NMT532

The operating principle of Resistance Temperature Detectors (RTDs) is based on the characteristic that the resistance of metallic conductors varies with temperature for temperature measurement. Its core principle: as temperature changes, the amplitude of lattice vibration of metallic conductors such as platinum and copper alters, which changes the degree of obstruction to electron movement, and consequently the resistance value varies. Take the Pt100 platinum RTD as an example. Its standard resistance is 100 Ω at 0 ℃. The resistance increases by approximately 0.385 Ω for every 1 ℃ rise in temperature, showing a highly linear relationship within a certain temperature range. In practical measurement, a constant‑current source or bridge circuit converts resistance variation into electrical signals. Three‑wire / four‑wire wiring is adopted to eliminate lead‑wire errors. Finally, resistance values are converted into temperature values according to international standard calibration tables.

Prothermo NMT532 intrinsically‑safe multi‑signal converter equipped with high‑precision average temperature sensor. Designed for inventory control, it is an ideal solution for various tank‑gauging applications and delivers stable average temperature data via HART communication. For custody transfer and accurate inventory measurement, it is recommended to use the Proservo NMS5 or the tank‑side indicator NRF590 paired with Micropilot radar level transmitters.