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Operation
optoNCDT 1402
Example: N = 4
... 0, 1, 2, 2, 1, 3
2, 2, 1, 3
4
= M (n)
gl
... 1, 2, 2, 1, 3, 4
2, 1, 3, 4
4
= M (n+1)
gl
Measurement values
Output
i
The moving average in the optoNCDT1402 can only be generated for up to a maximum of 128 values.
Median
6.3.3
The median is generated from a pre-selected number of measurement values. To do so, the incoming mea-
surement values (3, 5, 7 or 9 measurement values) are resorted again after every measurement. The average
value is then given as the median. In generating the median in the controller, 3, 5, 7 or 9 measurement values
are taken into account, i.e. there is never a median of 1. This permits individual interference pulses to be
repressed, but the measurement value curve is not smoothed to any great extent.
Example: Average from five measurement values
... 1 2 4 5 1 3 5
... 0 1 2 4 5 1 3
Sorted measurement values: 1 3 4 5 5
Sorted measurement values: 1 2 3 4 5
Median = 3
(n)
Median
= 4
(n+1)
Measurement Rate and Output Rate
6.4
The measurement rate defines the number of measurements performed by the sensor per second. The mea-
surement rate may be 1.5 kHz, 1.0 kHz, 750 Hz, 375 Hz or 50 Hz. Details of how to change the measurement
rate can be found in Chap. 8.3.13.
The output rate gives the actual number of measurement values at the sensor output per second. The maxi-
mum output rate can never exceed the measurement rate.
