Siemens SINUMERIK 840D sl Function Manual page 1571

• The measuring system has already been successfully referenced with reference point
Encoder status =
2:
• The machine axis was disabled in "Exact stop fine" status.
Note
Within the scope of actual value buffering, the following axis specific interface signal is
evaluated:
DB31, ... DBX60.7 (Position reached with fine exact stop)
The actual values of machine axes that do not use the signal cannot be buffered.
Functional sequence
Two different cases apply for automatic referencing, which depend on the encoder status:
• Case 1: Encoder status = 2
• Case 2: Encoder status = 1
Basic logic functions: Reference Point Approach (R1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
approach.
This is identified by the NC by changing the encoder status from 1 to 2.
Encoder is referenced, an exact stop is reached, and automatic
referencing is active the next time the encoder is activated.
Automatic referencing in parameterized, the measuring system has been referenced and
the machine axis was switched off in status "exact stop fine".
As a result:
– The actual value system of the machine axis is synchronized with the buffered actual
value.
– The status of the machine axis is set to "Referenced".
DB31, ... DBX60.4 / 60.5 (Referenced/Synchronized 1/2) = 1
Automatic referencing in parameterized but the measuring system has either not yet been
referenced or the machine axis was not switched off in status "exact stop fine".
As a result:
– The actual value system of the machine axis is synchronized with zero.
– The status of the machine axis is set to "Not referenced":
DB31, ... DBX60.4 / 60.5 (Referenced/Synchronized 1/2) = 0
2.4 Referencing with incremental measurement systems
Detailed description
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