Deselection Of The Function - Siemens SINUMERIK 840C Installation Instructions Manual

12.93 12 Functional Descriptions
12.24.5 Travel to fixed stop with programmable clamping torque
The NC setpoint interface then begins to output the current setpoint defined in NC MD 1144*.
The NC outputs the interface signal FIXED STOP REACHED to the PLC.
The PLC then activates terminal E5 of the actuator, thus effecting a switchover from speed-
controlled to torque-controlled operation. After a time period of > 80 ms, the PLC switches off
the torque limitation (by selecting the preceding gear stage). In addition, the PLC also sends
an edge signal ACKNOWLEDGEMENT FIXED STOP REACHED to the NC.
The NC subsequently deletes the remaining distance to go and switches the C-axis to follow-
up mode.
The C-axis setpoint output now outputs the current setpoint in accordance with the specified
torque (SD 320*).
A block change is then performed. The current setpoint, and thus also the clamping torque,
remain applied.
12.24.6

Deselection of the function

The NC detects that the function has been deselected on the basis of G220 and inputs a "0"
current setpoint, i.e. it no longer specifies a clamping torque.
It resets the interface signals TRAVEL TO FIXED STOP ACTIVE and FIXED STOP REACHED,
cancels follow-up mode and the read-in enable command.
The PLC must then switch the drive to speed-controlled operation. In addition, any current
limitation which may still be applied must be deactivated (terminal 96 with SIMODRIVE 611A,
gear stage selection with SIMODRIVE 611A MSD or 660).
If a traversing motion is programmed in the deselection block, then the motion will be
executed.
The NC issues the read-in enable command again and performs a block change.
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SINUMERIK 840C (IA)