Siemens SINAMICS S120 Function Manual page 59

Figure 5-1 Terminals for "Safe Torque Off", example for Motor Modules Booksize and CU320
Grouping drives (not for CU310)
To ensure that the function works for more than one drive at the same time, the terminals for
the corresponding drives must be grouped together as follows:
● 1. Switch-off signal path (CU320)
● 2. Switch-off signal path (Motor Module/CUA31)
The assignment is checked during the test for the switch-off signal paths. The operator
selects "Safe Torque Off" for each group. The check is drive-specific.
Example: Terminal groups
It must be possible to select/deselect "Safe Torque Off" separately for group 1 (drive 1 and
2) and group 2 (drive 3 and 4).
For this purpose, the same grouping for "Safe Torque Off" must be performed on both the
Control Unit and the Motor Modules.
Safety Integrated
Function Manual, (FHS) , 07/2007 Edition, 6SL3097-2AR00-0BP0
By connecting the binector input to the joint input terminal on the drives in one group.
By appropriately connecting-up the terminals for the individual Motor Modules/Power
Modules belonging to the group with CUA31.
Note
The grouping must be identical in both monitoring channels.
If a fault in a drive results in a "Safe Torque Off (STO)", this does not automatically mean
that the other drives in the same group also switch to "Safe Torque Off (STO)".
5.2 Control via terminals on the Control Unit and the power unit
Control of the safety functions
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