Lenze EVS9332xP - Manual (Page 58)

Function library
Positioning control
3.4.3 Positioning modes (C1210)
3−30
l
EDSVS9332P−EXT DE 2.0
3.4.3 Positioning modes (C1210)
You can select the following positioning modes under C1210:
l Relative positioning (
¶ 3−30)
l Absolute positioning (
¶ 3−32)
l Absolute positioning with saving (
¶ 3−33)
3.4.3.1 Relative positioning
Purpose
l Use with infinite applications, e.g. a cutter.
Function
l Set positioning mode (C1210) = 1.
l Absolute target positions cannot be approached. A fault is indicated (P07).
l The setpoint positions and actual positions are reset prior to a new positioning.
– The current following error is maintained (POS−SETPOS = 0, POS−ACTPOS = current
following error).
l The position limit values (C1223, C1224) determine the maximum feed length in the
corresponding direction.
Tip!
If you do not need the travel range limit switch remove the connection to the digital input terminals
(DIGIN) or switch to +24 V.
l Homing is not necessary, but can be used to set the machine to a defined position.
Rounding error
Without special measures for the mechanical design the path covered of a defined target position
may amount to a fractional number of increments (e. g. 1554.4 inc.). The internal calculation merely
considers the integer part of this value (= 1554 inc.).
For a relative positioning, the momentary target position of which always refers to the previous target
position, rounding errors are propagated with each distance traversed.
This effect can lead to a drifting of the holding position of a conveyor. Therefore it must be observed
that all required target positions can be displayed without decimal position of an increment (see
position resolution).