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Synchronizing controller
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MG.10.N4.02 - VLT is a registered Danfoss trademark
Then use the following procedure:
1. Close the contacts at terminal 32 (clockwise/forward direction) or terminal 33 (counter-
clockwise/reverse). During the test the last value of the first display line will indicate the
track error (PID error). After the test run is completed you can see the maximum track
error (PID error) in the display.
2. Increase the P-portion (par. 702). After each change you should make a test run to find
the right setting. If the drive becomes unsteady or if a message is given about over-
voltage or over-current, then reduce the value in parameter 702 to about 70-80% of the
set value.
3. Now set the D-portion (parameter 703) to 5 times the value of parameter 702.
4. If a lower synchronizing error is required the I-portion (parameter 704) can be set to a
low value e.g. 10 but be careful a too high value will course overshoot and instability.
For test run with virtual master the following parameters must be set:
Parameter 748 Virtual master reference: Select the reference source for setting the velocity
of the virtual master. “0” is analogue input 53, “1” is analogue input 60, “2”
is parameter 216 and “3” is Field bus PCD 2.
Parameter 749 Virtual master acceleration: Set the acceleration of the virtual master in
encoder pulses per second
2
.
Parameter 750 Virtual master maximum speed: Set the maximum velocity of the virtual
master in encoder pulses per second.
Then use the following procedure:
1. Disconnect the master encoder from the synchronizing controller (MK3B). Start test run
with virtual master by activating input 3. During test run you can read the track error in
the last value of the first display line. At stop the maximum track error during the test run
is read out. Because velocity synchronization is selected (parameter 728 = 0) the track
error is velocity deviance between master and slave.
2. If more accurate and dynamic control is required the P-portion (parameter 702) must be
increased. If the slave becomes unstable the value must be reduced to by approximately
25%.
3. Now set the D-portion (parameter 703) to 5 times the value of parameter 702
4. If a lower synchronizing error is required the I-portion (parameter 704) can be set to a
low value e.g. 10 but be careful a too high value will course overshoot and instability.
To store the optimized values
Activate Input I4 (Store) or change the value of parameter 710 to “1”