
4. SERVO FUNCTION DETAILS B-65150E/04
− 240 −
(6) Using a separate position detector
(1,000,000 pulses or more per motor revolution)
When a machine is used for which the number of feedback pulses from
a separate position detector per motor revolution exceeds 1,000,000,
stable control cannot be achieved if serial pulse coder A or the αA1000
(pulse coder built into the motor) is used as the velocity detector.
In this case, a velocity detector with a greater number of pulses is
required. When a velocity detector with a greater number of pulses is
used, a special system, like that shown Fig. 4.16, must be configured.
This function is option.
Fig. 4.16 Special system for super-precision machining
Thus, the one axis of this system is driven using the normal two axes.
To configure a system like that described above, modify the settings of
the following parameters.
Function bits
Series
15-B
Series
16-C,
18-C
Function
bit
Axis Funciton
No. 1807
−
#3 = 1
First axis and
second axis
Enables a separate position
detector.
No. 1815 No. 1815 #1 = 1
First axis and
second axis
Enables a separate position
detector.
No. 1953 No. 2009 #0 = 1 Second axis Enables dummy bits.
No. 1884 No. 2006 #3 = 1 First axis Enables the system.
No. 1709 No. 2019 #4 = 1 First axis Enables the system.
Position gain
Separate position detector
Velocity
control
Current
control
Motor
Separate detector
feedback input for
the first axis
Separate detector
feedback input for
the second axis
Motor feedback input
for the first axis
Serial pulse coder A
Separate velocity detector
−
+
−
+
Optional function