YASKAWA E-V Series User Manual page 139

5 Operation
5.4.3 Electronic Gear
Electronic gear ratio:
(4) Procedure for Setting the Electronic Gear Ratio
Set value electric gear differs depending on the machine specifications. Use the following procedure to set the
electronic gear ratio.
Step
1
2
3
4
(5) Electronic Gear Ratio Equation
Refer to the following equation to determine the electric gear ratio.
Reference pulse
L mm
Ps mm
(6) Electronic Gear Ratio Setting Example
An example of electronic gear ratio setting is given below.
Step
1
2
3
4
5-36
B Pn20E
=
A Pn210
Electronic gear ratio setting range: 0.001
If the electronic gear ratio is outside this range, a parameter setting error (A.040) will be
output, and the SERVOPACK will not operate properly. In this case, modify the load con-
figuration or reference unit.
Check the scale pitch.
Check the scale pitch of linear scale used.
Determine the reference unit used.
Determine the reference unit from the host controller, considering the
machine specifications and positioning accuracy.
Calculate the electronic gear ratio.
Use the electronic gear ratio equation to calculate the ratio.
Set parameters.
Set parameters Pn20E and Pn210 using the calculated values.
+
B
A
−
mm/P
mm/P Reference unit
Movement distance
Scale pitch
L
B L
× ( ) = 256 ×
Ps
A
B 256 × L ×
( ) =
=
A
Ps × L
Operation
Check the scale pitch.
Determine the reference
unit.
Calculate the electronic
gear ratio.
Set parameters.
Travel distance per reference unit
=
Scale pitch
Operation
Linear servomotor
Posi-
Speed
tion
loop
loop
Movement distance L mm
×256
L
mm/scale pitch
Ps
Set A and B with the following parameters.
256 ×
Ps
A Pn210
Load Configuration
0.02 mm (20 μm)
1 reference unit: 0.001 mm (1 μm)
1(μm)
B
× 256
=
A 20(μm)
Pn20E 256
Pn210 20
×
256
≤
Electronic gear ratio (B/A)
B Pn20E
≤
4000