Siemens SIMATIC S7-300 Manual page 216

Description of Functions
Hint to the user:
You can use Retrigger Reference Point, for example, to compensate for slip-
page of the trolley in a high-bay warehouse during operation, without having
to resynchronize the axis with the Reference-Point Approach mode. When
retriggering in reference point approach with a zero pulse, be careful that the
total slippage between the reference point switch and the stepper motor does
not become so great that the synchronizing zero pulse migrates to an "adja-
cent" zero pulse!
Switch off enable With the "switch off enable input" function, you can switch off evaluation of
input the enable input (see Section 9.8.1).
Follow–up mode
The "follow–up mode" function is used to cancel closed–loop control of the
axis.
Deactivate end You can use this function to deactivate monitoring of the software limit
position
switches (see Section 9.9).
monitoring
It can be switched on or off only if "Processing in progress" = 0.
9-40
Start
–
Zero pulse
Reference-point switch input of the FM 354
For external movement of the axis, the actual value is tracked.
This setting can be switched on or off only if "Processing in progress" =0.
Target
RPS
Zero pulse for synchronization
FM 354 Servo Drive Positioning Module
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