Page 55
Setting Sensor Parameters
optoNCDT 1900 / EtherCAT
i
The defined type of average value and the averaging number must be stored in the sensor so that they are retained after switch-
ing off.
Averaging has no effect on the measuring rate or data rate in case of digital measurement value output. The averaging numbers can
also be programmed via the digital interfaces. The optoNCDT 1900-IE sensor is delivered with “Median 9” as factory settings, i.e.
median averaging over 9 measurement values.
Depending on the type of average and the number of averaged values, different transition response times result thereof, see Chap.
.
7.5.2.2
Moving Average
The definable number N for successive measurements (window width) is used to calculate the arithmetic average M
mov
according to
the following formula:
MV
(
k
)
k
=1
N
N
M
=
mov
MV
Measurement value,
N
Averaging number,
k
Running index
M
mov
Averaging value or output value
Method:
Each new measured value is added, the first (oldest) measured value is removed from the averaging (from the window) again. In this
way, it is possible to achieve short transition response times with measured value jumps.
Example: N = 4
... 0, 1, 2, 2, 1, 3
2, 2, 1, 3
4
=
M
(
n
)
mov
... 1, 2, 2, 1, 3, 4
2, 1, 3, 4
4
=
M
(
n+1
)
mov
Measurement values
Output value
Note:
For the moving averaging in the optoNCDT 1900-IE, only powers of 2 are permitted for the averaging number
N
. Range of values for
the averaging number
N
is 1 / 2 / 4 / 8 ... 4096.
Summary of Contents for ILD1900-10
Page 8: ...optoNCDT 1900 EtherCAT ...
Page 110: ...Page 110 Appendix EtherCAT Documentation optoNCDT 1900 EtherCAT ...
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