If The Sensor Distance Is Larger Than One Master Cycle Length - Danfoss VLT5000 SyncPos Operating Instructions Manual

14. Verify whether the velocity and acceleration of
the slave remain within the limit. For this pur-
pose, you must activate the illustration of the
→ "VELOCITY" and of the →
and then the illustration of the
→
"ACCELERATION" and of the
→
"ACC.-LIMIT".
15. "FILE" → "SAVE as CNF"
How to load the curve into the VLT
You can load the cnf file with the modified para-
meters and the – automatically generated – curve
arrays into the VLT by means of "PARAMETERS"
→ "RESTORE FROM FILE".
How to integrate the curve "marker
synchronization" into the control program
Since the curve is stored internally as an array, the
DIM instruction must appear first in your program:
DIM marker[112] // See number of elements in
// the title bar of CAM-Editor
HO M E
// Slave axis performs a home run (switch for
// zero position on top); afterwards, the slave
// will be in the zero position (0 degrees)
// (Omitted if an absolute encoder is used)
SETCURVE marker
// Set stamp curve with marker
dist = GET SYNCMPULSM
DEFMCPOS (1000-dist)
// This is the location that corresponds
// to the sensor signal
SET SYNCMSTART 2000
// Counting of the master pulse does not begin
// until the next edge comes from the sensor
SYNCCMM 0
// Synchronize in CAM-Mode until motor stop
SYNCCSTART 1
// Engage roller with start point pair 1
// Synchronous operation
WAITI 4 ON
// Wait for input signal when conveyor belt
// is being switched off
SYNCCSTOP 2 0
// Disengage roller with stop point pair 1
// and stop at position 0 degrees
MG.10.J8.02 – VLT is a registered Danfoss trade mark
■ If the sensor distance is larger than one master
"VEL.-LIMIT"
// Distance to sensor
Programmable SyncPos motion controller
cycle length
In many applications, the marker cannot be placed
within one master cycle length, for example in the
case of the following equipment for the production
of plastic bags:
Since no markers can be installed between the
slaves here, there is only a marker reader in this
application; the welding station is much farther
away than one master cycle length. Since the
distance of the sensor is larger than one master
cycle length, a buffer is provided for the marker
deviation. When the marker appears, the value is
entered in the buffer and read out upon the
appearance of the next marker:
In order to assess in what area corrections may be
made, you should subtract the master cycle length
as often as necessary until the value is < 1 master
cycle length. This is the maximum permitted
distance for making corrections. In this example, it
is 6375 – 4000 = 2375 and thus the same correc-
tion range as in the previous example.
Stamping roller = Slave
Conveyor belt = Master
Master positions (1/100 mm)
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