0x15
Maximum Travel In
Positive Direction
(Phys. Unit)
Soft limit in positive direction, in relation to the
zero position.
The positive travel range limit cannot be used
for reference moves if this value is smaller than
the position value for the positive travel range
limit (that results from the sum of parameters
0x16 and 0x2F).
The value can be negative.
0x30
Maximum Travel In
Negative Direction
(Phys. Unit)
Soft limit in a negative direction, in relation to
the zero position.
The negative travel range limit cannot be used
for reference moves if this value is greater than
the position value for the negative travel range
limit (that results from the difference between
parameters 0x16 and 0x17).
The value can be negative.
4.9.12 Reference Point Definition
Whether a reference point definition is necessary for the axis depends on the signal type of
the position sensor:
■
Absolute measuring position sensor: Reference point definition is not necessary.
■
Incremental position sensor: Reference point definition is necessary.
Incremental sensors only supply relative motion information. When the positioner is
equipped with an incremental position sensor, the controller therefore does not know the
absolute position of the axis during switch-on or reboot. So that absolute target positions
can be commanded and reached, a reference point definition must be performed
beforehand.
Reference point definition options
The reference point definition can be performed in different ways:
■
Reference move (default): A reference move moves the axis to a specifically defined
point, e.g., to the reference point switch, to a limit switch or to a hard stop. At this point,
the current position is set to a defined value. The controller now knows the absolute axis
position. The reference move is started with the
■
Setting the absolute position manually: If this type of reference point definition was
enabled with the
command, you can set the current position of the axis to an
arbitrary value at an arbitrary point using the
command. Here the axis is not moved.
The controller knows the absolute axis position afterwards.
can be used to query whether an axis is referenced.
reference point definition mode for an axis.
The Use Hard Stops For Referencing? parameter (0x7A) sets whether hard stops may be
used for reference moves. The set parameter value can be queried with the
command.
During startup using PIMikroMove, the reference point definition is performed via a
reference move by default. Knowledge of the commands and parameters described here is
not needed for reference point definition using PIMikroMove.
Reference move procedure
To achieve maximum repeatability of the reference point definition, every reference move
comprises the following steps:
1. First move to the selected switch.
The default direction for reference moves is determined by the Reference Travel Direction
parameter (0x47).
4 PRODUCT DESCRIPTION
PZ285EN
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