Electrolube polyurethane resin is the material of choice for demanding sensor application.

The sensor''s electronics, in the form of a small printed circuit board (PCB) contained within the unit, had not only to be protected from adverse atmospheric conditions, but also meet certain requirements posed by the hazardous nature of the sensor location. Based on these operating conditions, Electrolube was tasked with selecting an appropriate resin for the PCB.

Resin systems are designed to protect and insulate PCBs and electronic components from the threats of harsh and challenging environments, including moisture, mechanical vibration, thermal or physical shock and general contamination. By encapsulating the entire device, resins can form a complete barrier against such environments offering superior performance under extreme conditions.

As this sensor was to be tested for use in hazardous locations, a UL approved resin was deemed essential. Moreover, the chosen resin had to withstand salt mist, occasional contact with chemicals and temperatures frequently dipping below 0°C, but not exceeding 60°C.

Following an appraisal of the customer''s specifications, Electrolube suggested that its two-part, high performance polyurethane resin UR5604 would comprehensively meet the needs of this application, thanks to its excellent all round protection, even at temperature extremes. Of particular note is the resin''s post-cure flexibility, which ensures minimal stress on the PCB components resulting from temperature fluctuations. In addition, UR5604 offers the highest classification of flame retardancy: UL94 V-0.

Applying UR5604 resin couldn''t be easier; it offers low mixed system viscosity, ensuring a fast and efficient potting process, and the RoHS compliant (2011/65/EU) product provides excellent adhesion to a wide variety of substrates. With a cured system temperature range of -40°C to +130°C, the resin more than meets the operating temperature range specification for this sensor application.

Electrolube''s encapsulation resins are available in epoxy, polyurethane and silicone formulations with specific properties designed to protect and insulate printed circuit boards (PCBs) and electronic components from the threats of harsh and challenging environments.