Mitsubishi FX2-16E series, Руководство пользователя

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220
FX
3U
Series Programmable Controllers
User’s Manual - Hardware Edition
11 Use of High-speed Counters (C235 to C255)
11.9 Calculation of Response Frequency and Overall Frequency
1) Calculation of overall frequency
The overall frequency is calculated by the high-speed comparison instruction used in the program based
on the above table.
Overall frequency
≥
Sum of "response frequency of high-speed counter
×
Magnification for
calculation of overall frequency"
2) Example of calculation
When only HSZ instruction is used six times in a program, the frequency is calculated by the formulas
shown in the "Only HSZ instruction" column in the above table.
High-speed counter No. to be
used
Input
frequency
Calculation of max.
response frequency
Magnification
for
calculation of
overall
frequency
Instruction
to be used
C237
Operation as
software counter
20kHz 30 - 6(times) = 24kHz
×
1
HSZ instruc-
tion is used
six times.
C241
Software counter
10kHz 30 - 6(times) = 24kHz
×
1
C253(OP)
[
4 edge count
]
2kHz
{
30 - 6(times)
}
/ 4 = 6kHz
×
4
1) The overall frequency is calculated as shown below because HSZ instruction is used six times.
Overall frequency = 50 - 1.5
×
6 = 41kHz
2) The sum of the response frequencies of the high-speed counters used is
calculated as shown below.
"20kHz
×
1[C237]" + "10kHz
×
1[C241]" + "2kHz
×
4[C253(OP)]" = 38kHz
≤
41kHz