Mitsubishi Electric MELSEC-Q Structured Programming Manual page 229

FXCPU Structured Programming Manual
[Device & Common]
6. FX /FX PLCs
0S 0
Inputs X000 to X007 have a digital filter circuit of 0 to 15 ms respectively. The digital filter constant is
determined by the value in the range from 0 to 15 stored in the special data register D8020.
D8020 is automatically set to "10 (ms)" when the PLC is powered ON from OFF.
X010 to X017 function in the same way as X00 to X07, but their digital filter constant is determined by the
value stored in the special data register D8021.
Input terminal Filter
X000 0ms
1ms
10ms
X007
15ms
Input terminal Filter
X010 0ms
1ms
10ms
X017
15ms
1) Program example for adjusting the input filter
When the program shown below is executed, the filter constant is changed to "0 ms".
Because the C-R filter is provided in the hardware, however, the filter constant actually becomes the
value shown in the table below when "0" is specified.
M8000
RUN monitor
Input number
X000 to X005
X006 to X017
• The input filter value can be changed as many times as needed in the middle of a program.
• The input filter adjustment described here is not necessary when high speed counters, input interrupts or
pulse catch relays (M8056 to M8059) are used.
4.2 Supplement of Special Devices (M8000 and later and D8000 and later)
0
1
Determined by the value stored in D8020 (Initial value: 10).
10
Input refresh
Image
15
memory
0
1
Determined by the value stored in D8021 (Initial value: 10).
10
Input refresh
Image
15
memory
MOV
EN ENO
s d
K0 D8020
Input filter value when "0" is set
50μs
200μs
4 Operations of Special Devices (M8000 and later, D8000 and later)
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2
3
4
5
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