Restoration Of Position After Power Off - Siemens SINUMERIK 828D Function Manual

R1: Reference point approach
15.5 Referencing with incremental measurement systems
Figure 15-11 Reference point distance plus reference point offset smaller than braking distance
15.5.6

Restoration of position after POWER OFF

General information
In the case of incremental encoders, actual values can be buffered even after POWER OFF. This gives rise to
the following functionalities:
• "Buffered actual value" followed by automatic referencing.
• "Position restoration with POWER ON":
The buffered actual values are adopted as automatic reference values.
During the time in which the measuring system (encoder) of the machine axis is switched off
(POWER OFF, "parking" the axis, etc.), the machine axis may not be moved any further by
mechanical means (e.g. "coasting" axes). This must be supported by the machine
manufacturer with such measures as holding brakes, etc., and ensured by the user.
Otherwise the actual value system of the machine axis will no longer be synchronized
resulting in danger to personnel and machine. If this situation cannot be prevented
mechanically, it would be better to use absolute encoders.
1218
WARNING
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
Basic Functions