119
FX3G/FX3U/FX3UC Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
4 Devices in Detail
4.8 High Speed Counter [C] (FX3G PLCs)
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
2. Devices used to check the counting direction of 1-phase 2-count input counters and
2-phase 2-count input counters
3. Devices used to switch the high speed counter function
4.8.6 Assignment of counter input terminal and switching of function
When the counters C248, C253 and C254 are combined with the following special auxiliary relays, the allocation of the
input terminals and functions are changed.
In a program, put a special auxiliary relay just before a target counter.
Type Counter No. Monitoring device OFF ON
1-phase
2-counting input
C246 M8246
Up-counting Down-counting
C247 M8247
C248 M8248
C249 M8249
C250 M8250
2-phase
2-counting input
C251 M8251
C252 M8252
C253 M8253
C254 M8254
C255 M8255
Device No. Name Description
M8388
Contact for changing function of
high speed counter
Changes the function of high speed counter.
M8392
Function switching
device
Switches the function of C248 and C253.
(For details, refer to Subsection 4.8.6.)
M8395 Switches the function of C254. (For details, refer to Subsection 4.8.6.)
Counter No.
When using assignment of counter input terminal and
switching of function
Description
C248(OP) • Reset input is not provided.
C253(OP) • Reset input is not provided.
C254(OP)
• The input count (2-phase 2-count) changes
as follows:
Phase A: Changes from X000 to X006.
Phase B: Changes from X001 to X007.
• Reset input is not provided.
• Start input is not provided.
M8388
M8392
C248
K
M8388
M8392
C253
K
M8388
M8395
C254
K