PT 1000

Resistance Temperature Detectors (RTDs) have a linear increase in resistance as temperature rises. RTDs come in 2-wire, 3-wire or 4-wire versions. A 2-wire RTD signal is affected by the distance to the controller. 3-wire or 4-wire RTDs can compensate for line losses.




Thermocouples have two dissimilar metal wires joined at the hot junction. As temperature changes, a millivolt signal is read at the cold junction. The most common types of temperature thermocouples are Type J thermocouples and Type K thermocouples. Advantages of thermocouple sensors include: low cost, small size, wider temperature ranges and faster response than RTDs. The disadvantages of using thermocouples include: they are less linear and accurate than RTDs, a matching extension wire is ne

AutomationDirect offers a variety of industrial RTD probes and PT100 RTD sensors:




RTD Probes (with Connection Head)


RTD Probes (Spring-loaded with Connection Head)


RTD Probes (with Hex Nipple)


RTD Probes (Spring-loaded with Hex Nipple)


RTD Probes (with Attached Plug)


RTD Probes (with Lead Wire Transition)


New! ... RTD Sensors (Adjustable Immersion)


RTD Probes (M12 Cable Connection)


RTD Probes (Sanitary RTD Connection))


RTD Sensors (Bolt-on Ring)


New! ... Wall-mount RTD Sensors (Ambient Room Temperature Sensors)




For more RTD products, also see the Temperature Sensors & Transmitters section:


Temperature Transmitters (RTD Input)


Programmable Temperature Transmitters (T/C or RTD Input)


Temperature Transmitters (Integral Sensor)