Temperature measuring transducers

They are devices that connect to a temperature sensor to send a signal elsewhere for regulation, monitoring and control purposes. Typically, the temperature sensor is an RTD or TC (thermocouple) sensor.
The main purpose of the converter is to prepare the analogue measurement signal from the sensors for transport over longer distances without degrading the accuracy of the measurement. The role of the temperature transmitter can also be to galvanically isolate the temperature signal, which is particularly important for thermocouple and high temperature measurements. EMC interference is filtered, amplified and the temperature sensor signal is converted to the 4-20 mA or 0-10 V DC range for further use.
4-20 mA temperature transmitters are common in industrial manufacturing, as most industrial equipment communicates over this standardised signal range. The transmitted temperature signal can be varied within the temperature transmitter to suit the needs of the application. For example, 4 mA can be used to represent 0 °C and the highest value in the range (20 mA) can be used to represent 100 °C.
Temperature transducers convert a thermocouple or RTD signal to a 4-20 mA output signal. This is the ideal solution for many remote temperature measurement applications. Conventional temperature sensing devices such as thermocouples and RTDs emit very small “signals”. These sensors are connected to a two-wire transducer that will amplify the small measurement signal. Once set to a usable level, this signal can be transmitted over ordinary copper wire and used to drive other equipment. This equipment includes controllers, meters, data loggers, graph recorders, computers or controllers.
The temperature transmitter draws current from a remote DC supply in proportion to the sensor input. The actual signal is transmitted as a change in the supply current. Specifically, a transducer with a thermocouple input will draw 4 mA of current from the DC supply when measuring the minimum process temperature. Then, as the temperature rises, the converter will pump proportionally more current until it reaches 20 mA. This 20 mA signal corresponds to the maximum sensible temperature of the thermocouple. Physically, only two copper wires are needed to connect the output signal of the temperature transmitter in the circuit to the remote power supply and the process equipment. This is possible because the signal and the power line are combined (one circuit has dual function).
INOR offers a complete range of temperature transmitters, including ATEX and SIL2 certified, with HART, PROFIBUS and NFC communication.