Siemens SINUMERIK 840D sl Function Manual page 44

A2: Various NC/PLC interface signals and functions
2.2 NC/PLC interface signals - only 840D sl
not exceeded during follow-up mode. If the encoder limit frequency is exceeded, the controller
will detect this:
● DB31, ... DBX60.4 / 60.5 = 0 (referenced/synchronized 1 / 2)
● Alarm: "21610 Encoder frequency exceeded"
Note
If "follow-up mode" is deactivated for a machine axis, which is part of an active
transformation (e.g. TRANSMIT), this can generate motions as part of repositioning
(REPOS) other machine axes involved in the transformation.
Monitoring
If a machine axis is in follow-up mode, the following monitoring mechanisms will not act:
● Standstill monitoring
● Clamping monitoring
● Positioning monitoring
Effects on other interface signals:
● DB31, ... DBX60.7 = 0 (position reached with exact stop fine)
● DB31, ... DBX60.6 = 0 (position reached with exact stop coarse)
DB31, ... DBX1.5/1.6 (position measuring system 1/2)
Two measuring systems can be connected to one machine axis, e.g.
● Indirect motor measuring system
● Direct measuring system on load
Only one measuring system can be active at any one time. All closed-loop control, positioning
operations, etc. involving the machine axis always relate to the active measuring system.
Figure 2-4 Position measuring systems 1 and 2
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Function Manual, 01/2015, 6FC5397-0BP40-5BA2
Basic Functions