No announcement yet.

Measurement Principle NTC sensing


  • Measurement Principle NTC sensing

    This article gives an introduction into the temperature measurement by NTC Sensors.
    Click image for larger version  Name:	NTC.png Views:	0 Size:	59.4 KB ID:	651

    Measurement principle
    A NTC Sensor is a temperature sensitive resistance with a Negativ Temperature Coefficient (NTC). Therefore, the resistance of the sensor can be measured and converted into the corresponding temperature value. The higher the temperature, the lower the sensors resistance.
    NTC and PTC characteristic curve
    Click image for larger version  Name:	NTC_sensor_characteristic_curve.png Views:	0 Size:	9.6 KB ID:	656
    RMS Devices
    Rotronic offers two Minilogger based on NTC sensing.
    • RMS-MLOG-T-868/915 -> fix internal NTC sensor
    • RMS-MLOG-T10-868/915 -> external NTC sensor connectable
    Click image for larger version  Name:	MLOG_NTC.png Views:	0 Size:	42.9 KB ID:	655

    NTC sensors
    Rotronic also offers various types of NTC sensors for several ranges and applications for the Minilogger.

    NTC Sensor Parameters
    • B is a sensor material specific constant and stands for the electrical conductivity. As higher B as more isolating the material is.
    • R25 – Nominal resistance of the sensor at 25°C – also a material specific constant.
    If the application requires the use of a different sensor than listed above, both parameters of the sensor need to be read out from the datasheet and be edited into the device properties of the Minilogger.
    Ranges and Parameters:

    Advantages of NTC
    • Robustness of the sensor
    • Wide range / extreme temperatures possible to measure
    • Lower price than a Platinum sensor PT (e. g. PT100)

    Disadvantage of NTC
    • Less accuracy than a PT sensor
    • Bigger measurement deviation between identical sensor types. A higher tolerance range needs to be considered e. g. for Alarming.

    The measurement accuracy consists of the electronical accuracy of the Minilogger and the accuracy of the sensor.If the application requires the use of a different sensor than listed above, the accuracy of the desired sensor (see the relevant datasheet) is to be considered.
      Posting comments is disabled.

    Latest Articles