The ABB Conductivity Cell TB4042 expands the advancements in process conductivity measurement initiated by ABB with four-electrode conductivity measurement. Unlike four-electrode sensors, toroidal sensors have no electrodes.

The TB4042 Toroidal Conductivity Sensor provides a means for measuring solution conductivity in chemically aggressive solutions that corrode, foul, or otherwise destroy electrode type sensors.

The sensor itself is comprised of two wound toroids encapsulated in a chemically resistant nonconductor made of polyetherether ketone (PEEK).

Measurement is made inductively via magnetic coupling between the solution and the toroids. Because measurement is made inductively, without electrodes that can be affected by erroneous resistances from foulants or coatings, these sensors are virtually impervious to all but thick layers of foulants.