Danfoss MCO 305, Design Manual, Page: 160 / 242

MCO 305 Design Guide
__ Software Reference __
160
MG.33.L4.02 – VLT
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SYNCP
Summary Angle/position synchronization with the master
Syntax SYNCP
Description The command completes an angle/position synchronization with the master. In
doing so the position according to the gear factors to the master is kept synchro-
nous, that means after an external disturbance the program subsequently tries to
recover the corresponding stretch.
However, in doing so the values set for velocity VEL, and acceleration ACC or DEC
are not exceeded.
The following parameters affect the behavior:
par. 33-10
Syncfactor Master and
par. 33-11 Syncfactor Slave (gear factors)
par. 33-12 Position Offset for Synchronization
par. 33-13 Accuracy Window for Position Sync. (accuracy for flag)
par. 32-68 Reverse Behavior for Slave
During synchronization the program proceeds as follows:
When the SYNCP command is started, the actual master position is determined and
is retained. From the master velocity, and in consideration of the acceleration
allowed, the necessary slave velocity is calculated in order to reach the master
position. The slave is accelerated so long until the calculated position has been
reached or until it is close enough to the reference position to reach it.
NB!:
As soon as the deviation between the position of the slave and master is less than
par. 33-13 SYNCACCURACY, the ACCURACY flag is set.
If par. 32-68 REVERS is set so that it is not possible to drive in reverse, but for
some reason the slave is further than the master (e.g. because only the master
has moved in reverse) then the slave will wait at velocity 0.
In doing so the slave takes its own acceleration time into consideration and will
start moving if necessary before the correct position has been reached if the
master already has a higher velocity.
Instead of using this catch-up procedure it is also possible to move the slave with
CVEL to approximately the same velocity as the master and then trigger SYNCP.
A change in the par. 33-12 Position Offset for Synchronization during the synchro-
nization leads to a new synchronization procedure with ramps (see above).
NB!:
SYNCP should only be called up once since the synchronizing continues until the
next motion or stop command. All additional SYNCP commands cause the synchro-
nization to start over again from the beginning and this is not normally intended,
as you reset the actual SYNCERR.
Command Group SYN