Siemens SINAMICS S150 NEMA, Руководство по эксплуатации

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Functions, monitoring and protective functions
9.4 Extended functions
Enclosed Drives
Operating Instructions, 12/2018, A5E36652151A
665
Reference point approach of incremental measuring systems
The reference point approach (when using an incremental measuring system) is used to
move the drive to its reference point. The entire referencing cycle is controlled and monitored
by the drive.
Incremental measuring systems require the absolute dimensional reference to the machine’s
zero point to be established once a machine has been switched on. When switching on, the
position actual value x
0
in the non-referenced state is set to x
0
= 0. The reference point
approach can be used to move the drive to its reference point in a reproducible manner. The
geometry with a positive start direction (p2604 = "0") is shown below.
Figure 9-44 Example: Reference point approach with reference cam
The signal at binector input p2595 (start referencing) is used to trigger travel to the reference
cam (p2607 = 1) if a reference point approach is selected at the same time (0 signal at
binector input p2597 (select referencing type)). The signal in binector input p2595 (start
referencing) must be set during the entire referencing process otherwise the process is
aborted. Once started, the status signal r2684.11 (reference point set) is reset.
During the entire reference point approach, monitoring of the software limit switches is
inactive; only the maximum traversing range is checked. If necessary, monitoring of the
software limit switch is reactivated after completion.
The velocity override set is only effective during the search for the reference cam (step 1).
This ensures that the "cam end" and "zero mark" positions are always overrun at the same
speed. If signal propagation delays arise during switching processes, this ensures that the
offset caused during establishment of position is the same in each referencing process.
Axes that only have one zero mark over their entire traversing and/or modulo range are
identified using parameter p2607 = 0 (reference cam present). After starting the referencing
process, synchronization to the reference zero marks is started straight away (see step 2) for
these axes.