Siemens SIMATIC FM 453, Manual

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9-57
FM 453 Servo Drive / Step Drive Positioning Module
C79000-G7076-C453-01
9.5 Axis Type
You can select the axis type with machine data item MD8. Choose either of
the following types:
S
Linear axis
S
Rotary axis
A linear axis moves between two range limits (traversing range min –10
9
,
max 10
9
). The range limits may be bounded by software limit switches
(MD21, MD22) to form the “working range.”
Linear axes have a limited traversing range. The limits are imposed by the:
S
Resolution of the numerical scale
S
The range covered by an absolute encoder.
M
Movement
Encoder
G
Motor
Fig. 9-3 Linear Axis
With rotary axes, the actual value is reset to “0” after one revolution. Rotary
axes thus have an infinite traversing range.
0
5 000
9 999
Fig. 9-4 Rotary Axis
Before you start a movement in “MDI” and “Automatic” modes, you can
define a fixed direction of rotation with R+ or R–.
Overview
Linear Axis
Rotary Axis
Description of Functions