Many electronic items require waterproofing, from smart speakers for swimming pools to drones that need protection from the elements. Effectively protecting electronics equipment from moisture depends heavily on the design of a product’s waterproofing enclosure. Here are four keys to designing an electronics enclosure so that it stays waterproof under wet conditions.
1. Use IP Code Testing
To provide an objective way to evaluate waterproofing quality, a standard measurement system has been set up by the International Electrotechnical Commission, the Swiss-based association that publishes international standards for the electrical and electronics industries. The International Protection Marking (Ingress Protection Marking) code (IP Code) measures waterproofing on a scale of 0 to 9K.
A 1 on the scale represents being waterproof against dripping water, while an 8 indicates protection against sustained immersion under pressure, and a 9K rating means proof against powerful high-temperature water jets. Getting IP tested is the best way to ensure waterproofing quality and to work out any bugs in your product.
2. Follow Simple Structural Designs
Testing has found that simple circular designs, such as o-rings and gaskets, provide the best waterproofing seal for electronic enclosures. A circular shape promotes a uniformly distributed and continuous force, which makes for a more reliable seal. Designs that rely on compression, such as bulkhead fittings, work better than designs such as wedge fits.
Minimizing your design’s number of surface interfaces also improves sealing. A seal between two parts is easier to seal than one between three parts. For situations that do require more complicated shapes, a good solution is a tortuous design with multiple twists.
3. Select Stable Materials
Choosing the right materials also affects your seal’s waterproofing reliability. Materials which grow or shrink, become distorted under pressure or lose their stiffness may not maintain their seal after prolonged use under stressful conditions. Choose a material that remains physically and chemically stable under conditions corresponding to the intended use of your product. For example, fluorocarbon and silicone o-rings can tolerate a wide range of temperatures without changing their size or shape, and they also resist chemical alteration, including the solvent effects of water, making them excellent for electronics uses.
If your product isn’t built to accommodate an o-ring or gasket shape, another option is to incorporate an appropriate elastomer such as Viton through overmolding and directly attaching half of your seal to your enclosed design. Other workaround solutions are using ultrasonic welding or liquid adhesives.
4. Keep Structures in Place With Solid Support
Providing support that keeps your seal in place is also critical for maintaining waterproofing. Seals such as o-rings must remain in the correct position to do their job. If a seal shifts out of position due to pressure, the seal may begin leaking, or it may completely fail.
To stay in place, o-ring and gasket mating surfaces must be properly fitted to their respective seals, which calls for precise measurements. Gaskets that aren’t circular and stand on their own should be supplemented with support from all sides so they don’t slip out of place. For seals intended to be used under intense pressure, circular o-rings provide a more reliable solution than ones made of materials such as regular rubber, paper or cork.
Follow Best Practices to Stay Waterproof
Designing your enclosure seal with simple shapes, stable materials and stabilizing support can help ensure reliable waterproofing. Test your design with a qualified IP Code testing service to make sure it will hold up under real-life conditions. Following these guidelines will help keep your product’s electronics component’s dry and safe.