YASKAWA SGMJV User Manual page 112

4 Operation
4.4.3 Electronic Gear
 Encoder Resolution
Encoder resolution can be checked with servomotor model designation.
SGM V
SGMPS
SGMCS
(2) Electronic Gear Ratio Setting Examples
The following examples show electronic gear ratio settings for different load configurations.
Step
1
2
3
4
5
6
4-26
Symbol
3
D
A
Symbol
2
C
Symbol
3
D
Electronic gear ratio setting range: 0.001
If the electronic gear ratio is outside this range, a parameter setting error 1 (A.040) will
be output.
Operation
20-bit encoder
 Ball screw pitch: 6 mm
Check machine specifica-
tions.  Gear ratio: 1/1
Check the encoder reso-
1048576 (20-bit)
lution.
Determine the reference Reference unit: 0.001 mm
(1 μm)
unit used.
Calculate the travel dis-
tance per load shaft revo- 6 mm/0.001 mm=6000
lution. (Reference unit)
Calculate the electronic
B
gear ratio.
A
Pn20E: 1048576
Set parameters.
Pn210: 6000
Specification
20-bit absolute
20-bit incremental
13-bit incremental
Specification
17-bit absolute
17-bit incremental
Specification
20-bit absolute
20-bit incremental
Load Configuration
Ball Screw
Reference unit: 0.001 mm
Reference unit: 0.01°
Load shaft
Ball screw
pitch: 6 mm
Load shaft
Rotation angle per revolu-
tion: 360°
Gear ratio: 1/100
1048576 (20-bit)
Reference unit: 0.01°
360°/0.01°=36000
1048576 1 B
=
×
=
6000 1 A
Pn20E: 104857600
Pn210: 36000
Encoder Resolutions
1048576
1048576
8192
Encoder Resolutions
131072
131072
Encoder Resolutions
1048576
1048576
≤
Electronic gear ratio (B/A)
Disc Table Belt and Pulley
Reference unit: 0.005 mm
Gear ratio:
Gear ratio
1/100
1/50
20-bit encoder
Pulley diameter: 100 mm
(pulley circumference: 314
mm)
• Gear ratio: 1/50
1048576 (20-bit)
Reference unit: 0.005 mm
(5 μm)
314 mm/0.005 mm=62800
1048576 100 B
×
=
36000 1 A
Pn20E: 52428800
Pn210: 62800
≤
4000
Load shaft
Pulley diameter:
100 mm
20-bit encoder
1048576 50
×
62800 1