Mitsubishi Electric M800W Series, Connection And Set Up Manual

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M800W/M80W Series Connection and Setup Manual
33 Synchronous Control and Multiple-axis Synchronization Control
576 IB-1501268-K
(2) Speed command synchronous control
This is used when reducing the scale of the full-closed system or when the machine's rigidity, etc. cause the
mutual interference to the axes positions.
This drives the master axis and the slave axis in parallel using the common position feedback. Since the
feedrate of each axis is controlled by the speed feedback of each axis, the stable control is available.
This can be used when the settings of the NC and the servo drive unit are changed.
Speed command synchronous control diagram
(3) Current command synchronous control
This drives the master and slave axes in parallel by reference to the speed feedback from the encoder onto the
master axis side on the slave axis. Since that speed feedback is not the slave axis's itself, the slave axis easily
vibrates.
Also, as the slave axis is easily influenced by the disturbance, this is not appropriate for the machine tools
which need the positioning accuracy or the interpolation accuracy.
This can be used when the setting of the NC and the servo drive unit are changed.
Current command synchronous control diagram
The "compensation" in the (1), (2) and (3) diagrams indicates the pitch error compensation, the thermal expansion
compensation, the backlash compensation and the external machine coordinate compensation.
The axes which can set the compensation during the synchronous control differ according to the synchronous control
type.
CNC
M
M
Drive unit
Master axis
Slave axis
Detector
Detector
Drive unit
Compensation
Position
command
Position
detector
Compensation
CNC
M
M
Drive unit
Master axis
Slave axis
Detector
Drive unit
Detector
Position
command
Compensation
Compensation