409
FX3G/FX3U/FX3UC Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
14 Handy Instruction – FNC 60 to FNC 69
14.7 FNC 66 – ALT / Alternate State
11
FNC30-FNC39
Rotation and
Shift
12
FNC40-FNC49
Data Operation
13
FNC50-FNC59
High Speed
Processing
14
FMC60-FNC69
Handy
Instruction
15
FNC70-FNC79
External FX I/O
Device
16
FNC80-FNC89
External FX
Device
17
FNC100-FNC109
Data
Transfer 2
18
FNC110-FNC139
Floating Point
19
FNC140-FNC149
Data
Operation 2
20
FNC150-FNC159
Positioning
Control
Caution
1. When using (continuous operation type) ALT instruction
• When ALT instruction is used, a specified bit device is alternated in every operation cycle.
To alternate a specified device by turning the command ON or OFF, use the (pulse operation type) ALTP
instruction, or use a pulse operation type command contact such as LDP.
Program examples
1. Start and stop by one input
1) When the pushbutton switch X000 is pressed, the start output Y001 is set to ON.
2) When the pushbutton switch X000 is pressed again, the stop output Y000 is set to ON.
2. Flicker operation
1) When the input X006 is set to ON, the contact of the timer T2 turns ON instantaneously every 5 seconds.
2) Every time the contact of T2 turns ON, the output Y007 is set to ON or OFF alternately.
3. Alternating output operation using auxiliary relays (M) (operation equivalent to ALT instruction)
The circuit below is provided as an example of alternating operation using basic instructions and auxiliary relays (M)
which is equivalent to ALT instruction.
1) When X000 is set to ON, M0 turns ON and remains ON for only one operation cycle.
2) When M0 turns ON for the first time, Y000 is latched. When M0 turns ON the second time, Y000 becomes
unlatched.
M 0
Y000
Stop
Y001
M 0
Start
X000
FNC 66
ALTP
M 0
X006
T 2
K50
FNC 66
ALT
Y007
T2
X006 T2
ONON
ON
X006
T 2
ON
Y007
5s
5s 5s 5s 5s 5s 5s
X000
X000
M 1
M 0 Y000
M 0 Y000
M 0
M 1
Y000