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MG.10.J8.02 – VLT is a registered Danfoss trade mark
Programmable SyncPos motion controller
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Example: Slave Synchronization with Marker
In the following example, the conveyor belt is the
slave and the stamp roller the master, since the
take-up and delivery of the dye must be conti-
nuous for a uniform printing process. A maximum
of 20 cardboard boxes are transported on the con-
veyor belt per minute. The distance of the boxes is
not larger than one master cycle length. Stamp roller
and box must run in sync during the printing
operation:
In contrast to the synchronization with master
marker correction, here the slave position is being
corrected instead of the curve.
How to edit a curve for the Slave Synchronization
1.
Set the VLT with the required parameters and
save these user parameters with
"PARAMETERS"
→
"SAVE TO FILE" with the
extension „cnf“.
2.
Start the
→
"CAM-EDITOR" and load this cnf
file with "FILE"
→
"LOAD CNF".
3.
Determine the gearing factor of the master in
M U units.
Gearing factor = 5/1
Encoder resolution (Increm. encoder) = 500
One revolution of the roller is 360 degrees. We
are going to work with a resolution of
1/10 degrees. Therefore we are dividing one
revolution of the roller into 3600 work units:
Scaling factor = 3600
Enter these whole number values in the index
card
→
"SYNCHRONIZATION":
Syncfactor Master [49] = 25
Syncfactor Slave [50] = 9
4.
Enter the gearing factor of the slave in user
untis [UU]:
The input should be possible in 1/10 mm
resolution.
The drive is connected with the conveyor belt
by means of a gearing of 25:11; i.e. the motor
makes 25, the drive pulley 11 revolutions.
Gearing factor = 25/11
Incremental encoder directly on the master
drive; encoder resolution = 4096
The drive pulley has 20 teeth/revolution,
2 teeth correspond to 10 mm, thus 1 revolution
corresponds to = 100 mm conveyor belt feed
or 1000/10 mm.
Thus, the scaling factor is 1000
Enter these values in the index card
→
"ENCODE R":
User factor numerator [23] = 2048
User factor denominator [26] = 55
5.
Determine a whole number factor for the inter-
vals in the index card
→
"CURVE DATA" so
that the fixpoints are on the interpolation
points.
A complete cycle length of the master is
360 degrees; this corresponds to 3600 MU.
The
→
"NUMBER OF INTERVALS" = 36 pro-
duces a reasonable interval time of 27.7ms.
6.
Define
→
"FIX POINTS" for the roller (slave)
and the conveyor belt (master) and the point
type „1“ for curve points. The function
→
"SNAP ON GRID" should be activated.
Points
Master
Slave
Type
1
0
0
1
2
1200
1500
1
3
2400
2500
1
4
3600
4000
1
7.
Master and slave must run synchronously with
the same velocity between the master position
1200 to 2400. For this, you need to have a
straight line which is determined with two tan-
gent points. Thus, for these two fixpoints you
must define the
→
"TYPE" = 2 for tangent point
and insert two fixpoints so that the curve can be
calculated.
CAM Control