
8.3 Parameter Settings for Fully-closed Loop Control
8-21
8
Fu
lly-close
d L
oop
Co
ntro
l
8.3.5
Electronic Gear
Refer to
4.2.4 Electronic Gear
for the purpose of setting the electronic gear.
The following formula is used to calculate the electronic gear ratio in fully-closed loop control.
Note: Set Pn20E (numerator B) and Pn210 (denominator A) to integral values.
The setting range is defined by 0.001
≤
≤
4000.
The following table shows the various external encoder sin wave pitches and the number of divisions.
External Encoder Sine Wave Pitch and Number of Divisions
Calculate the electronic gear ratio with the values in the following table.
∗1.
Models for serial converter units.
∗2.
When using the encoder pulse output with these external encoders, the setting range of Pn281 is restricted. For
details, refer to
8.3.3 Setting Encoder Output Pulses (PAO, PBO, and PCO)
.
∗3.
Model for sensor head with interpolator.
∗4.
Model for interface unit by Heidenhain.
∗5.
For details on this external encoder, contact Mitutoyo.
∗6.
Model for rotational external encoder.
Refer to the manuals for the external encoder and serial converter unit for details on the sine wave pitch and
the number of divisions of the external encoder.
A
B
Pn210
Pn20E
External encoder sine wave pitch
Travel distance per reference unit
×
Number of divisions
Electronic gear ratio
==
=
Rotation
B
A
Type of
External
Encoder
Manufacturer
External Encoder
Model
Sine Wave
Pitch [
μ
m]
Model of Relay
Device between
SERVOPACK and
External Encoder
Number
of
Divisions
Resolution
Incremental
Heidenhain
LIDA48
20
JZDP-D003-
-E
∗
1
256
0.078
μ
m
LIDA18
40
JZDP-D003-
-E
∗
1
256
0.156
μ
m
LIF48
4
JZDP-D003-
-E
∗
1
256
0.016
μ
m
Renishaw plc
RGH22B
20
JZDP-D005-
-E
∗
1
256
0.078
μ
m
Magnescale Co., Ltd.
SR75-
LF
*2
80
–
8192
0.0098
μ
m
SR75-
MF
80
–
1024
0.078
μ
m
SR85-
LF
*2
80
–
8192
0.0098
μ
m
SR85-
MF
80
–
1024
0.078
μ
m
SL700
*2
,
SL710
*2
,
SL720
*2
,
SL730
*2
800
PL101-RY
*3
8192
0.0977
μ
m
Absolute
Heidenhain
LIC4100
20.48
EIB3391Y
*4
4096
0.005
μ
m
Mitutoyo Corporation
ST781A/ST781AL
256
–
512
0.5
μ
m
ST782A/ST782AL
256
–
512
0.5
μ
m
ST783/ST783AL
51.2
–
512
0.1
μ
m
ST784/ST784AL
51.2
–
512
0.1
μ
m
ST788A/ST788AL
51.2
–
512
0.1
μ
m
ST789A/ST789AL
*5
25.6
–
512
0.05
μ
m
Magnescale Co., Ltd.
SR77-
LF
*2
80
–
8192
0.0098
μ
m
SR77-
MF
80
–
1024
0.078
μ
m
SR87-
LF
*2
80
–
8192
0.0098
μ
m
SR87-
MF
80
–
1024
0.078
μ
m
RU77-4096ADF
*6
–
–
256
20 bits
RU77-4096AFFT01
*6
–
–
1024
22 bits