Dissimilar Metals

Avoiding contact of dissimilar metals to prevent galvanic corrosion is not only a good idea, it is a code requirement. NEC 110.14 requires that dissimilar metal conductors shall not inter mix in a terminal or splice unless so listed, and 344.14 states that dissimilar metals in contact anywhere in the system shall be avoided. 344.14 goes on to state that aluminum and steel RMC may be mixed. My solution has been to check against a galvanic action chart (MLT-STD-889B) showing materials by anodic index, and ensuring that mixed metals where they occur are seperated by no more than 0.15V to 0.25V. This aligns with mixing aluminum with low carbon rigid steel, or aluminum with galvanized, however it may increase product quality to ensure that galvanized is not mixed with low alloy steel in harsh environments.