IP3202-Bxxx, IE3202 Signal Connection
4 Channel Analog Input PT100 (RTD)
The advantage of four-wire technique is that the error resulting from the cable and contacts is included in the measurement and cancelled out. In the 3-wire technique, the conductor resistance to the resistance sensor is measured in one direction only, and is multiplied by two. This requires the outward and return lines to have approximately the same ohmic resistance. An error is present in the two-wire technique; temperature differences and cable cross-sections can make this error vary considerably.
The connection type, 2-, 3- or 4-wire has to be the same for all four channels!
Pin 5 (shield) is capacitatively coupled to the chassis of your Fieldbus Box.
Supply voltage
US - supplies the electronics for the fieldbus and for the sensor. It is electrically isolated from UP.
UP - Is not required for the function of the module, and does not have to be fed in.
If you use UP to pass the power on, and you connect a module in which US and UP are not electrically isolated (e.g. any digital module) then the electrical isolation is removed by the downstream connection.
LED indicators - meanings
There is a green Run LED and a red Error LED for each channel.
The Run LED illuminates when data is being transferred to the D/A
converter. The red Error LED indicates that there is an error
(broken conductor, measured value outside the range, temperature
compensation outside the valid range).
The device is functioning correctly if the Run LED is lit and the
Error LED is unlit.
