Mitsubishi Q64AD, User Manual

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MELSEC-Q
3 SPECIFICATIONS
(a) When averaging processing is specified for the set amount of time
1) The number of processing repetitions within the set time differs
according to the number of channels used (number of channels for
which A/D conversion is enabled) and whether or not temperature-drift
compensation is used.
• Without the temperature drift compensation function
(Set time) 1000 (Number of
processing repetitions)
=
(Number of channels used) 80 ( s/1 channel)
• With the temperature drift compensation function
(Set time) 1000
(Number of
processing repetitions)
=
(Number of channels used) 80 ( s/1 channel) + 160
[Example]
When averaging processing is performed with four channels (channels 1, 2,
3, and 4) for the set time of 50 ms with the temperature drift compensation
function on, measurement is performed 104 times and the average value is
output.
50 1000
(4 80) + 160
= 104.17 (times) …… Round down the number.
2) When 7 or 8 channels are used with the temperature drift compensation
function on, set the average time to 3 ms or more.
If the time is set to 2 ms or less, the average number of times becomes
less than 3 and it causes the digital output value to become 0 since a
sum excluding the maximum and minimum values will be averaged.
(b) When the averaging processing is specified for the set number of times
The time required to store the average value calculated using the average
number of times in the buffer memory differs according to the number of
channels used (the number of channels set to A/D conversion enable) and
whether or not the temperature drift compensation is used.
1) Without the temperature drift compensation function
(Processing time) = (Set number of times)
{(Number of channels used) 80}/1000
(Unit: ms)
2) With the temperature drift compensation function
(Processing time) = (Set number of times)
[{(Number of channels used) 80} + 160]/1000
(Unit: ms)
[Example]
When averaging processing is performed with four channels (1, 2, 3 and 4)
for the set number of 100 times with temperature-drift compensation on, an
average value is output every 48 ms.
100 {(4 80) + 160} ÷ 1000 = 48 (ms)