Siemens Sinamics S120 Function Manual page 159

3. Set the position tolerance back to the normal value using bit 3 (= 0) in byte 3 of S_STW2.
4. The actual values are then synchronized once automatically. This synchronization is used
to compensate any possible difference that occurs between the position actual values of
the two monitoring channels as a result of the switchover operation.
The new gearbox stage is then active.
Image 4-21 Gearbox switchover with increased position tolerance
Diagnostics
The selected gearbox stage is displayed for diagnostic purposes in parameter r9720, bits 24
to 26.
The selected gearbox stage is displayed for diagnostic purposes in parameter r9720, bit 27.
Safety Integrated
Function Manual, (FHS), 07/2016, 6SL3097-4AR00-0BP6
Description of Safety Integrated functions
4.2 Safety Integrated Extended Functions
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