For rural lighting projects in Africa, it is recommended to tin plate the busbars inside the electrical ready board, which is the preferred solution to ensure long-term reliable operation. Bare copper can only be considered in extremely dry, highly IP protected, and budget constrained scenarios. In rural Africa, there is a large temperature difference between day and night, and high humidity during the rainy season. Condensation is easily generated in electrical ready boards, accompanied by dust, salt spray, and sulfides in some areas. Bare copper will quickly oxidize and turn black in such environments, and the contact resistance at the overlap position will continue to rise, causing joint overheating and burnout faults. The on-site operation and maintenance conditions are weak, and the difficulty of fault repair is high.

The tin plating layer can isolate water vapor and dust, suppress oxidation and corrosion of the copper substrate, stabilize and maintain low contact resistance of the overlap surface, effectively control temperature rise, reduce the risk of power outages on site, and improve the weldability of busbars, suitable for batch assembly. The recommended coating thickness is ≥ 5 μ m, with a focus on ensuring the integrity of the coating in the bolt overlap area to avoid coating damage.

If bare copper is used, even if the IP rating of the electrical Ready Board Box meets the standard, long-term temperature and humidity cycling will still accelerate the oxidation of the busbars, which is only suitable for short-term trial projects and cannot meet the long-term service life requirements of projects such as Eskom. The use of tin plated busbars will slightly increase material costs, but significantly reduce the overall cost of on-site repair and replacement, which is in line with the design goal of low maintenance and long service life for rural power distribution in Africa. Conductive anti-corrosion grease can be added to the overlapping surface to further enhance the stability of anti-corrosion and electrical connections, which is a mature and reliable engineering solution in this scenario.