IP65 means the connector is fully dust-tight (first digit 6) and protected against water jets from any direction (second digit 5).
They are protected against water jets but not against immersion. Temporary or continuous immersion requires IP67 or IP68 respectively.
The difference is in the second digit: IP65 protects against water jets from any direction, IP67 against temporary immersion (up to 1 m, 30 minutes). The second digit is not cumulative – a pure IP67 product is not automatically tested against water jets. If both are required, manufacturers specify a combined rating such as IP66/IP67.
In industrial automation, machine building, outdoor sensors and installations where dust occurs and occasional cleaning with water jets takes place.
Yes, for typical outdoor use involving rain, water jets and dust. If the connector may be temporarily submerged, IP67 is required. Note that the IP rating says nothing about UV resistance, temperature range or corrosion protection – these must be considered separately depending on the location.