Sensors

Resistance temperature detectors (RTD’s) use the change in the electrical resistance of a wire wound device with a positive temperature coefficient to signal a change in the temperature. As a standard, Hotset uses 100-ohm class B platinum wire-wound elements manufactured to the DIN EN60751 standard (formerly IEC 751). While more expensive, RTDs offer more accurate linear readings than thermocouples. However they have longer response times, are not “tip sensitive”, and are more subject to damage from vibration.

 

RTDs, Resistance Temperature Detectors, primarily utilize platinum (alternatively nickel or other materials).  For applications under 600 degrees Celsius, RTDs are utilized in as a external sensor to precisely control a heater.

Thermocouples are fabricated by joining together two electrical conductors, each made of different metal alloys. This junction generates a small millivolt signal that changes with temperature. The signal is sent to an electronic device, which is used to display and/or control the temperature. The most common calibrations for thermocouples are types J, K, and T.