YASKAWA SGDV User Manual page 115

(1) Electronic Gear Ratio
Set the electronic gear ratio using Pn20E and Pn210.
Electronic Gear Ratio (Numerator)
Pn20E
Setting Range
1 to 1073741824
Electronic Gear Ratio (Denominator)
Pn210
Setting Range
1 to 1073741824
If the gear ratio of the servomotor and the load shaft is given as n/m where m is the rotation of the servomotor
and n is the rotation of the load shaft,
B
Electronic gear ratio:
A
Encoder Resolution
Encoder resolution can be checked with servomotor model designation.
SGMMV
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.
(2) Electronic Gear Ratio Setting Examples
The following examples show electronic gear ratio settings for different load configurations.
Step Operation
Check machine specifica-
1
tions.
Check the encoder reso-
2
lution.
Determine the reference
3
unit used.
Calculate the travel dis-
4 tance per load shaft revo-
lution. (Reference unit)
Calculate the electronic
5
gear ratio.
6 Set parameters.
Setting Unit
1
Setting Unit
1
Pn20E
Encoder resolution
=
=
Pn210
Travel distance per load
shaft revolution (reference units)
Symbol Specification
2 17-bit absolute
Ball Screw
Reference unit: 0.001 mm
Load shaft
17-bit encoder Ball screw
pitch: 6 mm
Ball screw pitch: 6 mm
Gear ratio: 1/1
131072 (17-bit)
Reference unit: 0.001 mm
(1 μm)
6 mm/0.001 mm=6000
B 131072 1
=
A 6000 1
Pn20E: 131072
Pn210: 6000
5.4 Position Control (Pulse Train Reference)
Position
Factory Setting When Enabled
4 After restart
Position
Factory Setting When Enabled
1 After restart
m
×
n
Encoder Resolutions
131072
≤
Electronic gear ratio (B/A)
Load Configuration
Disc Table
Reference unit: 0.01°
Gear ratio:
1/100
Load shaft
17-bit encoder
Rotation angle per revolu-
tion: 360°
Gear ratio: 1/100
131072 (17-bit)
Reference unit: 0.01°
360°/0.01°=36000
B 131072 100
=
A 36000 1
Pn20E: 13107200
Pn210: 36000
Classification
Setup
Classification
Setup
≤
4000
Belt and Pulley
Reference unit: 0.005 mm
Load shaft
Gear ratio
1/50
Pulley diameter:
100 mm
17-bit encoder
Pulley diameter: 100 mm
(pulley circumference: 314
mm)
• Gear ratio: 1/50
131072 (17-bit)
Reference unit: 0.005 mm
(5 μm)
314 mm/0.005 mm=62800
B 131072 50
=
A 62800 1
Pn20E: 6553600
Pn210: 62800
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5