NMT81

The operating principle of Resistance Temperature Detectors (RTDs) is based on the property that the resistance of metallic conductors varies with temperature. The core mechanism is as follows: when temperature changes, the amplitude of lattice vibration in metallic conductors such as platinum and copper alters, which creates varying degrees of obstruction to electron movement, and consequently changes the resistance value. Take the Pt100 platinum RTD as an example. Its standard resistance is 100 Ω at 0 °C. The resistance increases by approximately 0.385 Ω for every 1 °C rise in temperature, showing a high‑linearity 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 connection is adopted to eliminate lead‑wire errors. Finally, resistance values are converted into temperature values according to international standard conversion tables.

Prothermo NMT81 is used for medium average temperature measurement, with an optional level monitoring function. The device incorporates a 2‑meter capacitive sensor to continuously measure level height and output current level information at any time. As a high‑precision average temperature gauge, the NMT81 is designed for use with tank gauging instruments (e.g. servo level gauges Proservo NMS80, NMS81 and NMS83; radar level gauges Micropilot NMR81 and NMR84; tank‑side indicator NRF81). It is the ideal solution for custody transfer and inventory monitoring applications.