Sometimes also known as a constant current meter, this equipment is characterized by large internal resistance, generally not affected by external resistance or reverse voltage when working, much like a constant current stabilizer. This rectifier is particularly suitable for forcing out stray currents on pipes with a fairly poor covershain quality, where the tube/ground potential is usually proportional to the current discharged. When INSTALLING constant CURRENT PROTECTION, EVEN FAIRLY SMALL FLUCTUATIONS IN tube/GROUND POTENTIAL SHOULD BE CONSIDERED.
Constant-current controlled protection rectifiers are sometimes used for cathodic protection of pipes placed under forward tram tracks. Generally, the stray current should be discharged in the natural direction, that is, the applied current cathodic protection should be implemented at a distance of several kilometers on both sides of the railway crossing point.
Because of the difficulty of testing, the protection status of deep casing cannot be known in the cathodic protection of well casing. Sometimes the current density is used as the criterion of the cathodic protection level of casing. At this time the constant current meter can also play its role in this field.
