Determining A Reference Point With Limit Switches - Siemens SIMATIC S5 Manual

IP 267
Then you assign a "Start forwards" job setting a start/stop rate. Pulse output
immediately stops when the reference switch is detected. The position reached is
the reference point for further positioning jobs.
PD I -
Figure 5-4. Reference Point Calculation with the REF Switch
5.4.2

Determining a Reference Point with Limit Switches

If you select limit switch I+, for example, as the reference switch, start a
positioning job with high velocity, "Start forwards" and maximum path. The
traversing movement is ended with the deceleration ramp at the limit switch.
The limit switch is then left at low velocity with the "Start backwards" job.
PD I -
Figure 5-5. Determining a Reference Point with the I+ Switch
EWA 4NEB 812 6061-02a
Start forwards
f
ss
Starting
REF
point
Start backwards
Start forwards
f
ss
Starting
point
Notes on Operation
I+ PD
f
ss
I+ PD
Start backwards
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