Let me pull out and dust off the Electrical Engineer's Handbook tonight for the skin effect calcs [both Copper and Aluminum materials, and the various shapes and types of conductors - such as tubular circular, tubular square, complete circular, etc.].
The Hz for the faults would be at the fundamental Hz - maybe including any relavent Harmonics if they could contribute to the fault significantly.
The wavelengths / Hz will remain, however the peaks will rise drammatically.
The fault may impose harmonics [or something like sidebands], but the fault calcs would be made at the fundamental Hz.
I'll double check on this while getting the skin effect data.
Scott SET
