What are the specific requirements and standards for the waterproof and dustproof structure design of stainless steel outdoor cabinets?

Specific requirements for waterproof and dustproof structure design of stainless steel outdoor cabinet+corresponding national standard

1. Basic protection classification standard (core basis: GB/T 4208-2017 IP Code of Enclosure Protection Grade)

1. The meaning of IP two digits

First place: dustproof grade; Second place: waterproof grade, minimum configuration of outdoor cabinets is IP54, outdoor rain/coastal recommended IP55, deep-water spray/heavy rain IP56.

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Protection level, dustproof requirements, waterproof application scenario, cabinet application scenario

IP54 dustproof, dust can't be accumulated in large quantities, and it doesn't affect the operation of the equipment. It can prevent splashing water, rain and daily rain. Urban roadsides, green belts and lightly shielded outdoor cabinets.

IP55 is completely dust-proof and intruded, and only a small amount of dust penetrates into low-pressure spray rainwater in any direction, and the outdoor cabinet (mainstream) in the factory area and wall hanging is unobstructed.

IP56 is completely dust-proof, so dust can't enter the scene of high-pressure water spraying, heavy rain scouring docks, construction sites and strong rain at the seaside.

Compulsory standard basis

GB/T 4208-2017: IP is the only national standard for judging waterproof and dustproof, and the ex-factory rain and dustproof tests are carried out according to this;

GB/T 30038-2013 General technical requirements for outdoor cabinets of electrical equipment;

Refer to YD/T 5175； for communication outdoor cabinet; Refer to DL/T 375 for power cabinet.

Second, the waterproof structure special design rigid requirements

(a) the roof waterproof structure (the first waterproof barrier)

The roof must be set with a one-way drainage slope of ≥ 5, and flat roof is strictly prohibited;

The four sides are bent integrally to raise the waterproof eaves (the height of the water retaining edge is more than or equal to ≥15mm) to form a peripheral water retaining groove to block rainwater from flowing into the door crack along the side plate;

Splicing of the top cover and the upper frame of the cabinet: full welding sealing+external weather-resistant sealant plugging, and only spot welding is prohibited; Flat-fell seam is forbidden to open upwards;

The outdoor exposure cabinet can be equipped with an independent external sunshade roof to isolate direct rain and reduce the high temperature aging of rubber strips.

(2) Double-layer labyrinth waterproof structure of door panel (core waterproof structure)

The door frame adopts a double-layer bending labyrinth groove: the outer retaining groove and the inner sealing groove are two barriers, and the rainwater first falls into the outer groove and is discharged from the diversion port, and cannot reach the sealing strip directly;

Sealing strip requirements:

Material: EPDM EPDM foam rubber, UV-resistant, -40℃~120℃ weather-resistant, PVC and ordinary rubber are prohibited;

Structure: a whole continuous adhesive tape without breakpoints, with hollow foam section and compression of 30% ~ 40%; 45 miter bonding is adopted at the splicing place, leaving no gap;

The edge of the door panel is thickened, and after closing, the rubber strip is evenly pressed all around, and the gap between the doors is even ≤ 0.8 mm;

An integrated waterproof and dustproof lock cover is added to the door lock and lock lever, and a rubber dust plug is built into the lock core, so that the lock hole is not directly exposed to the rain.

(3) Ventilation, heat dissipation and waterproof structure (ventilation ≠ water leakage, no direct shower opening)

Rain-proof louver structure: the louver is inclined downward by 30 ~ 45, with overlapping blades for shielding, stainless steel dust-proof mesh is installed on the outside, and detachable polyester dust-proof filter cotton is installed on the inside;

Forced cooling fan: the outer side is equipped with an integrated rain-proof hood with drainage holes, and the inner side of the fan is equipped with a dust-proof filter screen;

Waterproof vent valve (required to solve condensation+internal and external air pressure balance):

Installation location: the upper side of the cabinet, away from the direct rain shower area;

Function: balance the pressure difference inside and outside the cabinet, discharge the internal moisture, and prevent rainwater and dust from entering in the opposite direction;

Quantity: 1 small cabinet, 1 floor cabinet above 1.2m and 1 floor cabinet above.

