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RAD-900-...
PHOENIX CONTACT
3827_en_B
3.2
RAD-PT100-4-IFS - extension module with four
temperature inputs
The analog RAD-PT100-4-IFS I/O extension module has four Pt 100 inputs for
temperatures between -50°C ... +250°C. The Pt 100 inputs T1 ... T4 can be mapped to the
analog outputs I1/U1 ... I4/U4 of the RAD-AO4-IFS extension module. All the inputs are
electrically isolated from one another, from the supply voltage, and from the remaining
electronics.
Pt 100 resistance thermometers can be connected to the RAD-PT100-4-IFS I/O extension
module. The thermometers change their resistance depending on the temperature. The
Pt 100 input signals are acquired by the RAD-PT100-4-IFS and can be mapped to
proportional, analog voltage or current signals of the RAD-AO4-IFS output module.
Example: At the Pt 100 input, a current of 0 mA or a voltage of 0 V is released at the output
module at a temperature of -50°C. At the Pt 100 input, a current of 20 mA or a voltage of 10 V
is released at the output at a temperature of 250°C.
3.2.1
Connecting sensors
You can connect 2-wire or 3-wire sensors to the extension module. Observe the measuring
errors depending on the different measuring methods.
2-wire connection technology
2-wire connection technology is the most cost-effective connection method. The
temperature-related voltage is not directly measured at the sensor and therefore falsified by
the two cable resistances R
L
. The measuring errors that occur may lead to the entire
measurement to become useless. Please observe the diagrams in Section “Measuring
errors using 2-wire connection technology” on page 22.
With 2-wire technology, you need an insertion bridge between terminals x.2 and x.3.
Use the I/O extension modules in connection with the RAD-900-... wireless module,
firmware version 1.40 or later. You can update the firmware free of charge using the
PSI-CONF software, Version 2.04 or later.
The firmware and software can be found on the Internet at
Pt 100 input
Analog output
-50°C
0 mA or 0 V
+250°C
20 mA or 10 V