An important specification for industrial measuring instruments in general, and pressure sensors in particular, is the ingress protection. In this context, an assumed typographical error in our data sheets for the PSD-4, PSD-30, PSD-31 and PSA-31 electronic pressure switches has frequently been pointed out to us. These data sheets state that these instruments meet both IP65 and IP67 ingress protection. And yes, that’s absolutely right.
The explanation for this is pretty simple. It comes from the fact that the two ingress protection types, and thus the underlying tests, differ completely. The supposedly “higher” ingress protection, IP67, does not, at the same time, also cover the “lower” ingress protection, IP65. These are two different ingress protection types with different specifications.
General consideration of IP65 and IP67 ingress protection
To clarify the “mystery” of the two ingress protection types, here is the technical explanation: In accordance with IEC 60529, the first characteristic numeral specifies the protection “against the ingress of solid foreign objects” and the second characteristic numeral the protection “against the ingress of water”. The ingress protection types provide “dust-proof” equipment (IP6x), protection against “water jets” (IPx5) and “temporary immersion” (IPx7). Not every instrument protected against immersion also withstands water jets and, vice versa, not every water-jet protected instrument is also protected against immersion. A small, but important difference in some applications.
IP65 and IP67 ingress protection with WIKA pressure switches
Our electronic pressure switches have been designed and tested for both ingress protection types. This is confirmed not only by WIKA in-house tests, but also by external tests carried out by independent test centres, for example, as part of UL approval. In particular, this means that the WIKA PSD-4, PSD-30 and PSD-31 electronic pressure switches meet IP65 ingress protection, meaning they are dust-proof and protected against water jets. In addition, they fulfil the IP67 ingress protection, meaning they are also protected against short-term immersion in water. The WIKA model PSA-31 also fulfils both ingress protection types and was specifically designed for sanitary applications.