Nitrate ion concn. measuring probe - has temp. sensor for temp. compensation of probe output signal

摘要

A device for measuring nitrate ion concns. in solns. or suspensions consists of a single probe with a nitrate-selective contact membrane module, a ceramic diaphragm, an internal electrolyte and a silver/silver chloride reference system for connection to an evaluation unit. The novelty comprises the provision, near the contact membrane module (2,3), of a temp. sensor (1) providing an output which can be combined, for temp. compensation purposes, with the probe output in a microprocessor of the evaluation unit. The contact membrane module (2) is pref. exchangeable, e.g., screwed to the probe housing tube (16). The temp. sensor (1) is pref. a low thermal capacity, semiconductor element, e.g., a thermistor. USE/ADVANTAGE - The device forms a mobile measuring system for use in agriculture, forestry, water management and environmental protection. Temp. compensation is provided without preventing `field use' of the device.