SD710 Series Servo Drive User Manual Chapter 5 Commissioning and Operation
18
Select the pulse input form of the servo unit according to the pulse output form of the upper system.
5.2.5 Electronic Gear Ratios
For a machine reduction ratio of n/m on the motor shaft and load side (n revolutions of the load shaft for m revolutions of
the motor), the set value of the electronic gear ratio can be got by the following equation.
Electronic gear ratio
𝐵
𝐴
=
Pn204
Pn206
=
Encoder resolution
One turn movement of load shaft (command unit)
×
𝑚
𝑛
Table 5-8 Electronic Gear Ratio Setting Routine
Steps
Elements
Mechanical system components
Ball screw
Round table
Belt + Pulley
-
-
1
Machine
specifications
Ball screw lead: 6mm
Reduction ratio: 1/1
Rotation angle of 1 turn: 360°
Deceleration ratio: 1/20
Pulley diameter: 100mm
(Pulley circumference:
314mm)
Reduction ratio: 1/20
2
Encoders
resolution
16777216 (24 bits)
16777216 (24 bits)
16777216 (24 bits)
3
Command unit
0.001mm
0.01°
0.005mm
4
Travel of 1
rotation of
load axis
(command
unit)
6mm/0.001mm = 6000
360° /0.01° = 36000
314mm/0.005mm = 62800
5
Electronic
gear ratio
𝐵
𝐴
=
16777216
6000
×
1
1
𝐵
𝐴
=
16777216
36000
×
20
1
𝐵
𝐴
=
16777216
62800
×
20
1
6
Parameters
Pn204: 16777216
Pn204: 16777216
Pn204: 16777216
1
1
CW+CCW
CW
CCW
CW
CCW
1
4
Orthogonal
coding 4x
A Phase
B Phase
90°
90°
A Phase
B Phase