ICP DAS USA ET-7000 Series User Manual page 143

Appendix D: Modbus Application Notes


Moving average value of one AI channel
AI
The average value of each AI can be reached on a regular interval when the moving average
function is enabled.
For example, a five-item simple moving average would be the sum of the reading value of the
five most recent reading value, divided by five; a 20-item moving average would be the sum
of the 20 most recent reading value divided by 20, and so on. Each item the most recent
reading value is added to the equation and the most distant item is dropped off.
Register
00347
40059
Address 30144 to 30153 recodes the average value of each AI channel.
ET-7017 AI Average value of one channel Table
Channel Number
AI0
AI1
ET-7000 AIO User Manual, Apr. 2009, V1.04, EMH-011-104
V
V
n-4
n-5
V
n-6
T T T
n-6 n-5 n-4
V =(V +V
Ave_n n n-1
Enable the moving value of the AI channels
0=disabled
1=enabled
(Default=0)
Average times for each AI channel
0 ~ 40
Register
30144 0 ~65535 or –32768 ~ +32767
30145 0 ~65535 or –32768 ~ +32767
V
V
n-3
n-2
T T
n-3 n-2
+V +V +...+V
n-1 n-3 n-6
Description
V
n
V
n-1
T T
n-1 n
) / 7
(7: 7 records)
Description
----------
143
Time