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3 SPECIFICATION
3.4.1 Sampling processing
3.4.2 Moving average processing
The A/D conversion is performed successively for the analog input, and the converted
digital output values are stored in the remote register.
The processing time to store the digital output value into the remote register after the
sampling processing differs depending on the number of A/D conversion enabled
channels.
(Processing time)
Number of A/D conversion enabled channels) 1 (ms)
[Example] When three channels, channels 1, 2, and 3 are enabled for conversion:
3×1 = 3 (ms)
The specified count of digital output values imported per sampling time are averaged to
find a value, which is then stored into the remote register.
Since average processing is performed with data shifted per sampling, the most recent
digital output value is available.
Average processing can be performed without changing the conversion speed.
Use moving average processing count setting (address RWwm+2) to set the number
of moving average processings.
The count can be selected from among four types: 4, 8, 16 and 32 times.
Moving average processing at the count setting of 4 times
A/D conversion value
4000
1
2000
0
Data transition inside remote register
Stored first time
+
2
1
Sampling time
3
4
2
5
6
8
7
A/D conversion completion flag ON
Stored second time
+
+
+
+
+
3
4
2
3
4
5
4
4
3 - 9
MELSEC-A
Maximum conversion speed
9
12
10
11
Remote register
Stored first time
Stored second time
Digital output value
Stored third time
Time [ms]
Stored third time
+
+
+
3
4
5
6
4