17-76 Position Axis Mode
Option:
Function:
[0]
*
Linear
Axis
The motion is within a position range defined
by
parameter 3-06 Minimum Position
and
parameter 3-07 Maximum Position
.
[1]
Rotary 0 -
Max
Continuous motion, where the position changes
between 0 and
. When passing the maximum position,
the reading restarts from 0.
[2]
Rotary
Min -
Max
NOTICE
This option is available only with
software version 48.20 and newer.
Continuous motion, where the position changes
between
parameter 3-06 Minimum Position
and
parameter 3-07 Maximum Position
. When passing
the maximum position, the reading restarts from
the minimum position.
17-77 Position Feedback Mode
Option:
Function:
NOTICE
This parameter is only available with
software version 48.2X and newer.
Select the mode for handling absolute encoders.
Select
[0] Relative
if the application requires to
track the position when the position value
exceeds the measuring range of the encoder, for
example when using single turn encoders for
linear motion. Select
[1] Absolute
if the position
values are always within the measuring range of
the encoder, for example when using a laser
distance measuring device.
[0]
*
Relative
The actual position is set to the absolute position
read from the encoder at power-up, and then the
frequency converter uses only the position
changes for calculating the actual position. In this
mode, the actual position values are between
-2147483648 and 2147483647 even when the
values exceed the measuring range of the
encoder. To save and use the absolute position
values outside the measuring range of the
encoder after power down, set
parameter 17-75 Position Recovery at Power-up
to
[1] On
. The position value is accurate if the
encoder does not move by more than half of the
encoder measuring range when the frequency
converter is powered down.
[1] Absolute The frequency converter uses the absolute
position from the encoder as actual position
continuously. In this mode, the actual position
values are between 0 and the maximum position
of the encoder. The maximum position is
17-77 Position Feedback Mode
Option:
Function:
determined by the number of bits, for example,
the SSI encoder has 25 bits and its maximum
value is 2
25
= 33554432. Set
parameter 3-07 Maximum Position
to the maximum
value of the encoder scaled according to
parameter 7-94 Position PI Feedback Scale
Numerator
,
parameter 7-95 Position PI Feebback
,
, and
. If the position exceeds the
measuring range of the encoder, the absolute
position reference is lost.
For example, use this option if there is a laser
distance-measuring device and there is a risk that
some external objects may occasionally interfere
with the laser beam. In this case, the absolute
positioning will work correctly when the external
disturbance disappears.
17-78 Active Position Counter
Option:
Function:
The drive has 4 individual position counters.
Only the selected counter is updated. Allows
tracking position of up to 4 motors controlled
by one drive, one motor at a time. The active
counter can be selected by this parameter in
the same set-up or by set-up change when
selecting between motors.
[0]
*
Counter 0
[1]
Counter 1
[2]
Counter 2
[3]
Counter 3
3.17.6 17-8* Position Homing
Parameters for configuring the homing function. The
homing function creates a position reference in the
physical machine.
17-80 Homing Function
Option:
Function:
NOTICE
This parameter is only available with
software version 48.XX.
Select the homing function. The homing
function creates a position reference in the
physical machine. The selected homing function
can be activated with a digital input or a
fieldbus bit. Homing is not required when using
absolute encoders. All homing functions except
[2] Home Sync Function
require a start homing
signal.
Parameter Descriptions
VLT
®
AutomationDrive FC 301/302
220
Danfoss A/S © 10/2018 All rights reserved.
MG33MP02
3
3
Summary of Contents for VLT AutomationDrive FC 302
Page 2: ......