Mitsubishi FX3G Series User Manual page 86

FX /FX /FX PLC User's Manual - Positioning Control Edition
3G 3U 3UC
Built-in Positioning Functions
2. Zero return instruction (ZRN instruction)
Zero return will be performed in the reverse rotation direction only.
(During zero return, the value indicated by the current value register will be decreased.)
To perform zero return in the forward rotation direction using the ZRN instruction (zero return instruction):
To perform zero return in the forward rotation direction, create a program to control the output (Y) relay set as
a "rotational direction signal" as follows:
1) Turn on Y
2) Refresh Y
3) Execute the ZRN instruction (zero return instruction).
4) Using the execution completion flag (M8029) of the ZRN instruction (zero return instruction), reset
Y
Example program:
The following program uses Y004 as the rotational direction signal for Y000.
Command
input
M8340
Y000 output
pulse monitor
B - 48
→ To use
→ To use a high-speed output special adapter, refer to Section 4.9.
(rotational direction signal).
output using the REF (FNC50) instruction.
(rotational direction signal).
FNC156
S
1•
DZRN
M8029
M8329
4.3 Various Special Relays for Operation Commands
→ For details on programming, refer to Section 4.7.
main unit (transistor output), refer to Section 4.8.
the
RST M10
RST M11
SET Y004
FNC 50
Y000 K8
REFP
S S Y000
2• 3•
RST Y004
SET M10
RST Y004
SET M11
4 Before Programming
Turns on (sets) Y004 as the
a)
rotational direction signal of Y000
(pulse output destination).
Refreshes Y000 to Y007.
b)
Executes ZRN instruction.
c)
Resets the rotational direction
d)
signal (Y004) using the instruction
execution complete flag.
Origin data reading completion flag
Resets the rotational direction signal
(Y004) using the instruction
execution abnormal end flag.
Abnormal end of zero return