Chapter 4 Operation
- 72 -
4.6.2 Setting the Electronic Gear
（
1
1
1
1
）
Electronic
Electronic
Electronic
Electronic Gear
Gear
Gear
Gear
The electronic gear enables the workpiece travel distance per input reference pulse from the host
controller to be set to any value.
One reference pulse from the host controller, i.e., the minimum position data unit, is called a reference
unit.
（
2
2
2
2
）
Related
Related
Related
Related Parameters
Parameters
Parameters
Parameters
Pn201
Electronic Gear Ratio(Numerator)
Setting
Setting
Setting
Setting Range
Range
Range
Range
Setting
Setting
Setting
Setting Unit
Unit
Unit
Unit
Factory
Factory
Factory
Factory Setting
Setting
Setting
Setting
Setting
Setting
Setting
Setting Validation
Validation
Validation
Validation
1
～
65535
—
1
After restart
Pn202
Electronic Gear Ratio(Denominator)
Setting
Setting
Setting
Setting Range
Range
Range
Range
Setting
Setting
Setting
Setting Unit
Unit
Unit
Unit
Factory
Factory
Factory
Factory Setting
Setting
Setting
Setting
Setting
Setting
Setting
Setting Validation
Validation
Validation
Validation
1
～
65535
—
1
After restart
If the deceleration 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.
Electronic gear ratio:
202
201
Pn
Pn
A
B
=
n
m
units
reference
revolution
shaft
load
per
ce
dis
Travel
pulses
encoder
of
No
×
×
=
)
(
tan
4
.
* If the ratio is outside the setting range, reduce the fraction (both numerator and denominator) until you
obtain integers within the range.
* Be careful not to change the electronic gear ratio (B/A).
■Important
Electronic gear ratio setting range: 0.01≤electronic gear ratio(B/A)≤ 100
If the electronic gear ratio is outside this range, the servodrive will not operate properly. In this case,
modify the load configuration or reference unit.
When the Electronic Gear is Not Used
When the Electronic Gear is Used
workpiece
workpiece
N o . of encoder
p u ls e s
：
3 2 7 6 8
Ball screw pitch
：
6m m
N o . of encoder
p u ls e s
：
3 2 7 6 8
Ball screw pitch
：
6 m m
One revolution is 6m m . Therefore 1 0 ÷6
＝
1.6 6 6 6 revolutions .
3 2 7 6 8 ×4 pulses is one revolution .
Therefore, 1.6 6 6 6 ×3 2 7 6 8 ×4
＝
218448
p u ls e s. 218448 pulses are input as
reference pulses.
The equation must be calculated at the
host controller .
To move a workpiece 1 0 mm :
The reference unit is 1 µm. Therefore, to
move the workpiece 1 0 mm (1 0 0 0 0 µm),
1p u lse =1µm, so 1 0 0 0 0 /1
＝
10000 p u ls e s.
Input 10000 pulses per 1 0 mm of
workpiece movement .
To move a workpiece 1 0 mm using
reference units:
Reference unit
：
1µm
Position
Position
