Mitsubishi Electric MELSEC FX3U Programming Manual page 581

FX /FX /FX Series Programmable Controllers
3G 3U 3UC
Programming Manual - Basic & Applied Instruction Edition
Explanation of function and operation
Command
input
FNC156
ZRN
Caution on writing during RUN
During RUN, avoid writing while the ZRN (FNC156) instruction is executed (that is, while pulses are output).
Note that if writing is executed during RUN to a circuit block including the FNC156 instruction while pulses are
output, the PLC decelerates and stops pulse output.
Function change depending on the version
The function of FNC156 instruction is changed depending on the version as shown in the table below.
Applicable version
FX FX
3G 3U
Ver.1.00 Ver.2.20
or later or later
S S S
1 2 3
→ For explanation of the instruction and the contents of function change,
Item
FX
3UC
Clear signal output
Ver.2.20
destination
or later
specification function
20 Positioning Control – FNC150 to FNC159
D
refer to the Positioning Control Edition.
Outline of function
When a special auxiliary relay corresponding to
the clear signal output destination is changed to an output number
specified by a special data register corresponding to
20.5 FNC156 – ZRN / Zero Return
is set to ON,
D
D .
579
11
12
13
14
15
16
17
18
19
20