Safe Direction (Sdi); Selecting And Deselecting Sdi - Siemens SINAMICS G120 Function Manual

Description

2.6 Safe Direction (SDI)

2.6 Safe Direction (SDI)
Using the safety function SDI, the inverter prevents that the motor shaft rotates in the wrong
direction.
Figure 2-18
2.6.1

Selecting and deselecting SDI

If you select SDI , then the inverter only permits the selected motor direction of rotation after
the delay time expires.
Note
If the motor rotates in the wrong direction when SDI is selected, then the inverter normally
brakes the motor with the OFF3 ramp-down time (parameter p1135). If you do not want that
the inverter automatically brakes the motor, then you must disconnect the interconnection
between the "SDI" function and the ramp-function generator of the inverter: p1051 = 9733 →
1083 and p1052 = 9733 → 1086.
If the motor does not automatically brake the inverter, then the machine control must ensure
that the motor speed lies below the monitoring threshold in sufficient time.
The inverter tolerates brief movement in the monitored direction of rotation, by converting the
motor speed into a distance (position). With the tolerance p9564 , you specify the maximum
permissible position.
42
Basic principle of operation of SDI
Safety Integrated Function Manual, SINAMICS G120 and G120C
Function Manual, 01/2011, FW 4.4, A5E03052391B AB