(4) Bottom wiring and drainage waterproofing

Cable incoming wires are uniformly arranged at the bottom of the cabinet, and it is forbidden to open holes in the upper and middle sides of the cabinet;

The inlet hole is equipped with stainless steel waterproof glen head, and the periphery of the opening is sealed with neutral weather-resistant silicone adhesive, and the gap between the cable and glen head is completely blocked;

Φ6~Φ8mm condensation drain hole is reserved at the lowest part of the cabinet, and a pluggable rubber plug is built in; Wet environment is open all year round, dry environment can be blocked, and internal condensation water can be automatically discharged;

The floor cabinet must be equipped with a stainless steel lifting base with a height of ≥150mm, so as to isolate the ground water and sediment from soaking the bottom of the cabinet.

(5) Waterproof requirements for welding and splicing gaps

All side plates, top plates and base seams of the cabinet are fully welded, and intermittent spot welding is prohibited;

After the weld is passivated by pickling, the external part is coated with weather-resistant sealant, and the tiny capillary gap is blocked inside and outside;

The cabinet body is not designed with inward concave water storage grooves and bending dead angles, and all corners are in arc transition to avoid long-term accumulation and corrosion of sediment water.

Third, the dustproof structure special hard design requirements

All exposed openings (ventilation, incoming lines and inspection openings) must be provided with multi-layer dustproof barriers: double-layer protection of louver filter screen+cotton filter/rubber seal;

The vent valve adopts ePTFE waterproof and breathable membrane with micron-sized aperture, which blocks dust, water vapor and liquid water and only allows gas to circulate;

The gaps of door panels, door frames and locks are blocked by labyrinth grooves and sealing strips, and there is no exposed through gap;

Cabinet in mining area and dust factory area: increase the ventilation cotton filter area, and design the drawable cotton filter access port to facilitate regular replacement;

There is no exposed open trunking inside the cabinet, and the cable trunking is covered with dust-proof cover plate.

Four, hardware, accessories waterproof and dustproof standard requirements

Hinge: 304/316 stainless steel exposed waterproof hinge, with dust-proof waterproof glue sleeve on the hinge shaft. Ordinary iron hinge and built-in hidden hinge are prohibited (easy to get stuck by water and dust);

All fasteners: stainless steel screws, spring pads and flat pads, to prevent galvanized iron parts from leaking into the dust due to corrosion and expansion;

Sealant: only outdoor neutral weather-resistant silicone adhesive is used, which is resistant to ultraviolet rays and does not crack. Indoor ordinary glass adhesive is prohibited;

Filter cotton: polyester dust-proof filter cotton, waterproof and breathable, not easy to powder, long-term outdoor does not break off.

V. Supporting test standard for IP protection (mandatory requirement for ex-factory inspection)

1. Dust-proof test (according to GB/T 4208)

IP5X: The dust circulation in the cabinet lasts for 8 hours, and there is no visible dust accumulation inside the disassembled cabinet, so the equipment is not affected;

IP6X: The dust box is closed for 24h, and there is no dust inside.

2. Waterproof rain test

IPX4: water is splashed on all sides for 5min, and there is no water seepage inside the cabinet;

IPX5: low-pressure spray water gun, spraying all sides of the cabinet at any angle for 3 minutes, without water;

IPX6: High-pressure and strong water jet flushing, simulating rainstorm and high-pressure flushing scenes, with no leakage inside.

3. On-site qualification criteria

There are six key positions: door crack, welding seam, air vent, wire inlet hole, lock and air vent valve. After the test, there is no water accumulation or water seepage in the cabinet.

Six, common structural design defects (do not meet the waterproof and dustproof standards)

The flat roof has no waterproof eaves, no drainage slope, and rainwater flows directly into the crack of the door;

One-way sealed labyrinth-free water retaining tank, rain directly impacts the rubber strip;

Using ordinary solid rubber strip and PVC rubber strips, outdoor short-term aging cracking;

High-level openings at the top and sides are ventilated, without rain-proof louver hood, and rainwater is directly poured;

No vent valve is completely closed, and water is condensed due to temperature difference, which indirectly damages protection;

Spot welding and splicing, the weld is not glued, and the gap seeps into the ash;

There is no raised base at the bottom, and the ground rain soaks the bottom weld, which is corroded and worn out for a long time.