK 840D sl Function Manual page 1371

The programmed D address refers to the active tool in relation to the master spindle (same as
for tool management function), when machine data is set:
MD20096 $MC_T_M_ADDRESS_EXT_IS_SPINO = TRUE (spindle number as address
extension).
Effect on the T number
If the "Tool management" function is active, the values programmed with reference to the
master spindle (or master toolholder) are displayed as programmed/active T numbers.
If tool management is not active, all programmed T values are displayed as programmed/
active, regardless of the programmed address extension.
Only the T value programmed in relation to the master spindle is shown as programmed/active,
when:
MD20096 $MC_T_M_ADDRESS_EXT_IS_SPINO = TRUE (spindle number as address
extension).
Example
The example below shows the effect of MD20096.
Two spindles are considered. Spindle 1 is the master spindle. M6 was defined as the tool
change signal.
T1 = 5
M1 = 6
T2 = 50
M2 = 6
D4
Basic Functions
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
W1: Tool offset
18.2 Tool
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