Environmentally-sealed connectors are an ideal interconnect solution for heavy-duty and harsh, corrosive environment applications. There are very wide ranges of tough, harsh environments that require rugged, sealed cable, plugs, receptacles and connectors. Today’s technology allows function reliability withstand exposure in environments with extreme temperatures, high vibration, impact, liquids, chemicals, etc.

There are two standards used to measure the levels of how protected a connector is and what kind of environment it is designed and manufactured to withstand. NEMA ratings and IP ratings both define degrees of protection against substances such as water and dust, but use different tests to determine their enclosure types (NEMA and IEC standard 60529).

NEMA, National Electrical Manufacturer Association, is largely used in North America and is geared towards industrial applications. IEC, the International Electrotechnical Commision, is, as its name suggest, the standard (IP) used on the international stage. IP ratings only cover protections against water and solids. NEMA includes standards against corrosion resistance as well as differentiation between possible hazardous and non-hazardous environments.

The ratings for both are:

NEMA (for full chart see here)
Type 1 Indoor use to provide a degree of protection to personnel against access to hazardous parts and to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt)
Type 2 Protections of Type 1 plus and provides a degree of protection with respect to harmful effects on the equipment due to the ingress of water (dripping and light splashing)
Type 3 Indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and windblown dust); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow); and that will be undamaged by the external formation of ice on the enclosure.
Type 3R Enclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow); and that will be undamaged by the external formation of ice on the enclosure.
Type 3S Indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and windblown dust); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow); and for which the external mechanism(s) remain operable when ice laden.
Type 3X Indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and windblown dust); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow); that provides an additional level of protection against corrosion and that will be undamaged by the external formation of ice on the enclosure.
IEC (see here for full chart)
1st Number Projection Against Solid Objects 2nd Number Projection Against Liquids
0 No Protection 0 No Protection
1 Protected against solid objects over 50 mm (e.g. accidental touch by hands) 1 Protected against vertically falling drops of water
2 Protected against solid objects over 12 mm (e.g. accidental touch by fingers) 2 Protected against direct sprays up to 15 degrees from vertical
3 Protected against solid objects over 2.5 mm (e.g. accidental touch by tools and wires) 3 Protected against direct sprays up to 60 degrees from vertical
4 Protected against solid objects over 1 mm (e.g. accidental touch by tools, wires, and small wires) 4 Protected against sprays from all directions – limited ingress permitted
5 Protected against dust-limited ingress (No harmful deposit) 5 Protected against low-pressure jets of water from all directions – limited ingress permitted
6 Totally protected against dust 6 Protected against strong jets of water (e.g. for use on ship decks) – limited ingress permitted
7 Protected against the effects of temporary immersion between 15cm and 1m. Duration of test 30 minutes
8 Protected against long periods of immersion under pressure
Graphs are great when you know what they mean, so what does this mean?

When you are constructing your requirements you’ll decide what level of solid object ingress is acceptable and then you’ll decide what level of liquid ingress is acceptable. These determinations will provide you a two digit code resulting from the IEC 60529 IP code.

The First Digit is your indicator for solid object ingress or protection:

IP 5# can be achieved with tight-fitting parts; no supplementary seals (dust inside is okay but can’t interfere with function)

IP 6# requires seals to keep dust completely outside of the enclosure (no dust visible inside enclosure after exposure testing)

The Second Digit is your indicator for fluid ingress or protection:

IP #0, #1, #2 and #3 can SOMETIMES be achieved with tight-fitting parts and no supplementary seal but this is dependent upon knowing parts installation orientation.

IP 64, 65, 66, 67, 68 all require compliant (“rubbery”) seals.  (while not mandated, if the second digit is 4 or higher, the first digit becomes a 6 for free since the seal is needed.  In other words, while an IP 55 designation is supported by the standard, you’ll likely never see this).

Why does this matter and how does it affect my interconnect project? 

So, whether your application is set amidst the extreme colds of the Arctic, the unbearable heat of the desert, surrounded by the high tech of military-grade equipment or within the walls of a hospital or physician’s office, every environment presents its own unique set of problems and issues that an interconnect would need sealing to protect it. Most interconnect projects, whether it’s inclement weather, sterilization or any other source of outside wear, will have some sort of something that could potentially wear the connector down and, eventually, ruin the connector. Working with a knowledgeable team, like the team at ATL, with awareness of the potential environmental challenges, can plan for and implement proper sealing techniques that can not only make your application a success but make it last the full life expectancy.