Siemens SIMATIC FM 351 Manual page 15

Encoders
The encoder supplies information both about position and direction. The following
encoders can be connected:
Incremental encoders with 5 V differential signals, symmetrical
Incremental encoders with 24 V signals, asymmetrical
SSI absolute encoders
FM 351 Positioning Module
The FM 351 can position up to two axes automatically using rapid/creep feed.
The power unit is controlled via four digital outputs (see Section 8.3, page 8-6).
The FM 351 positioning module calculates the current actual position value of the
axis from the encoder signals that are proportional to the distance moved (see
Section 8.5, page 8-15 and Section 8.7, page 8-22).
The FM 351 provides the following modes and functions:
"Jogging" (see Section 9.2, page 9-8).
"Reference point approach" (see Section 9.3, page 9-11).
"Absolute/relative incremental approach" (see Section 9.4, page 9-17).
Set actual value (see Section 9.5, page 9-23).
Set reference point (see Section 9.6, page 9-25).
Loop traverse (see Section 9.7, page 9-27).
CPU
The CPU executes the user program. Data and signals are exchanged between
the user program and the module using function calls.
PC/PG
The PC/programming device is used for the following:
Parameter assignment: You make the parameter settings for the FM 351 either
with the parameter dialogs or using the parameter DB (see Section 6.5.4, page
6-14).
Programming: You program the FM 351 with functions that you incorporate
directly in your user program.
Testing and commissioning: You test the FM 351 and commission it using the
parameter dialogs .
FM 351 Positioning Module
C79000-G7076-C351-02
Product Overview
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