Siemens SINUMERIK 828D Function Manual page 1221

The "Position restored" state can only be exited by referencing the axis. As a consequence, IS
DB31, .... DBX71.4/5 ("restored 1/2") is deleted and IS DB31, .... DBX60.4/5 ("referenced/synchronized 1/2") is
set.
Note
In the case of spindles, the states "Position restored" and "Referenced/Synchronized" can
also be deleted by exceeding the encoder limit frequency.
Retracting the tool in JOG mode
Once the tool has been retracted in JOG mode, axes whose positions have been restored are referenced. For
further details, see also machine data:
• MD20700 $MC_REFP_NC_START_LOCK (NC start lock without a home position).
• MD34110 $MA_REFP_CYCLE_NR (Axis sequence for channel-specific referencing)
The PLC prompts the display of this state with the output of a corresponding PLC message by evaluating the
above NC/PLC interface signals.
Note
If machine data MD20700 $MC_REFP_NC_START_LOCK is set to a value of "2", then an
NC start is also possible with "restored" axis positions (in the MDI mode or when
overstoring).
Basic Functions
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
15.5 Referencing with incremental measurement systems
R1: Reference point approach
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