The BC1 supports standards ATX PSUs with a maximum depth of 217mm if drives are installed. In vertical mode, this is reduced to 180mm as the gap between both feet is reduced.
In vertical setup, the foot to foot gap is 188mm, which defines the maximum depth of a PSU that can fit. Cables can pass through the opening in the foot, so no allowance for the cables is required.
PSUs of more than 10kg may put excessive stress on the legs so they should be used with caution