Siemens SIMATIC S7-200 System Manual page 320

S7-200 Programmable Controller System Manual
Selecting the Location of the Work Zone to Eliminate Backlash
Figure 9-25 shows the work zone in relationship to the reference point (RP), the RPS Active zone,
and the limit switches (LMT+ and LMT--) for an approach direction that eliminates the backlash.
The second part of the illustration places the work zone so that the backlash is not eliminated.
Figure 9-25 shows RP seek mode 3. A similar placement of the work zone is possible, although
not recommended, for each of the search sequences for each of the other RP seek modes.
Backlash is eliminated
RP Seek Direction: Negative
RP Approach Direction: Negative
Positive motion
Negative motion
Backlash is not eliminated
RP Seek Direction: Negative
RP Approach Direction: Negative
Positive motion
Negative motion
Figure 9-25 Placement of the Work Zone with and without the Elimination of Backlash
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LMT- -
Active
Work Zone
LMT- -
Active
RPS
Active
RP
RPS
Active
RP
Work Zone