Festo SEC-AC-305-CO, Manual

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7. Operating modes/Adjustment of the Operating Mode
7−7
Festo P.BE−SEC−AC−CO−E N en 0802a
7.2 Operating Mode "Homing mode"
7.2.1 Survey
This chapter describes how the servo controller searches the
start position (also called reference point or zero point).
There are various methods to determine this position. Either
the limit switches at the end of the positioning range can be
used or a reference switch (zero point switch) within the poss
ible range of motion. Among some methods the zero impulse
of the used encoder (resolver, incremental encoder, etc.) can
be included to achieve a state that can be reproduced as well
as possible.
Fig.7/1: Homing operation
The user can determine the velocity, acceleration, and the
kind of homing operation. After the servo controller has found
its reference the zero position can be moved to the desired
point via the object
home_offset .
There are two kinds of speed for the homing operation. The
higher search speed (
speed_during_search_for_switch ) is
used to find the limit switch respectively the reference switch.
To determine the reference slope exactly a lower speed is
used (
speed_during_search_for_zero ) .