Servomex SERVOPRO FID, Руководство оператора

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SERVOPRO FID Online Total Hydrocarbons Analyser
SERVOPRO FID 01000001A rev:5 33
4.8.2 Filter
The filter menu allows configuring filtering algorithms that are used to filter FID
signal.
Figure 22 – Filter menu
4.8.2.1 Averaging number
The measurement can be filtered using a moving average. The moving average
principle is very simple. For example, a moving average of 10 readings is the sum
of previous 10 readings divided by 10. If readings are R
M
, R
M-1
,…,R
M-9
, the
formula is:
10
...
9 1
− −
+ + +
=
M M M
R R R
result
The range of this value is between 1 and 30.
4.8.2.2 Averaging edge
The averaging edge is used to reset the moving average. The unit of this value is
the same as the process. For example, if this value is configured to 1, the moving
average will be reset if the reading, without filtering, increases by 1.
This is used to reset the filter when a fluctuation occurs in the reading. This
increases the response time of the filter.
The range of this value is between 0 and fullscale.
4.8.2.3 Median number
The median number is used to perform a median filter on the measurement. The
median is performed before the moving average filter.
For example, a median filter of 10 readings is the median of previous 10 readings.
If readings are R
M
, R
M-1
,…,R
M-9
, the formula is:
Result = median[R
M
, R
M-1
,…,R
M-9
]
The range of this value is between 0 and 10.
<-- <<<HIDDEN 2: Filter>>>
1) Averaging number: 30
2) Averaging edge: 0.5
3) Median number: 5