Omron CJ1W-AD041-V1, Operation Manual

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Analog Input Functions and Operating Procedures Section 7-6
7-6-2 Conversion Time and Resolution Setting
Bits 08 to 15 in DM word m+18 can be used to set the conversion time and
resolution for the CJ1W-MAD42 to increase speed and accuracy.
This setting applies to analog inputs 1 to 4, i.e., there are not individual set-
tings for each input.
Note After making the DM settings from a Programming Device, it will be necessary
to either turn the power to the PLC OFF and ON, or turn ON the Special I/O
Unit Restart Bit in order to transfer the contents of the DM settings to the Spe-
cial I/O Unit.
7-6-3 Mean Value Processing
The Analog I/O Unit can compute the mean value of the conversion values of
analog inputs that have been previously sampled. Mean value processing
involves an operational mean value in the history buffers, so it has no effect on
the data refresh cycle. (The number of history buffers that can be set to use
mean value processing is 2, 4, 8, 16, 32, or 64.)
When “n” number of history buffers are being used, the first conversion data
will be stored for all “n” number of history buffers immediately after data con-
version has begun or after a disconnection is restored.
When mean value processing is used together with the peak value hold func-
tion, the mean value will be held.
To specify whether or not mean value processing is to be used, and to specify
the number of history buffers for mean data processing, use a Programming
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
Bit
D(m+18)
00: Conversion time = 1 ms, resolution = 4,000
C1: Conversion time = 250
µ
s, resolution = 8,000
(m = unit number x 100)
Conversion data Buffer 1
Buffer 2
Buffer 3
Buffer 4
Buffer n
(Mean value
processing)
Conversion value
(Values stored in
CIO words n+5 and
n+8)
(Discarded)