Zinc Grounding cells have long been used to allow the passage of fault current and lightning strikes around isolated pipeline couplings or flanges without causing harm to the pipeline isolator itself. The grounding cells provide sufficient resistance to prevent normal cathodic protection current from passing while allowing a high fault current path around the pipeline isolator.
Zinc grounding cells are usually made from two zinc anodes isolated by a 25mm non-metallic spacer and then packaged in a cloth bag filled with a low resistance backfill mixture consisting of 75% Gypsum, 2O% bentonite and 5% sodium sulfate.
Each Anode is connected with 1C x 10 sq mm or 1C x 25 sq mm cable directly with the cores of the Anode.
Typical grounding cell installations are done at Oil & Gas Pipeline, Water Pipelines, Power stations, Oil storage tanks and transmission line towers.
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