An industrial PoE switch listed as IP40 belongs indoors; one rated IP67 can sit in water or take a pressure wash. The two digits after "IP" decide whether dust, spray or short submersion can reach the electronics — pick wrong and you get repeated failures or a dead unit. The choice comes down to one question: where will the switch actually be mounted?
IP rating has two digits: the first is dust protection, the second is water protection.
IP40 resists objects ≥1 mm but has no water seal; IP67 is fully dust-tight and survives 1 m submersion for 30 min.
Choose by mounting location: cabinet → IP40, outdoor rain → IP65, washdown or possible flooding → IP67.
The first digit is dust, the second is water. A "4" keeps out solids ≥1 mm (screwdriver, cable) but fine dust still gets in; a "6" is fully dust-tight. A "0" means no water protection; "5" resists low-pressure spray from any direction; "7" survives short immersion.
| Rating | Dust | Water | Typical spot |
|---|---|---|---|
| IP40 | Solids ≥1 mm (fine dust enters) | None | Indoor cabinet, control room |
| IP65 | Fully dust-tight | Low-pressure spray | Outdoor pole, tunnel wall |
| IP67 | Fully dust-tight | Short submersion | Conduit, underground, wet lines |
Note: IP40 blocks tools and cables but not fine dust, and it has no water seal at all. It protects against foreign objects and accidental contact, not the environment.
IP40 — inside cabinets, distribution boxes and indoor control rooms, where there is no spray and the main risks are debris and accidental contact.
IP67 — outdoor enclosures, utility tunnels, mines, and food or aquaculture washdown lines, where short soaking or high-pressure cleaning is routine.
IP65 sits between: fully dust-tight and spray-proof, but not submersion-rated. It is the common choice on outdoor poles and tunnel walls.
Tip: Don't over- or under-spec. IP67 indoors wastes money; IP40 outdoors guarantees regret. Match the rating to the location, not to the budget you happen to have.
Warning: A sealed IP67 enclosure sheds heat only through its case. Confirm the thermal design so you don't trade water protection for a temperature-rise failure in a hot cabinet.
Ingress protection is one line on the datasheet. A managed switch that is IP67 still needs wide-temperature operation (–40 to 75 °C), surge protection (6 kV) and anti-vibration to survive the site. Treat them as equals with the IP code, not afterthoughts.
Can IP67 be submerged long term? No. The rating covers short immersion (1 m / 30 min). Long-term submersion needs a dedicated submersible housing.
Is IP40 enough indoors? In a sealed cabinet, yes. But in a dusty workshop, choose an IP6x dust rating rather than stopping at IP40.
Does a higher rating always cost more? Generally yes, and the fully sealed thermal design is more complex — weigh the trade-off against the real environment.
How do I verify a real rating? Check a third-party certification report; don't trust the vendor's label alone.
Which Rayin switch fits a wet site? Rayin industrial PoE switches come in IP65/IP67 rugged builds with wide-temperature and 6 kV surge protection for tunnels, mines and washdown lines, with a Mini GPON OLT for fiber uplink.
IP40 vs IP67 comes down to one question: where is the switch mounted and will it meet water? Indoor cabinet → IP40, outdoor rain → IP65, possible immersion → IP67. Choose the industrial PoE switch whose rating matches its mounting spot — cabinet, pole or washdown line — and you spend neither too much nor too little.
About the author: Sara — Sara is a Customer Manager at Rayin with over 10 years of experience in the communications field. In her free time, she enjoys badminton and swimming.
About Rayin: Shenzhen Rayin Technology Co., Ltd. — Company Profile
