Potting Compound Selection for EMI Filter PCBs – ELAPLUS PUR 1635 Polyurethane Potting Compound Delivers Waterproof, Flame-Retardant & Insulating Protection
EMI filter circuit boards are widely integrated into power supplies, electronic controllers, industrial equipment, communication hardware, new energy systems and other assemblies. Their core function is to suppress electromagnetic interference and stabilize circuit performance. Filter PCBs are densely populated with inductors, capacitors, solder joints, terminals, PCB traces, alongside plastic and metal housings. During long-term operation, these components are exposed to multiple hazards including moisture, dust, vibration, temperature cycling and electrical safety risks. Therefore, when selecting potting adhesive for EMI filter motherboards, full filling capacity alone is insufficient. Critical performance metrics to evaluate include electrical insulation, water & moisture resistance, flame retardancy, flexibility, low shrinkage, weatherability and adhesion to various substrates. For EMI filter PCB potting applications, Elaplus Functional Materials (Shanghai) Co., Ltd. recommends the two-component polyurethane potting compound ELAPLUS PUR 1635, which provides long-term stable sealing and electrical protection for filter circuit boards. Potting for EMI Filter Circuit Boards I. Why EMI Filter PCBs Require Potting Protection EMI filters are critical anti-interference components within power systems, commonly deployed in power modules, controllers, charging equipment, industrial electronics, inverters, energy storage units and communication devices. Without reliable potting encapsulation during continuous energized operation, filter PCBs are prone to the following failures: 1.Moisture ingress degrades insulation performance Solder points, terminals, inductors, capacitors and PCB traces on EMI filter boards are highly sensitive to humidity. Prolonged moisture penetration can cause degraded insulation, electric leakage, component corrosion and even short circuits. Waterproof & moisture-resistant potting compound forms a protective film over all electronic parts, mitigating failure risks in hot-humid operating environments. 2.Vibration and shock loosen electronic components Power equipment, industrial controllers and vehicle-mounted electronics are subject to constant vibration and mechanical impact. Tall components such as inductors and capacitors will suffer solder joint fatigue, displacement or poor electrical contact if not secured by potting resin. The…
