
(4)CMR
1820 Command multiply ratio
PRM
1) When CMR is 1/2 to 1/27
2) When CMR is 0.5 to 48
(5)Turn off the power then back on.
(6)N/M of feed gear (F⋅FG)
2084 n for flexible feed gear
PRM
2085 m for flexible feed gear
PRM
Setting for the α pulse coder in the semi–closed mode
Necessary position feedback pulses
per motor revolution
(Note 1)
F⋅FG numerator (v 32767)
(as irreducible fraction)
1,000,000 (Note 2)F⋅FG denominator (v 32767)
=
NOTE
1 For both F⋅FG number and denominator, the maximum
setting value (after reduced) is 32767.
2 αi pulse coders assume one million pulses per motor
revolution, irrespective of resolution, for the flexible feed
gear setting.
3 If the calculation of the number of pulses required per motor
revolution involves π, such as when a rack and pinion are
used, assume π to be approximately 355/113.
[Example]
For detection in 1 µm units, specify as follows:
Ball screw lead
(mm/rev)
Number of necessary
position pulses
(pulses/rev)
F⋅FG
10
20
30
10000
20000
30000
1/100
2/100 or 1/50
3/100
[Example]
If the machine is set to detection in 1,000 degree units with a gear
reduction ratio of 10:1 for the rotation axis, the table rotates by 360/10
degrees each time the motor makes one turn.
1000 position pulses are necessary for the table to rotate through one
degree.
The number of position pulses necessary for the motor to make one turn
is:
360/10 1000 = 36000 with reference counter = 36000
Set value=
1
CMR
+100
Set value=2×CMR
F⋅FG numerator
F⋅FG denominator
=
36000
1,000,000
=
36
1000
GFKE-0222-EN
9. DIGITAL SERVO
675