Operating Instructions

Safe Torque Off Function
Reset the Parameter Settings
381 | 443
PFD
av
Probability of dangerous failure on demand
IEC61508
5.99 × 10
-6
PTI
Proof test interval
IEC61508
1 year
Category
Category
ISO13849-1
Category 3
PL
Performance level
ISO13849-1
d
MTTF
d
Mean time to dangerous failure
ISO13849-1
High
DC
Diagnostic coverage
ISO13849-1
Low
Table 17-3: Relevant safe loop parameters.
Reset the Parameter Settings
Use Pr.06-44 to specify the reset method when an STO alarm occurs.
~
STO Latch Selection
Default: 0
Settings
0: STO Latch
1: STO No latch
Pr.06-44=0: STO Alarm Latch. After you clear the cause of the STO Alarm, use a Reset command to clear the STO
Alarm..
Pr.06-44=1: STO Alarm no Latch. After you clear the cause of the STO Alarm, the STO Alarm clears automatically.
All of STL1–STL3 errors are “Alarm Latch” mode (in STL1–STL3 mode, the Pr.06-44 function is not available).
Timing Diagram Description
The following timing diagrams show the status of relevant signals under different conditions.
Normal operation status
As shown in the figure below, when S1–DCM and S2–DCM is ON (STO function is not required), the drive
executes Operating or Output Stop according to RUN command.