An electrical unit mounting assembly, having a top, bottom, back and front, and including a partial enclosure, made of insulating material, defining a cavity having a mouth at its front and defining a through-hole leading to the cavity, at its back and a panel extending outwardly from the mouth, for at least 4 cm and having a front surface. In greater detail, the assembly is oriented in an upright manner so that its top is topmost, the through-hole is constructed so that liquid cannot be driven by gravity from inside the cavity, through the through-hole and wherein the front surface of the panel includes raised surfaces defining down channels to prevent a foreign surface from blocking liquid-flow down the down-channels.