Siemens SINUMERIK MC Commissioning Manual page 201

Figure 4-33 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.
"Safe gearbox switchover" and referencing
The gearbox stage switchover means that the reference position and the user agreement are
lost. This means that after a gearbox switchover, initial referencing is required, in order to return
to the "safely referenced" state (see Chapter Safe referencing (Page 189)).
Safety Integrated (with SINAMICS S120)
Commissioning Manual, 02/2020, A5E46305916B AB
Safety functions integrated in the drive
4.20 Safe gearbox stage switchover
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