Pt 100 sensor

Pt 100 sensors are the most common type of platinum resistance thermometers. A Pt 100 sensor is a temperature sensor which works by measuring electrical resistance through platinum (Pt) metal and can measure temperatures up to 600 °C.

The resistance in the metal increases as temperature rises. The resistance at 0 °C is 100 ohms – hence the name Pt 100. PT 500 and Pt 1000 sensors with corresponding resistance at 0 °C are also available. Therefore, the PT 100 sensor can also be used for reading temperature.

More precise

The sensor measures more precisely than other types of electrical-resistance sensors such as KTY and NTC, which use other metals, but is also more expensive. A Pt 100 sensor can measure temperatures up to 600 °C, where the others are limited to around 150 °C.

Three-wire sensors

Sensors that are connected with longer cable lengths may give imprecise readings, due to the cable’s inherent electrical resistance. This can be compensated for through the use of three-wire sensors, where the third wire measures resistance in the cable. However, this requires a regulator that can handle it.

Grundfos builds in or provides as an option Pt 100 sensors as a protection against overheating or too high temperature in pumps.