Inputs
Analog Input Sensors
Temperature Sensors Flow sensors Humidity sensors Potentiometers Pressure Sensors
Tank Levels Load Calls Light Sensors Speed and position sensors
PT100 Inputs Using the extension module It can be connected with one two-wire or three-wire Resistance Temperature Detector (RTD) PT100. The RTD sensor is comprised of a resistor that changes value with temperature. The most common RTD by far is the PT100 385. This element measures 100 Ohms @ 0 degrees C (32 °F) and 138.5 Ohms @ 100 °C (212.0 °F). The temperature range for a PT100 inputs is within -50 to 200 °C (resolution 0.3 °C).
Using a two-wire connection the unit can not compensate error/ tolerance caused by the resistance in measurement loop. The measurement error of 1Ω is equivalent to an error of 2.5 °C. The three-wire technology can inhibit the influence of measurement results caused by cable length (ohmic resistance).
Three-wire connection
MIRCO PLC PT100 Inputs
Two-wire connection
MIRCO PLC PT100 Inputs
Compensator
Compensator
Input “+”
Input “+”
RTD PT100
RTD PT100
A
ADC
A
ADC
Input “-”
Input “-”
A - Ampli er; ADC - Analog-to-Digital Converter
A - Ampli er; ADC - Analog-to-Digital Converter
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