YASKAWA SGD7S-1R9D Product Manual page 162

5.14 Setting Unit Systems
5.14.1 Setting the Position Reference Unit
Electronic Gear Ratio Setting Examples
Setting examples are provided in this section.
• Rotary Servomotors
Step
1
2
3
4
5
6
*
For a Rotary Servomotor with an encoder resolution of 24 bits (16,777,216), Pn20E (Electronic Gear Ratio
(Numerator)) is automatically set to 16 and Pn210 (Electronic Gear Ratio (Denominator)) is automatically set to 1.
Therefore, the encoder resolution will be equivalent to 20 bits (1,048,576). Consider this when you set the position
reference unit in position user unit (2701 hex).
• Linear Servomotors
A setting example for a Serial Converter Unit resolution of 256 is given below.
Step
1
2
3
4
*
For a Linear Servomotor, both Pn20E (Electronic Gear Ratio (Numerator)) and Pn210 (Electronic Gear Ratio
(Denominator)) are automatically set to 1. Consider this when you set the position reference unit in position user
unit (2701 hex).
5-46
Description
Encoder:
24 bits
• Ball screw lead: 6 mm
Machine
• Gear ratio: 1/1
Specifications
Encoder Resolution 16,777,216 (24 bits)
0.001 mm (1 μm)
Reference Unit
Travel Distance per
6 mm/0.001 mm =
Load Shaft Revolution
6,000
(Reference Units)
B
Electronic Gear Ratio*
A
Numerator: 1,048,576
Position User Unit
(2701 hex)
Denominator: 6,000
Description
0.02 mm (20 μm)
Linear Encoder Pitch
0.001 mm (1 μm)
Reference Unit
B
Electronic Gear Ratio*
A
Numerator: 256
Position User Unit
(2701 hex)
Denominator: 20
Machine Configuration
Ball Screw
Reference unit: 0.001 mm
Load shaft
Ball screw lead:
Load shaft
6 mm
• Rotation angle per revo-
lution: 360°
• Gear ratio: 1/100
16,777,216 (24 bits)
0.01°
360°/0.01° = 36,000
B
16,777,216 1 1
=
= × ×
A
6,000 16 1
Numerator:
104,857,600
Denominator: 36,000
Machine Configuration
Reference unit:
0.02 mm (20 m)
Forward direction
1 (μm) 1
×
=
20 (μm)
1
Rotary Table Belt and Pulley
Reference unit: 0.005 mm
Reference unit: 0.01°
Gear ratio:
1/100
Gear ratio:
1/50
Encoder: 24 bits
• Pulley dia.: 100 mm
(Pulley circumference:
314 mm)
• Gear ratio: 1/50
16,777,216 (24 bits)
0.005 mm (5 μm)
314 mm/0.005 mm =
62,800
B
16,777,216 1 100
=
× ×
1 A
36,000 16
Numerator: 52,428,800
Denominator: 62,800
Load shaft
Pulley dia.:
100 mm
Encoder: 24 bits
16,777,216 1 50
× ×
1
36,000 16