Danfoss VLT AutomationDrive FC 301 Programming Manual page 183

Parameter Descriptions
17-70 Position Unit
Select the physical unit for showing the position values on the
LCP.
Option: Function:
[2] mm Millimeters.
[3] inc Increments.
[4] ° Degrees.
[5] rad Radians.
[6] % Percent.
[7] qc Quad count, which is ¼ of an encoder pulse when
using quadrature encoder signal.
17-71 Position Unit Scale
Array [2]
Enter the scaling factor for the position values. The scaling
function multiplies the readout values by 10
value of this parameter. For example, if x=2, the value 5 is shown
as 500.
The elements of the array are:
•
Index 0 is the scaling factor for readout and settings of
position values in parameters or in a fieldbus. Index 1
contains exceptions.
•
Index 1 is the scaling factor for readout of position error
(parameter 16-08 Position Error) and for the value of
parameter 3-08 On Target Window.
Range:
0 [-3 - 3]
*
17-72 Position Unit Numerator
This parameter is the numerator in the equation which defines
the relation between one encoder revolution and physical
movement of machine.
Par . 17 − 72
Position unit = × Encoder revolutions
Par . 17 − 73
Example:
Consider a turn table application. The encoder makes 10
revolutions when the table makes 1 revolution. The position unit
is a degree. For this set-up, enter the following values:
•
Parameter 17-72 Position Unit Numerator=360
•
Parameter 17-73 Position Unit Denominator=10
Set the physical unit for position values in
parameter 17-70 Position Unit.
Range:
1024 [-2000000000 -
*
2000000000]
17-73 Position Unit Denominator
See parameter 17-72 Position Unit Numerator.
Range:
1 [-2000000000 - 2000000000]
*
MG33ML02
Programming Guide
17-74 Position Offset
Enter the absolute encoder position offset. Use this parameter to
adjust the zero position of the encoder without physically
moving the encoder.
Set the physical unit for position values in
parameter 17-70 Position Unit.
Range:
0 CustomRea-
doutUnit2
17-75 Position Recovery at Power-up
Select the actual position after power-up when using open loop
or incremental encoders.
Option: Function:
[0]
[1]
x
, where x is the
17-76 Position Axis Mode
Select the axis type for position counting.
Option:
[0]
[1]
Function:
3.18.6 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
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.
Function:
Option:
[0]
[1]
Function:
Danfoss A/S © 02/2016 All rights reserved.
[-2000000000 -
2000000000
*
CustomReadoutUnit2]
Off The actual position is 0 after power-up.
*
On The frequency converter stores the actual position at
power down and uses it as the actual position when
powered up.
Function:
Linear Axis The motion is within a position range defined
*
by parameter 3-06 Minimum Position and
parameter 3-07 Maximum Position.
Rotary Axis Continuous motion, where the position
changes between 0 and
parameter 3-07 Maximum Position. When
passing the maximum position, the reading
restarts from 0.
Function:
No Homing No homing function. The actual position is 0
*
after power-up, independent of the physical
machine position.
Home Actual position is set to the value of
Position parameter 17-82 Home Position, index 0.
3 3
Function:
181