
Synchronizing controller
58
MG.10.N4.02 - VLT is a registered Danfoss trademark
Operation and operating functions
After all values have been set as described and the controller has been optimized for the application,
Parameter 729 Home function is set to the value of “2”. The drive can now be operated normally.
Home run
As parameter 729 is set to “2”, homing must be carried out before each start. To start homing the
contact at Terminal 19 is closed. The slave drive then travels to the home switch and stops there. If the
reversing procedure is set to “0”, the slave travels back to the start of the home switch; otherwise, the
offset arising from disabling reversing is added to the fixed offset.
Starting synchronization
Preferably, the master is first similarly brought into its start position and the slave activated by means
of I1 (SyncStart), then the master is started. This produces optimum synchronization. The slave can, of
course, also be started by, e.g. a start signal from the master, although in that case it should be noted
that the delay of the start signal can be prolonged by the scan time of e.g. the PLC. Attention should be
paid to the accuracy of the start signal. Hence, it is better to start the slave drive when the master is in
position. The position of the master, plus the value of the fixed offset, is the synchronization position to
which the slave drive will travel at the maximum permitted acceleration when started. It may happen
here that the slave drive travels faster than the master, as the slave drive needs to catch up with the
master position.
Stopping synchronization
On opening the SyncStart contact (I1), the slave is stopped at the permitted acceleration. Because
Home function is set at “2”, a new start is only possible after a renewed Home run.
Fine setting of the position
As soon as the slave drive is in position synchronization to the master, a displacement of this position
can be effected by means of Inputs 32 + 33. These settings are only temporary, i.e. the fine-setting
data are lost as soon as the converter is disconnected from the mains. If the displacement data are to
be retained, they must be stored by activating save Input (I4) or by means of Parameter 710 before
switching off.
Offset is related to the master position. Offset related to the slave position can be calculated as follows:
Offset_slave
=
739
738
*
Parameter
Parameter
Offset
Switching to another gear ratio
During synchronization, a new gear ratio can be selected at Inputs 16 and 17. The gear ratio is then
activated by means of the Switching Input (I2). The slave will then proceed at the permitted
acceleration to this new gear ratio. The offset is related to the first gear ratio after SyncStart. Therefore
a stop and then start must be performed if the offset must relate to the latest gear ratio it the gear ratio
has been changed.
Error procedure
Errors of tracking, over current etc. make the drive stop. The Ready output (O8) is set low.
Reset is done with Input 27 or fieldbus bit 1.9.
Reset is also possible with of the local control panel of the drive. This is only possible if the local stop
function is the [STOP/RESET] key disabled in parameter 014.
Note: You cannot stop the drive via the local control panel if local stop is disabled.
In case the drive has stopped because of earth fault or short-circuit, disconnect the drive from the
mains before you reset!