Setting Of Electronic Gear (For Melservo Series - Mitsubishi MELSEC-F FX3U Series User Manual

FX /FX Series PLC User's Manual - Positioning Control Edition
3U 3UC
Built-in Positioning Function
4.6.2

Setting of Electronic Gear (For MELSERVO Series)

Use the electronic gear of the servo motor to set the transfer distance per pulse.
For details on electronic gear setting, refer to the manual of your servo motor or servo amplifier, and set the
optimum value considering the application.
Setting example 1:
To set the transfer distance per pulse to 10 µm (if the machine uses a ball screw):
Machine specifications
Servo amplifier
Rated rotational speed of servo motor
Lead of ball screw (Pb)
Reduction ratio (mechanical gear) (n)
Resolution of servo motor (Pt)
CMX
×
=
0
CDV
Set the electronic gear as follows:
CMX = 8, CDV = 1
In this case, when the main unit outputs the maximum output
pulse frequency (100 kHz), the servo motor rotational speed
will be as follows:
CMX
N = ×
0
CDV
8 60
= ×
1 4000
= 12000r/min > 3000r/min (Rated rotational speed of servo motor)
It is not necessary to restrict the maximum speed on the PLC side because the servo motor rotational speed
is less than the rated rotational speed.
Pulse output destination device
Y000
Y001
Y002
Y003
*1. Devices related to Y003 (pulse output destination) are valid only if two FX
connected to the FX
MR-C Series
3000r/min
10mm (0.4")
1/2
4000pls/rev
Pt 4000
-3 ×
= 10×10
n×P 1/2×10
b
60
× f
0
Pt
× 100000
Maximum speed setting device
*1
PLC.
3U
4.6 Setting of Various Items on Servo Amplifier (Drive Unit) Side
n=NL/NM=1/2
Servo motor
Pt = 4000 (pls/rev)
8
f0 : Command pulse frequency [Hz]
=
1
(Open collector system)
CMX : Electronic gear
(numerator of command pulse
multiplying factor)
CDV : Electronic gear
(denominator of command pulse
multiplying factor)
N0 : Servo motor rotational speed [r/min]
0 : Transfer distance per pulse [mm]
D8344,D8343
D8354,D8353
D8364,D8363
D8374,D8373
4 Before Programming
n
NL
Pb=10[mm](0.4")
NM
-2HSY-ADP adapters are
3U
B - 55
A
B
Apx.