105
FX3G/FX3U/FX3UC Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
4 Devices in Detail
4.7 High Speed Counter [C] (FX3U/FX3UC PLC)
1
Introduction
2
Overview
3
Instruction
List
4
Devices
in Detail
5
Specified the
Device &
Constant
6
Before
Programming
7
Basic
Instruction
8
FNC00-FNC09
Program Flow
9
FNC10-FNC19
Move & Compare
10
FNC20-FNC29
Arith. & Logic
Operation
• When the reset input X011 turns ON and RST instruction is executed, the current value of the counter is reset to "0"
and the output contact is restored.
• In a latch type high speed counter, the current value, output contact operation and reset status of the counter are
latched (battery backed) by the backup battery built in the PLC.
2. 1-phase 2-count input
These counters are 32-bit binary bi-directional counters, and the operation of the output contact for the current value is
equivalent to that in 1-phase 1-count input type high speed counters described above.
• While X012 is ON, C246 executes up-count when the input X000
turns from OFF to ON, and executes down-count when the input
X001 turns from OFF to ON.
• The up/down-count operation of C246 to C250 can be checked with
M8246 to M8250.
ON status: Down-counting
OFF status: Up-counting
• While X012 is ON, C249 immediately starts counting when the input
X006 turns ON.
The up-count input is X000, and the down-count input is X001.
• A high speed counter can be reset by X011 in a sequence as shown
in the figure, but C249 is immediately reset without any program
when X002 is closed. So a program with X011 is not necessary.
• The up/down-count operation of C246 to C250 can be checked with
M8246 to M8250.
ON status: Down-counting
OFF status: Up-counting
3. 2-phase 2-count input
These counters are 32-bit binary bi-directional counters, and the operation of the output contact for the current value is
equivalent to that in 1-phase high speed counters described above.
• While X012 is ON, C251 counts the operation of the inputs X000 (A
phase) and X001 (B phase) as interrupt.
When X011 turns ON a RST instruction is executed and C251 is
reset.
• When the current value becomes equivalent to or larger than the set
value, Y002 turns ON. When the current value becomes equivalent
to or smaller than the set value, Y002 turns OFF.
• Y003 turns ON (for down-count) or OFF (for up-count) according to
the counting direction.
• When X006 turns ON while X012 is ON, C254 immediately starts
counting. Its counting inputs are X000 (A phase) and X001 (B
phase).
• In addition to reset by X011 in a sequence, C254 is reset
immediately when X002 turns ON.
• When the current value becomes equivalent to or larger than the set
value (D1, D0), Y004 turns ON. When the current value becomes
equivalent to or smaller than the set value, Y004 turns OFF.
• Y005 turns ON (for down-count) or OFF (for up-count) according to
the counting direction.
X011
X012
C249 K1234
RST C249
X011
X012
C246 D2(D3)
RST C246
Set value is (D3,D2)
X011
X012
C254 D0(D1)
RST C254
X011
X012
C251 K1234
RST C251
C251
Y002
Y003
C254
Y004
Y005
M8254
M8251