Table of Contents
Advertisement
X20(c)CP1301, X20CP1381 and X20CP1382
16.3.2.3 Input filter
The analog inputs are equipped with a configurable input filter.
16.3.2.3.1 Input ramp limitation
Input ramp limitation can only take place when a filter is used; the input ramp is limited before filtering takes place.
The amount the input value changes is checked to make sure that specified limits are not exceeded. If the values
are exceeded, the adjusted input value is equal to the old value ± the limit value.
Configurable limit values:
Value
0
1
2
3
4
5
6
7
Input ramp limitation is well suited for suppressing disturbances (spikes). The following examples show the function
of the input ramp limitation based on an input jump and a disturbance.
Example 1
The input value jumps from 8000 to 17000. The diagram shows the adjusted input value with the following settings:
Input ramp limitation = 4 = 0x07FF = 2047
Filter level = 2
17000
8000
36
Limit value
The input value is used without limitation.
0x3FFF = 16383
0x1FFF = 8191
0x0FFF = 4095
0x07FF = 2047
0x03FF = 1023
0x01FF = 511
0x00FF = 255
Input value
Internal adjusted input value before the filter
0
1
2
3
Input jump
Figure 25: Tracked input value for input jump
4
5
6
7
8
t [ms]
Data sheet V1.21
Advertisement
Table of Contents
