Differential Electrode measurement technique uses three electrodes instead of the two normally used in conventional pH sensors. Process and reference electrodes measure the pH differentially with respect to a third ground electrode. The end result is unsurpassed measurement accuracy, reduced reference junction potential, and elimination of sensor ground loops. These sensors provide greater reliability, resulting in less downtime and maintenance. The unique, replaceable salt bridge holds an extraordinary volume of buffer to extend the working life of the sensor by protecting the reference electrode from harsh process conditions. The salt bridge simply threads onto the end of the sensor if replacement is needed. Encapsulated design of the preamp protects the sensor’s built-in preamp from moisture and humidity, ensuring reliable sensor operation. The preamp in the pH sensor produces a strong signal, enabling the sensor to be located up to 914 m (3000 ft.) from the analyzer.