If they are in a 3R type enclosure, the wiring and terminations are not supposed to be getting wet. The NEMA test requirement for 3R panel is the entire top, and all exposed sides are sprayed with water at 5 psi for one hour at a rate to cause water to rise 18" in a straight sided pan placed beneath the enclosure. The evaluation is: no water shall have reached live parts, insulation or mechansims. If the panel is a NEMA 4 or 4X then the same test is used but the evaluation is: no water shall have entered the enclosure.
Don(resqcapt19)
