Outdoor Durability for EV Charging Enclosures: IP, IK and Vandal Resistance

Durability specifications are the most commonly misused part of an enclosure brief. Words like weatherproof and vandal resistant sound like requirements but give a fabricator nothing to build. IP and IK ratings do give something to build, provided they are chosen for the actual site and verified on the actual assembly.

Turning Vague Words into Testable Requirements

"Weatherproof" and "vandal resistant" are not specifications. They are descriptions of an outcome, and they leave the fabricator to guess what the buyer means.

The most common failure in this area is a specification written for the product's marketing rather than for manufacture. A single sentence naming the ratings and the environment removes almost all of the ambiguity.

IP Ratings for Public Chargers

The IP rating of a charger is usually two ratings: one for the cabinet and one for the connector interface. Only the first is a sheet metal question, but a brief that does not separate them will produce confusion at the first design review.

• The cabinet is commonly specified between IP54 and IP66 depending on exposure and cleaning method.
• The connector is a separate assembly with its own rating, often higher, and it is supplied by the connector vendor.
• The cabinet-to-connector interface is the joint where both parties have a responsibility, and it should be defined on the drawing.

Within the cabinet, the same rules apply as for any outdoor enclosure: flat gasket surfaces, controlled compression, every entry sealed, and no louvre that offers a straight path for water.

Impact and the Details That Actually Resist It

Impact resistance is decided by the structure, not by a single panel thickness number.

• Edge returns. A formed return on an exposed panel multiplies its resistance for very little weight.
• Fixings. Concealed, security or non-removable fasteners where the public can reach them.
• Frame behind the panel. A stiff frame prevents a local dent from spreading and jamming a door.
• Recessed features. Screens and readers set back behind a lip are much harder to attack than flush-mounted ones.
• Replaceable wear parts. Holsters, cables and connector holders should be designed out rather than built in.

Corrosion Protection for Exposed Sites

Durability in the field is usually corrosion, and corrosion is usually a specification problem.

• State the corrosion category and let the coating system follow from it.
• Protect cut edges and holes, because that is where coated steel begins to corrode.
• Use light colours in direct sun to reduce solar gain, which keeps the electronics cooler and slows coating degradation.
• Design for drainage so water does not stand at the base or pool on a flat roof.
• Consider stainless or duplex systems on coastal and heavily exposed sites rather than relying on a heavier coat of the same system.

Gaskets, Compression and Checking

A gasket is only as good as the surface it seals against and the compression it receives.

• Material choice: matched to the temperature range and to UV exposure, because an exposed charger reaches higher surface temperatures than a sheltered cabinet.
• Compression: set by hinge, stop and latch geometry, not by how hard the last person closed the door.
• Continuity: a gasket line that is interrupted by a latch, a hinge or a weld is a potential path.
• Inspection: gasket compression and gasket line flatness belong on the first-article checklist.

Inspecting Durability on the First Article

Designing for Service Life, Not Just First Delivery

The most durable charger is not necessarily the heaviest. It is the one whose wear parts can be replaced and whose failure modes were anticipated.

• Define the wear parts: connector holster, cable management, door hardware, gaskets, filters.
• Make them replaceable without dismantling the electronics enclosure.
• Write the maintenance interval into the documentation, particularly for filters if forced cooling is used.
• Keep a first-article record of the sealing and alignment checks, so later production can be compared against an agreed baseline.

Our Approach to Durability Specifications

• We build to a stated IP and IK requirement and we ask for the site environment, because durability without a site description cannot be designed.
• We fabricate the edge returns, stiffeners, concealed fixings and drainage features that actually deliver impact and corrosion performance.
• We document the sealing and alignment checks on the first article, so the agreed construction is reproducible.
• Where a formal IP or IK test is required, it is arranged with an independent test house and stated explicitly in the order.
• We do not certify the electrical or safety performance of the charging equipment, and we do not supply the connector assemblies.

Send the site conditions, the target ratings and the drawings, and the durability requirement can be translated into a construction that can be built and checked.

Frequently Asked Questions