Which IP or NEMA rating to ask for in an electrical enclosure on the coast

The IP code has two digits. The first is about solids and dust: a 5 protects against dust in limited amounts and a 6 means an enclosure that is dust-tight. The second is about water: a 4 withstands splashing, a 5 water jets and a 6 powerful jets; higher digits refer to immersion.

So an IP54 is usual indoors with some dust and moisture, an IP65 outdoors under cover and an IP66 where jets or heavy rain fall. The exact rating is set by the project engineer.

NEMA classifies enclosures by type of use. Type 1 is for indoors with basic protection; 12, for indoors with dust and dripping; 3R, for outdoors against rain, without being watertight; 4, watertight even against a hose; and 4X adds corrosion resistance.

IP and NEMA are measured with different tests, so there is no exact table of equivalents. If your specification uses one of the two, tell us which when you ask for a quote.

In a dry, ventilated plant room, protection against dust and contact is usually enough. Outdoors the rain comes in, and the enclosure needs a roof, seals and well-made cable entries. By a pool, constant humidity and cleaning water are added. Facing the sea, salt air attacks hinges, latches, bolts and edges, and the material matters as much as the seal.

Look at what happens around it too: a sprinkler that wets the enclosure every morning or a floor where water pools ages it faster than the climate itself.

A well-sealed enclosure can still fail if its sheet or its hardware cannot stand the surroundings. We cut carbon steel, galvanized steel, stainless steel and aluminum; stainless and aluminum behave well facing the sea, and painted carbon steel works if it is checked and touched up in time. Hinges, latches and bolts have to resist as much as the enclosure: a common bolt in a stainless enclosure rusts first.

More protection is not always better. A sealed enclosure holds the heat of the equipment and, with the change in temperature between day and night, moisture can condense inside. Depending on the case, it is solved with filtered ventilation, a small heater or a sunshade over the enclosure, and each solution is decided with the engineer because it changes the protection rating.

Say whether the enclosure goes indoors, outdoors, by a pool or facing the sea; the rating the project asks for, if it has one; which equipment it will hold; whether it needs viewing windows, a lock or a seal; and whether it goes on a wall, on the floor or on a base. In our plant in Bávaro we draw it in 3D, cut, bend, weld and paint it, assemble the electrical side, and it leaves with its QR code plate.