12.4
Restart Lock Procedure
The following diagram shows the restart lock procedure by means of a time axis, includ-
ing the required steps that must be performed in order to be able to restart the device
after an activated restart lock.
Fig. 59: Behavior STO / restart lock - timing and required actions
Use case A
If an STO contact is interrupted during “Switch off”, the device status “Switch on dis-
abled” is triggered. As soon as the STO contact is closed again, the drive can restart
with the next “Switch on”.
Use case B
If an STO contact is interrupted during “Switch on”, the device status “Error” is trig-
gered. The error must be confirmed via an error reset to continue operation.
105
Drive System SD2M - Hardware Description 036228xxF
Safety Circuit / Restart Lock (STO)
STO
function
acc. to
EN ISO
13849-1:2008-12,
DIN EN 62061:2005
SIL
3
not
possible
