What is the typical diameter of a drain hole placed on each pan of aluminum bus work?

The typical diameter of a drain hole placed on each pan of aluminum bus work is 1/4 inch. This size is considered optimal because it allows for the effective drainage of moisture and condensation that can accumulate within the bus work pans. Proper drainage is crucial in electrical systems to prevent moisture-related issues such as corrosion, which can lead to failures in the bus work and, consequently, in the entire electrical installation.

Selecting a drain hole diameter that strikes a balance between allowing adequate drainage while avoiding excessive material removal is key. A 1/4 inch diameter is large enough to facilitate quick drainage, but not so large that it compromises the structural integrity of the aluminum bus work. This careful consideration in design helps ensure longevity and reliability of the electrical components in a substation environment. Other options would either be too small, potentially leading to blockage or inadequate drainage, or too large, risking structural strength.