Danfoss MCO 305 Design Manual page 186

MCO 305 Design Guide
provided that: Gearing Factor
Encoder = Incremental encoder (in the case
of absolute encoders, the multi-
plier 4 is omitted)
Scaling factor = Number of user units UU (qc)
that correspond to one revolution
at the drive
In addition, it is possible to compress or expand
the curves with this factor without having to define
new curves each time. The use of numerator and
denominator for the gearing factor leads to a very
precise result since transmission ratios can be
represented as a fraction in virtually all cases.
Example 1
Shaft or spindle
25 motor revolutions result in 1 spindle revolution;
gearing factor = 25/1
Encoder resolution (incremental encoder) = 500
Spindle gradient = 1 revolution of the spindle =
5 mm
Scaling factor in case of working with 1/10 mm
resolution = 5 * 10 = 50
25
500 4
25 10
1
qc
50 1
Par. 32-12 User Unit Numerator
Par. 32-11 User Unit Denominator
Example 2
Cylinder:
Gear factor = 5/1
Encoder resolution (incremental encoder) = 500
One revolution of the cylinder is 360 degrees. It is
requested to work with a resolution of 1/10
degrees. This means that one revolution of the
cylinder is divided into 3600 units.
Scaling factor = 3600
5/1 500 4 5 500 4
qc
3600 3600
25 par. 32 - 12
qc 1 UU
9 par. 32 - 11
par. 32-12 User Unit Numerator
par. 32-11 User Unit Denominator
default setting
186
__ Parameter Reference __
Motor Revolution s
Revolution s on Output
4 1000
qc qc 1 UU
1
= 1000
= 1
qc 1 UU
User Unit Numerator
User Unit Denomintor
= 25
= 9
[ ] value for use in communication via serial communication port
®
MG.33.L4.02 – VLT is a registered Danfoss trademark
32-3* Encoder 1 - Master
Following parameters configures the interface for
the encoder 1:
32-30 Incremental Signal Type
MENCODERTYPE
Option
None
RS422 (TTL/line driver)
Function
Specifies type of the incremental encoder connec-
ted to Encoder 1 interface (X56).
Select None [0] if no incremental encoder is
connected.
Select RS422 (TTL/Line driver) [1] if a digital
incremental encoder with an interface according to
RS422 is connected.
32-31 Incremental Resolution
MENCODER
Range [Unit]
1 – MLONG [PPR]
Function
Set the resolution of the incremental encoder
connected to Encoder 1 interface (X56):
Digital incremental encoder (32-00 = [1]): The
resolution must be set in Pulses Per Revolution.
Encoder resolution can be found on encoder name-
plate or datasheet.
Note: Maximum frequency of the encoder signal
must not exceed 410 kHz.
Note: Parameter only visible when par. 32-30
[0]
[1]
1024
0