Siemens SIMATIC S7-300 Manual page 149

Set the referencing velocity to the highest value compatible with your re-
quirements. It is important to be able to decelerate to the reducing velocity
across the length of the reference-point switch. If this is not the case, an addi-
tional repositioning to the RPS occurs before the search phase of the synchro-
nizing zero pulse begins. Compare the cycle of the executed traversing move-
ments with Section 9.2.3 and optimize the referencing speed (MD28).
Then readjust the reference-point coordinates proper by entering the neces-
sary reference-point shift in the machine data. After the machine data is acti-
vated, the new reference-point shift takes effect with the next search for ref-
erence.
Axis with absolute In a suitable mode ("jogging", "incremental relative") move to a known point
encoder (SSI) on the axis and execute the Set reference point function with the known posi-
tion value. The set position and actual position will immediately be set to this
value, and the allocation of an absolute value to the absolute encoder (SSI)
will be entered in the machine data record (MD17). If you want to archive
this value externally, apart from the module's own data memory, perform a
readout of the machine data DB and save it to a floppy disk or to the hard
disk of your PG.
7.3.6 Activating position controller diagnostics
Overview
Once the position controller has been optimized, activate the position con-
troller diagnostics. If position control is performing improperly or the axis is
responding abnormally, this function will trigger error messages.
You can use the following flow chart to start the position controller diagnos-
tics:
FM 354 Servo Drive Positioning Module
Starting up the FM 354
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