Printed circuit boards (PCBs) come up against moisture, vibration, thermal shock and contamination during their lifespans, so the protection of PCBs is instrumental to ensure the ongoing performance reliability of an electronic device…

Plus, with manufacturers aiming to meet net-zero commitments and increasingly focusing on reducing electrical waste, improving the durability of electronic products is more important than ever.

So, what are the most common protection methods, and how can electronics manufacturers decide the most suitable type for each project?

Potting and encapsulation

Potting and encapsulation are two common techniques for protecting sensitive components and sub-assemblies, such as the PCBs and cable joint assemblies used in automotive or marine equipment.

Both techniques involve submerging an electronic component or sub-assembly in a resinous material.

Potting creates a shell (or pot) around the PCB and its parts by encasing it in poured resin. Encapsulation, on the other hand, is when a component is dipped into a resin mould and coated. As the resin hardens, the components are removed from the mould to be placed in the assembly. The subtle difference between encapsulation and potting is that the mould is not part of the final product.

For both techniques, the coating is set — either by air drying, oven drying or curing with UV light — to protect the PCB against potential damage.

When deciding on the types of compounds used to protect the components, manufacturers must consider the advantages of each material and the level of protection required…

Silicone coating is often used as it provides high flexibility and is resistant to water, chemicals and UV light damage.

Epoxy is a less costly yet more rigid protective coating material than silicone. However, although it is resistant to temperatures up to 200 degrees, epoxy’s downfall is that it is often brittle at lower temperatures.

Urethanes — another option — are ideal for low-temperature environments, but they do not offer the same level of resistance to harsh chemicals and high temperatures as silicone and epoxy coatings.

Temperature resistance is a critical consideration for PCB coating, especially if they are being used for equipment in explosive atmospheres and high-risk or high-pressure environments such as industrial sites. In these cases, conformal coating may be the more effective option.

Conformal coating

Conformal coating is a lightweight alternative to potting and encapsulation that typically involves dipping, brushing or spraying the coating onto the PCB.

This is an ideal solution if manufacturers require PCBs with a precise thickness to be fitted into smaller devices.

Like potting and encapsulation, the compounds chosen depend on the end-product requirements and environment.

Silicone and acrylic offer all-around protection and high flexibility at a reasonable price — but silicone only has moderate humidity resistance, and acrylic has limited chemical resistance.

Polyurethane coatings, however, are highly flexible and ultra-durable, with excellent resistance to harsh chemicals and environmental conditions.

Hand your project over to the specialists

No matter which type of coating is used, proper application is the most critical factor.

Whether manufacturers choose potting and encapsulation or conformal coating for their PCBs, nothing will sufficiently protect them if not done to a high standard — running the risk of system damage and failure…

Many businesses — particularly in demanding sectors like automotive, marine and industrial —employ the help of electronics manufacturing specialists like EC Electronics to ensure they are developing intrinsically safe products.

Much of what we manufacture is embedded within safety-critical or failsafe systems, where control, consistency and product reliability are paramount. This is why we only manufacture electronics to the highest quality levels and IPC-A-610 and IPC/WHMA-A-620 standards of workmanship.

Our Quality Management System (QMS) is also certified to EN ISO/IEC 80079-34:2018 in line with IECEx and ATEX Directive 2014/34/EU, ensuring our products meet the requirements for products certified for use in potentially explosive atmospheres.

We provide specialist potting, encapsulation and PCB conformal coating services for various industries and applications. To discuss your next PCB project with us, please get in touch with our friendly customer service team at sales@ecelectronics.com or call 01256 461894.