Page 10 - Pipelines

Protection of cathodic protection

rectifiers

In case of impressed current cathodic protection, the required Since the cathodic protection rectifiers are galvanically con-
protective current is produced by a mains-powered rectifier nected to the pipeline, anodes, system earth and reference
and fed into the protection object, for example the pipeline, electrode, overvoltage can occur which may interfere with or
via impressed current anodes. Modern rectifiers additionally even destroy the devices and presents a high risk of fire.
feature a control device which detects the protection po-
tential of the pipeline against a reference electrode (e.g. Cu/ The DEHN protection solutions can cope with the following
CuSO electrode) and automatically sets the optimal cathodic overvoltage:
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protective current. • Transient overvoltage (direct and indirect lightning effects
and switching operations)
A cathodic protection system mainly consists of: • Temporary overvoltage (short-circuits resulting from trac-
• Cathodic protection rectifier for the protective current tion current and high-voltage systems)
• Control devices with reference electrode
• Impressed current anodes

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