Siemens simatic et 200s Operating Instructions Manual page 321

Dosing operation:
If incremental encoders are used, the 1PosU can be used for dosing. Dosing operation is set
once in the parameters. In dosing operation the 1PosU only evaluates the encoder signal A
(/A). The actual value is incremented at each rising edge.
In dosing operation only the functions inching and relative positioning are available for
controlling the digital outputs.
The dosing function itself is triggered by means of the relative positioning function. The
dosing quantity is specified during starting by means of the control signals (distance).
At every start the actual value is set to 0 and the digital outputs are controlled as a function
of the switchover and switch-off difference.
Figure 7-4
Interfaces to the Control Program and the Axis
To execute the function, the 1PosU has digital inputs as an interface to the axis, encoder
signals for the connection to an encoder and digital outputs to control the drive.
You can modify and monitor the types of motion (MODES) and functions (JOBs) with your
control program using control signals and feedback signals.
See also
Parameter List (Page 368)
ET 200S Positioning
Operating Instructions, 05/2007, A5E00124871-04
How the 1PosU Works
1PosUniversal/Digital
7.6 Functions of the 1PosU
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