6.3
Safe Torque Off (STO)
6.3.1
Overview
What can you find in this Chapter?
The relevant operating cases for the STO function are described in this chapter.
Table 6-1
Operating cases for the STO function when the motor is switched on (ON/OFF1 = 1)
Selecting and de‐
selecting STO
Selecting and deselecting STO when the motor is switched on (Page 224)
Discrepancy in
the input signal
The fail-safe digital input to select STO identifies an error.
Response to a discrepancy when STO is active (Page 226)
Table 6-2
Switching the motor on and off when STO is active or not active
Switching on the motor (ON/OFF1 =
0 → 1)
Switching off the motor (ON/OFF1,
OFF2 or OFF3 = 1 → 0)
STO is not active If STO is not active, then there are no restrictions for switching on and switching off
the motor.
STO is active
The active STO function prevents the
motor from being switched on.
The motor is always switched off when
STO is active. The OFF1, OFF2 and
OFF3 signals have no effect.
Operation
6.3 Safe Torque Off (STO)
Safety Integrated - SINAMICS G110M, G120, G120C, G120D and SIMATIC ET 200pro FC-2
Function Manual, 01/2017, FW V4.7 SP6, A5E34261271B AD
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