Siemens Sinamics S120 Function Manual page 467

● Any pending STOP F or STOP A commands are canceled (see r9772 / r9872).
● The messages in the fault memory must be additionally reset using the general
Restart after the "Safe Torque Off" function has been selected
1. Deselect the function.
2. Issue drive enable signals.
3. Cancel the "switching on inhibited" and switch the drive back on.
Status for "Safe Torque Off"
The status of the "Safe Torque Off" (STO) function is displayed using the parameters r9772,
r9872, r9773 and r9774.
As an alternative, the status of the functions can be displayed using the configurable
messages N01620 and N30620 (configured using p2118 and p2119).
Response time for the "Safe Torque Off" function
For the response times when the function is selected/deselected via input terminals, see the
table in "Response times".
Internal armature short-circuit with the "Safe Torque Off" function
The function "internal armature short-circuit" can be configured together with the "STO"
function. However, only one of the two functions can be selected, as an OFF2 is also always
triggered when STO is selected. This OFF2 disables the function "Internal armature short-
circuit".
The "STO" safety function has the higher priority when simultaneously selected. If the "STO"
function is initiated, then an activated "internal armature short-circuit" is disabled.
Drive functions
Function Manual, (FH1), 01/2012, 6SL3097-4AB00-0BP2
acknowledgement mechanism.
Note
If "Safe Torque Off" is selected and deselected through one channel within the time in
p9650/p9850, the pulses are suppressed without a message being output.
However, if you want a message to be displayed, then you must reconfigure
N01620/N30620 as an alarm or fault using p2118 and p2119.
– 1/0 edge at input signal "ON/OFF1" (cancel "switching on inhibited")
– 0/1 edge at input signal "ON/OFF1" (switch on drive)
Safety Integrated basic functions
9.4 Safe Torque Off (STO)
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