Technical data

Safety Integrated Functions
8.5 Safety Integrated Extended Functions
Function Manual
Function Manual, 06/2012, 6SL3097-4AB10-0BP4
367
Examples:
1. For the hoisting gear of a crane, the suspended load can accelerate the motor as soon as
the motor is switched off. In this case, the safety functions "without encoder" are not
permitted.
Even if the mechanical brake of the hoisting gear is generally applied after the motor has
been switched off, the use of safety functions "without encoder" in this application is still
prohibited.
2. A horizontal conveyor is always braked to a standstill due to friction as soon as the motor
is switched off. In this case, the safety functions "without encoder" can be used without
any restriction.
8.5.2 Safe Torque Off
In addition to the control options specified under Safety Integrated Basic Functions, "Safe
Torque Off (STO) under Safety Integrated Extended Functions can also be activated via
PROFIsafe.
Functional features of "Safe Torque Off"
The functionality of "Safe Torque Off (STO)" is described in the section, "Safety Integrated
Basic Functions".
8.5.3 Safe Stop 1 (SS1)
8.5.3.1 Safe Stop 1 (SS1, time and acceleration controlled)
The SS1 function with an encoder monitors whether motor acceleration reaches
impermissible levels during the SS1 time.
The "Safe Stop 1" function can be used to stop the drive in accordance with EN 60204-1,
stop category 1. The drive brakes with the OFF3 ramp (p1135) once "Safe Stop 1" is
selected and switches to "Safe Torque Off" (STO) once the delay time has elapsed
(p9356/p9556) or when the shutdown speed is reached (p9360/p9560).
If the drive complies with acceleration monitoring limits, STO is triggered when the shutdown
speed is reached or after the SS1 time has expired. If acceleration monitoring limits are
violated, messages C01706 and C30706 are output and the drive is stopped with STOP A.