Parameters Of The Channel Pairs - Siemens SIMATIC ET 200SP HA Equipment Manual

5.2.4

Parameters of the channel pairs

Sensor evaluation
You select the type of sensor evaluation with the "Sensor evaluation" parameter:
• 1oo1 evaluation
With 1oo1 evaluation one sensor is connected.
The sensor occupies one input channel.
• 1oo2 evaluation, equivalent/non-equivalent
With 1oo2 evaluation equivalent/non-equivalent, two input channels are occupied by one of
the following:
– A two-channel, equivalent/non-equivalent sensor
– Two single-channel sensors
The input signals are compared internally for equivalence or non-equivalence.
Note that in 1oo2 evaluation, two channels are grouped into a channel pair. The number of
available process signals of the F-module is reduced accordingly.
The evaluation result for the channel pair is available at the input of the channel with the low
channel number (channel "n").
Dependencies:
• If the "1oo2 evaluation, equivalent" or "1oo2 evaluation, non-equivalent" option is selected
for the "Sensor evaluation" parameter, the "Input delay (ms)" of a channel must be less than
the configured "Discrepancy time (ms)".
Discrepancy analysis:
If you are using a two-channel sensor or two single-channel sensors that measure the same
process variable, the response of the sensors will be delayed relative to one another due to the
limited precision of their arrangement, for example.
The discrepancy analysis for equivalence/non-equivalence is used for fail-safe inputs to detect
errors from the time sequence of two signals of the same functionality. The discrepancy analysis
is started when different levels are detected for two associated input signals (when testing for
non-equivalence: the same level). On expiration of a configurable time interval, i.e. the so-called
discrepancy time, a check is made to determine whether the difference in the signal levels has
disappeared (when testing for non-equivalence: the equivalence of the signal levels). If not,
there is a discrepancy error.
Sensor supply for 1oo2
You use this parameter to select the sensor supplies for 1oo2 evaluation:
• Each sensor has its own sensor supply
• Both sensors on one sensor supply
In this setting, the sensor supply of the channel with the low channel number (channel "n")
is used, for example, the sensor supply of channel "0" is used for channel pair 0/8.
F-DI 16x24VDC HA
Equipment Manual, 08/2021, A5E45647528-AD
Parameters/address space
5.2 Description of parameters
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