6
6.2
Positioning mode (P0700 = 3, from SW 2.1)
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SIMODRIVE 611 universal Description of Functions (FBU) – 04.05 Edition
6.2.6
Referencing with a distance–coded measuring system (from SW 8.3)
In the case of measurement systems with distancecoded reference
marks, it is not necessary to evaluate a reference cam or approach a
defined reference point in order to reference the machine axis.
Measurement systems of this type consist of a line grid and a reference
mark track running parallel to this. The distance between two
consecutive reference marks (zero marks) is defined differently, so that
the absolute position of the machine axis can be determined from the
distance.
For axes with incremental measuring systems, each time the system is
powered–up, the position reference to the machine zero point must be
established.
Synchronization is realized at reference point approach by accepting a
specific position value at a known point of the axis.
Note
The distance between the zero marks is continually monitored.
Only encoders are monitored, where the pulse number can be divided
by 16 or 10!
The reference point approach can be started in the ”positioning” mode
via the ”start referencing” input signal.
The input signal should be entered via the input terminal with function
number 65 and this must remain set up until the end of the reference
point approach is signaled using the output signal ”reference point set”
(function number 61).
If the ”start referencing” signal is reset during referencing, then refer-
encing is exited and the drive stops.
While referencing, at least two reference marks (zero marks) are
passed. The referencing is completed once these zero marks have
been passed and the axis has braked.
For a 2–axis control board, the reference point approach for both axes
can be started and executed, either one after the other or simulta-
neously.
The approach direction for reference point approach is defined using
P0166.
The reference point approach is executed in 2 phases (refer to the
table 6-34):
General
information
Starting the
reference point
approach
6 Description of the Functions
01.99
! not 611ue !
04.05