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MG.10.J8.02 – VLT is a registered Danfoss trade mark
Programmable SyncPos motion controller
22
VELRES
The
V
V
V
V
Velocit
elocit
elocit
elocit
elocit y resolution
y resolution
y resolution
y resolution
y resolution
VELRES defines a relative
size for the velocity values of the motion com-
mands and parameters.
The information concerning speed and accelera-
tion can then be made in whole numbers in rela-
tion to this scaling. The value 100 means that the
information in the commands are related to 100,
thus in percent.
Content
Velocity resolution
Parameter Group
Axis parameter velocity AXV
CAM-Editor: index card velocity
Value range
1 … MLONG
★
100
23
POSFACT_Z
All path information in motion commands are made
in user units and are converted to quad-counts
internally. By choosing these scaling units
correspondingly it is possible to work with any tech-
nical measurement unit (for example mm).
This factor is a fraction which consists of a nume-
rator and denominator.
POSFACT_Z / POSFACT_N = 1 UU
Scaling determines how many quad-counts make
up a user unit. For example, if it is 50375/1000,
then one UU corresponds to exactly 50.375 qc.
In CAM-Mode, the parameter is used to fix the unit
for the slave drive so that it is possible to work with
meaningful units in the CAM-Editor. See sample 2.
provided that:
Encoder =
Incremental encoder (in the
case of absolute encoders, the
multiplier 4 is omitted)
Scaling factor =
Number of user units UU (qc)
that correspond to one revolu-
tion 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.
Content
Numerator user factor
or in CAM mode conversion of the units qc into UU
Parameter Group
Axis parameter Encoder AXE
CAM-Editor: index card Encoder
Value range
1 … MLONG/max. position (UU)
★
1000
The limit depends on the maximum target position
max. position (UU) * POSFACT_Z < MLONG
where by
Example: POSA max. position (UU)
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 if we want to work with 1/10 mm
resolution = 5 * 10 = 50
Numerator user factor [23]
= 1000
Denominator user factor [26] = 1
Example 2: Cylinder
Gear factor = 5/1
Encoder resolution (incremental encoder) = 500
One revolution of the cylinder is 360 degrees. We
want to work with a resolution of 1/10 degrees. This
means that we divide one revolution of the cylinder
into 3600 units.
Scaling factor = 3600
Numerator user factor [23]
= 25
Denominator user factor [26] = 9
Parameter Reference