FX
/FX
/FX
Series Programmable Controllers
3G
3U
3UC
Programming Manual - Basic & Applied Instruction Edition
2)
When special analog adapters and FX
Counter type
Software
counter
C241,
C242,
C235, C236,
C243,
C237, C238,
1-phase
C244,
C239, C240
1-counting input
C245
C244(OP),
−
C245(OP)
C247,
C246,
1-phase
C248,
2-counting input
C248(OP)
C249, C250
1 edge
2-
count
C252,
phase
C253(OP),
2-
C251, C253
count-
C254,
4 edge
ing
count
C255
input
*1.
When an index register is added to a counter number specified by a HSCS, HSCR, HSZ or HSCT instruction,
all hardware counters are switched to software counters.
*2.
The high-speed counters C244 (OP) and C245 (OP) can count up to 10 kHz.
3. Calculation of the total frequency
Total frequency ≥ Sum of "Response frequency of high-speed counter ×
Magnification for calculating total frequency"
4. Calculation example
When only HSZ instruction is used 6 times in a program, the total frequency and response frequency are calculated as
follows in accordance with the columns for "When only HSZ instruction is used" shown above.
This calculation example is provided for a system configuration not including special analog adapters and FX
Series special function blocks/units.
Used high-speed counter No.
C237
C241
C253(OP)
[4 edge count]
1) The total frequency is calculated as follows because HSZ instruction is used 6 times:
Total frequency
2) The sum of the response frequencies of the high-speed counters
being used is calculated as follows:
"30 kHz × 1[C237]" + "20 kHz × 1[C241]" + "4kHz × 4[C253(OP)]" = 66 kHz ≤ 71 kHz
114
When HSZ and HSCT
Magnifica-
Following
instructions are not
tion for
software
calculating
counter with
total
Maximum
HSCS, HSCR,
frequency
response
HSZ or HSCT
frequency
instruction
*1
(kHz)
×1
30
×1
10
×1
30
×1
30
×4
7.5
frequency
Operates as
software counter
Software counter
= 80 − 1.5 × 6 = 71 kHz
/FX
Series special function blocks/units are used
3U
3UC
Response frequency and total frequency according to instruction use condition
When only HSCT
instruction is used
used
Maximum
Total
Total
response
frequency
frequency
frequency
(kHz)
(kHz)
(kHz)
25
10
60
25
25
6.2
Input
Maximum response frequency
calculation
40 − 6 (times) = 34 kHz
30 kHz
40 − 6(times) = 34 kHz
20 kHz
{40 − 6(times)} ÷ 4 = 8.5 kHz
4 kHz
4.7 High-Speed Counter [C] (FX3U/FX3UC PLC)
When only HSZ
instruction is used
Maximum
Total
response
frequency
frequency
(kHz)
(kHz)
30 - (Num-
ber of
50−
instruc-
1.5×(Num
*2
tion)
50
ber of
instruc-
tion)
(30-Num-
ber of
instruc-
tion) ÷ 4
Magnification for
calculating total
frequency
× 1
× 1
× 4
4 Devices in Detail
When both HSZ and HSCT
instructions are used
Maximum
Total
response
frequency
frequency
(kHz)
(kHz)
25-(Number
of instruc-
50−
*2
tion)
1.5×(Num
ber of
instruc-
tion)
(25-Number
of instruc-
tion) ÷ 4
/FX
3U
3UC
Used
instruction
HSZ
instruction × 6
times