Frequently Asked Questions:
RTD Sensors

An RTD (Resistance Temperature Detector) measures temperature by correlating resistance with temperature. Specifically, Tel-Tru uses high-quality Platinum RTD sensors (Pt100 or Pt1000), which are highly stable and known for superior accuracy and reliability across wide industrial temperature ranges.

Industrial processes often demand high accuracy, typically requiring Class A or better. Tel-Tru RTDs are designed for precision, often available in highly accurate configurations such as 1/3 or 1/10 DIN, making them suitable for demanding industrial or sanitary applications where measurement uncertainty must be minimized.

Yes, a thermowell is highly recommended and often required. It protects the delicate RTD sensor from damaging process conditions like high pressure, corrosive fluids, or high velocity, and allows for the replacement or maintenance of the RTD without shutting down or draining the process line.

The number of wires relates to compensation for lead wire resistance. 3-wire and 4-wire RTDs are the industry standard for industrial applications because they provide automatic compensation, virtually eliminating errors from the lead length and ensuring the highest measurement accuracy. We recommend 3- or 4-wire RTDs for any critical application.

Yes. Tel-Tru offers RTD thermometer probe assemblies with integrated compact transmitters designed specifically for precision temperature measurement in demanding sanitary and industrial environments. This simplifies installation and provides a standardized 4-20mA output for PLC or DCS integration.