Temperature Transmitters

What is a Temperature Transmitter?

A temperature transmitter, also known as pt100 transmitter, thermocouple transmitter or RTD transmitter, is a device that connects to a temperature sensor (thermocouple or RTD) and transmits the signal to another location for monitoring or process control applications. Temperature transmitters isolate, amplify, filter EMC noise, linearize, and convert the input signal from the sensor into a usable 4-20mA output. The 4-20mA output is effective as the temperature sensors generally produce weak signals, therefore, Temperature Transmitters function as an amplifier which can interface with industrial measuring equipment such as PLCs or data loggers.

There are available in many forms which vary in degrees of sophistication ranging from compact DIN rail mounted units to programmable smart devices. RS Components offer a wide range of accurate, high-performance transmitters from leading brands including PR Electronics, Jumo, LKMelectronic and of course RS PRO.

What are the different types of temperature transmitter?

Transmitters come in a range of types and mounting methods. Some of the most common are:

Head-Mounted temperature transmitters incorporate the transmitter into a connection head or housing of the sensor. Simple in design they are relatively easy to install and require minimal wiring and set up.
Field Mount temperature transmitters are designed to operate in harsh environments. They are typically housed in robust enclosures for extra protection from the elements.
Rail Mount temperature transmitters are designed to be mounted on DIN rails and can be grouped together in a panel for easy access.
Explosion-proof temperature transmitters are high-precision transmitters and are used in hazardous areas. They must only be used by qualified engineers and technicians. They can be DIN rail or head mounting comes with ATEX and or IECEx certifications.

How does a temperature transmitter work?

The transmitter works by drawing the current from a remote DC power supply which is connected to the sensor input. Connecting the transmitter output signal, remote power supply and process equipment in a circuit only requires 2 copper wires as the signal and power supply line work as a dual function.

The two-wire transmission allows the transmitter to be mounted near the sensor in a remote setting to lessen the effects of signal degradation from sensors with a low level of output

Applications of Temperature Transmitters:

Common applications include: