Axis, Drive And Encoder - Siemens simatic et 200s Operating Instructions Manual

6.6.2

Axis, Drive and Encoder

Evaluation of the Encoder Signals
The 1PosSSI/Analog evaluates the encoder value supplied by the SSI encoder directly in
increments and forms the actual value in increments (actual value = encoder value).
The actual value lies in the encoder range from
0 to (number of rotations * number of increments) -1.
The 1PosSSI/Analog generates an overrun or underrun of the actual value at the limits of the
operating range. You specify the encoder range with the parameters for the number of
rotations and number of increments. The maximum encoder range is 4096x4096 increments.
Reversal of the direction of rotation
You can use the parameter for the reversal of the direction of rotation to adapt the direction
of rotation of the encoder to that of the drive and the axis.
Controlling the Drive
You assign parameters how the drive is to be controlled using the Function DO parameter.
If you select Output, the following applies: The control is bipolar. The drive is controlled using
the analog output QV+/M
You can read the status of the OUT digital output from the feedback interface, with a delay
that corresponds to the updating rate.
Figure 6-7
ET 200S Positioning
Operating Instructions, 05/2007, A5E00124871-04
±10 V to +10 V. You can use the digital output OUT as you wish.
ana
Schematic Diagram of the Bipolar Control of a Drive
1PosSSI/Analog
6.6 Functions of the 1PosSSI/Analog
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