Function description
Operating Manual PSSu E S 2AI RTD(-T)
22017-EN-07
15
}
Start the PSSuniversal system. Measurement of the line resistance will start.
– The measurement will be more accurate if the line temperature is the same during
measurement as it is during operation.
}
In the system's PII (system environment A) or in the I/O data element "Data" (system
environment B), the measurement value appears as a hexadecimal value. Convert this
value into a decimal figure and note down the decimal value. This decimal value is the
measuring line resistance in 1/16 Ohm.
To account for the line resistance within the configuration, follow the instructions below:
}
Call up the module configuration in the system software.
}
Enter the measuring line resistance (feed and return line) in 1/16 Ohm under "2-wire
measurement offset".
– When you have established the measuring line resistance using the module, re-se-
lect the required sensor under "Measuring range".
4.3.5
Digital filter
A digital filter suppresses interference frequencies in the input signals. The module's pro-
cessing time will vary depending on the filter. With 3-wire measurement, or when a sensor
with four wires is connected, the filter time is double that found with a 2-wire measurement.
The module's processing time corresponds approximately to the sum of the filter times of
both inputs.
You can select one of the following filters per input:
Filtered
frequencies
Attenuation
Filter time per input
2-wire measurement
Filter time per input
3-wire measurement
4-wire sensor connection
60 Hz
90 dB
103 ms
206 ms
50 Hz
80 dB
122 ms
244 ms
50 Hz and 60
Hz
65 dB
122 ms
244 ms
50 Hz and 60
Hz
69 dB
202 ms
404 ms
50 Hz and 60
Hz
74 dB
482 ms
964 ms
