Siemens sinumerik 840D sl Function Manual page 425

Activating
The setpoint is exchanged and the corresponding interface signals are evaluated in the PLC
user program.
Note
An existing PLC user program may need to be modified due to changes in the meaning of
interface signals in comparison with the technology card solution.
Only one of the machine axes with the appropriate logical drive number may have control via
the setpoint channel of the drive at any one time.
Requests to transfer drive control are sent using NC/PLC interface signal:
DB31-..., DBX24.5 (change setpoint output assignment)
The current status of drive control is displayed in the NC/PLC interface signal:
DB31, ... DBB96.5 (setpoint output assignment)
Access rights to the shared drive must be managed in the PLC user program.
Transfer conditions
• Axis standstill of all axes involved.
• Special functions such as reference point approach, measuring, travel to fixed stop,
• No sign-of-life error and no faults pending on PROFIBUS drive.
The PLC interface provides constant information about the current state of the exchange. At
any one time, only one axis has drive control DB31, ... DBX96.5=1.
During exchange, servo enables on all axes involved are automatically withdrawn by the
controller.
Axes without drive control are not in closed-loop control. Therefore, a brake control must be
set up for vertical axes.
Special cases
If a number of transfer requests are made simultaneously, exchange will not take place. The
last axis used remains in control of the drive. This is also the case if there are no transfer
requests pending.
If there are no transfer requests during machine power-up, drive control is assigned to the
first machine axis located with the same logical drive number. Logical drive numbers are
scanned in ascending order.
MD30110 $MA_CTRLOUT_MODULE_NR[0,AX1] = 1
MD30110 $MA_CTRLOUT_MODULE_NR[0,AX2] = 2
MD30110 $MA_CTRLOUT_MODULE_NR[0,AX3] = 3
MD30110$MA_CTRLOUT_MODULE_NR[0,AX4] = 4 ; Drive control during power-up
MD30110 $MA_CTRLOUT_MODULE_NR[0,AX5] = 4
Special functions: Setpoint Exchange (S9)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
function generator, star/delta changeover, drive parameter set changeover are not active
in the axis with drive control.
Detailed description
2.1 Function
9