Yaskawa Sigma II Series Servo System - Manual (Page 116)

Sigma II User’s Manual Chapter 5: Parameter Settings and Functions
5 - 30
5. Electronic gear ratio is given as:
If the gear ratio of the motor and the load shaft is given as:
where m is the rotation of the motor and n is the rotation of the load shaft,
Electronic gear ratio =
Note: Make sure the electronic gear ratio satisfies the following condition:
0.01 ≤ Electronic gear ratio ≤ 100
The servo amplifier will not work properly if the electronic gear ratio exceeds this range. In that case,
modify either the load configuration or the reference unit.
6. Set the parameters.
Reduce the electronic gear ratio to the lower terms so that both A and B are
integers smaller than 65535, then set A and B in the respective parameters:
Set the electronic gear ratio according to equipment specifications.
• B = [(Number of encoder pulses) × 4] × [motor speed]
• A = [Reference units (travel distance per load shaft revolution)] × [load shaft
revolution speed]
Parameter Signal Setting Control Mode
Pn202 Electronic Gear Ratio (Numerator)
Range: 1 to 65535
Default Setting: 4
Position Control
Pn203 Electronic Gear Ratio (Denominator)
Range: 1 to 65535
Default Setting: 1
Position Control
B
A
---
⎝ ⎠
⎛ ⎞
m
n
---
B
A
---
⎝ ⎠
⎛ ⎞
Number of encoder pulses
×
4
Travel distance per load shaft revolution (reference unit)
× m
n
---
B
A
---
⎝ ⎠
⎛ ⎞
B
A
( )
Pn202
Pn203
Electronic Gear Ratio (Numerator)
Electronic Gear Ratio (Denominator)
M
Reference
input pulse
SGDH Servo amplifier
Electronic
gear
SGM H
servomotor
Electronic gear ratio = =
B
A
---
⎝ ⎠
⎛ ⎞
Pn202
Pn203