Siemens SINUMERIK 840D sl Commissioning Manual page 119

In the channel-specific machine data, for at least one geometry axis per channel enter a
value other than 0.0, e.g. 0.001. If the value is 0.0, the system assumes that this parameter
has still not been set.
MD53230 $MCS_SIM_START_POSITION
Simulation is only possible if a value not equal to 0 has been set for at least one geometry axis.
Note
Program start in the simulation
If MD22622 $MCS_DISABLE_PLC_START is set in a channel, then the channel is not
automatically started in the simulation. It can then only be started from another channel
using the part program command "START".
Note
Alarm display in the simulation
Alarms are output in the simulation exactly the same way as alarms in the normal program
execution, but no more than five alarms are displayed (above the graphic, to distinguish
them from the machine alarms).
If a different error signaling behavior (e.g. syntax error) occurs between simultaneous
recording and simulation, then, for example, the reason can be due to the hardware access
operations in the programming. The simulation does not access the hardware, however,
internally it reads the input with 0 and is then exited. On the other hand, for simultaneous
recording, an alarm is output.
Deactivating simulation
The following machine data must be set to deactivate the simulation:
MD51226 $MNS_FUNCTION_MASK_SIM
Bit 1 = 1
SINUMERIK Operate (IM9)
Commissioning Manual, 03/2013, 6FC5397-1DP40-3BA1
Software option
You require the following option for further simulation settings:
"3D simulation 1 (finished part)".
Deactivating simulation
Simulation and simultaneous recording
9.2 Configuring the simulation
Axis position when starting the simulation
Simulation function screen
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