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Speed/torque coupling, master-slave (TE3)
23.10 Response in conjunction with other functions
Turning, Milling, Nibbling
Function Manual, 11/2012, 6FC5397-1CP10-5BA0
401
23.10
Response in conjunction with other functions
Function Generator
To calibrate the speed control circuit for a closed master-slave coupling, a low value should
be set in slave axis MD37268 MS_TORQUE_WEIGHT_SLAVE. Traversing of a coupled-
motion slave axis is not prevented by the torque compensatory controller in this case.
Reference point approach
If the coupling is closed, only the master axis can be referenced. Referencing of slaves axes
is suppressed. The referencing requirement does not have to be explicitly canceled for the
slave axis in order to do this. The referencing status of coupled slave axes remains
unchanged. The slave axis position is generally not the same as the master axis position.
This difference in position is not significant. If the coupling is not closed, each axis can be
referenced separately as usual.
Compensation
Position offsets of the slave axis, such as spindle pitch errors, backlash, temperature and
sag offsets are computed but not active because there is no position controller.
Correct calculation of the backlash compensation requires that the backlash of the slave axis
is always overtraveled by the motion of the master axis in coupled mode. Disconnecting the
coupling during an axis reversal error will generate an incorrect actual value for the slave
axis.
Dynamic stiffness control
The Kv factor of the master axis is copied to the slave axis for an existing coupling and is
thus also active in the slave drive. This is an attempt to achieve the same control response in
the drive of the master and slave axis as far as possible. MD32640 must be configured
identically in all coupled axes.
Speed precontrol
The feedforward control in the slave axis does not have to be activated explicitly. The current
settings of the master axis apply. The speed feedforward value of the master axis is already
incorporated in the speed setpoint of the slave axis.
The mechanical situation changes in coupled mode. Axial settings must be adjusted
accordingly. All coupled drives should have the same speed control dynamics.