Linear Polarization Resistance (LPR) Probe is made by three electrodes (Working Electrode, Counter Electrode and Reference Electrode) and when it is connected to the AE-Corr-meter it gives instantaneous corrosion rate unaffected by solution resistance. 

Electrodes of different shapes are suitable, depending on monitoring condition:

Protruding Electrodes (for instantaneous reading, specially designed for water treatment plants).

Tubular Electrodes
(for periodical or continuous monitoring of a pipeline or of a petrochemical plant).

Fixed LPR Probe  is permanently immersed in the fluid, and its replacement is possible only when the plant is not working.

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