How to distinguish PT100 thermal resistance and thermocouple probe
2, two kinds of sensors to detect temperature range, thermal resistance test 0 - in general The temperature range of 150 degrees ( Of course can detect negative temperature) , can detect 0 - thermocouple Temperature range of 1000 c ( Even higher) So, the former is low temperature detection, which is high temperature detection.
the third, from the material, thermal resistance is a kind of metal material and temperature sensitive change of metal materials, thermocouple is bimetallic material, both of two different metals, due to the changes of temperature, in two different electric potential difference at both ends of the wire.
4, in the work site judgment
thermocouple is negative, compensation conductor is divided into positive and negative, connection, first configure it. In the run. Common have short circuit, open circuit, poor contact ( A multimeter can judge) And metamorphism ( According to the surface color to identify) 。 Checks, to make a thermocouple is separated from the secondary table with tools short compensation line in the second table, table indicating at room temperature and sub thermocouple terminals, thermocouple in the ambient temperature (table batch No, compensation wire fault) That measure roughly with a multimeter mv file thermocouple thermoelectric potential ( Such as normal, please check the process) 。
thermal resistance short circuit and open circuit with a multimeter can determine, in the running, doubt short circuit, as long as the end resistance will be removed a thread to see display instrument, such as, thermal resistance, short circuit back to zero wire short circuit, ensure the normal connection and configuration, the table values showed low or instability, possibility of protecting tube water show, the largest thermal resistance circuit according to the minimum short circuit.