Mitsubishi Electric Melsec FX Series Beginners Manual page 54

Learning to Use the FX Family for Positioning Control
Programming example for a FX
The following program is similar to the previous one except that it is programmed only in ladder logic
and does not follow a specific sequence of step ladder states. Additionally, it includes control for rel-
ative positioning with JOG(+) and JOG(-) commands, a DOG search zero return function, and utiliza-
tion of the DTBL instruction.
When using an FX
grammed with limit switches wired to the PLC as follows
Servo motor
Fig. 4-7: Configuration example
The DTBL instruction helps to simplify the programming and is set up beforehand (along with posi-
tioning parameters such as the bias speed, acceleration/deceleration, etc.) with GX Developer, GX IEC
Developer or GX Works2.
In this example, positioning may be performed arbitrarily along the path in fig. 4-8.
Using the JOG command, the workpiece is moved to any relative position. This is not illustrated in the
figure below.
Origin after
zero return
Required hardware and software are as follows:
● FX
3G
or
● FX
3U(C)
● GX Developer 8.23Z or later
or
● GX IEC Developer
or
● GX Works2
4 - 12
, FX , FX
3G 3GC 3GE
Reverse rotation limit 2 Reverse rotation limit 1
(Servo amplifier side)
Reverse rotation
500,000
Forward
positioning
Output pulse frequency:
100,000 Hz
100
Reverse
positioning
Acceleration/deceleration time:
100 ms
, FX FX PLC
3GC, 3GE
PLC version 2.20 or later
, FX , FX3 or FX
3G 3GC GE 3U(C)
, or FX PLC, the DOG search zero return function can be pro-
3U(C)
(Programmable
controller side)
LSR
Forward rotation
Fig. 4-8:
Bias speed
500 Hz
500 Hz
MELSEC FX PLC positioning
PLC
Forward rotation limit 1 Forward rotation limit 2
(Programmable (Servo amplifier side)
controller side)
LSF
Positioning pattern
MITSUBISHI ELECTRIC
413060da.eps
413070da.eps