Siemens SIMATIC S5 Manual page 17

IP 266
The emergency limit switches, which are routed directly to the power section,
must also take the deceleration distance into account.
C A U T I O N :
If you initialize a linear axis unintentionally as a rotary axis, there are no soft-
ware limit switches. The drive can be stopped only over hardware limit
switches.
The rotary axis
A rotary axis is an axis with an unlimited positioning range.
This may be e. g.
• a rotary table or
• a continuous belt
When a rotary axis is used, the start and the end of the positioning range are
physically the same point on the axis.
The only effect the start of traversing range and end of traversing range
parameters have is that of switching the actual value displays.
Example
A traversing range of 0 mm to 400 mm
was specified in the machine data for a
continuous conveyor
0 mm and the value 400 mm both have
the same physical location on the belt.
When the value 400 mm is reached, the
display switches to 0 mm.
The hardware limit switches are evaluated in the same way as for a linear axis,
and provide extra protection when the positioning range is to be restricted to
values less than one revolution.
EWA 4NEB 812 6057-02
belt. The value
100
System Overview
200
0 = Start of traversing range
400 = End of traversing range
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