What Causes The Surface Of Copper Terminal Blocks To Turn Green? Here Are A Few Easy Ways To Fix It

Many people find when inspecting the distribution box that the originally golden-yellow copper terminal block has been covered with a layer of emerald green "coat". This green substance is actually verdigris, scientifically known as basic copper carbonate. The greening of copper distribution block copper is usually due to long-term exposure to humid air, where copper reacts chemically with oxygen, carbon dioxide, and water molecules.

Why do copper terminal blocks turn green?

The root cause of the discoloration lies in the interplay between environmental factors and material properties.

• Excessive humidity: In high humidity environments, moisture adheres to the conductive metal surface, accelerating the electrochemical corrosion process.

• Acidic gases: If there is ammonia gas emitted from chemical fumes or excrement in the vicinity, the reaction rate will increase exponentially.

• No plating: Bare copper material is directly exposed to air, lacking the protective barrier of a tin or nickel layer.

How to deal with the greening phenomenon?

After the copper surface of the copper terminal block turns green, its conductivity will be affected due to increased resistance. You can try gently sanding away the surface oxide layer with fine sandpaper to reveal the shiny, uncolored copper underneath. For cases of deep corrosion, it is recommended to directly replace the copper terminal blocks with those featuring a high-quality plating. During installation, apply an appropriate amount of conductive grease to the connections to prevent direct contact between the metal and air.

Regularly cleaning dust from inside the distribution cabinet is also crucial. Dust easily attracts moisture, accelerating corrosion. Maintaining a dry environment is the long-term solution to the copper terminal strip oxidation problem.