Setting Set Reference Point; Displacement Of The Working Range On The Axis By Set Reference Point - Siemens SIMATIC FM 351 Installation Manual

Operating Modes and Settings
9.7
Definition
Requirements
Effects of the
Setting
Table 9-7
9
All numerical values are given in the units of mm.
Special Remarks
for Absolute
Encoders
9-16

Setting Set Reference Point

With the setting Set reference point you synchronize the axis.
Take note of the following requirements for this setting:
The channel must be parameterized.
Linear axis: The reference-point coordinate must not be located outside
the software limit switches.
For a rotary axis: The reference-point coordinate must be greater than or
equal to zero and less than the value End of rotary axis.
Using an example of Set reference point to 400 mm, you can see how this
setting projects the traverse range to a certain physical position on the axis. It
has the following effects:
The actual position is set to the value of the reference-point coordinate.
The working range is physically displaced on the axis.
The individual points retain their original value, but are now located at
new physical positions.

Displacement of the Working Range on the Axis by Set reference point

Set reference point
SLS REF
–500
0
–500
With absolute encoders this setting is used to assign a coordinate system to
the encoder range.
The FM 351 then determines an absolute encoder adjustment (see Chapter
8.4) which is assigned to the value of the reference-point coordinate. With
this the absolute encoder is matched to the axis.
ACT SLE
[mm]
500
0
200
Projection of
the working the working
range by Set ref-
erence point to
400 mm
400
SLS REF ACT SLE
-400 -200 200 400
-400 -200 400 400
FM 351 Positioning Function Module
EWA 4NEB 720 6001-02