In an emergency, rapid shutdown boxes switch off photovoltaic (PV) modules or strings in a controlled manner within a very short time, thus protecting rescue services from exposure to hazardous voltages. They also ensure the safety of employees during maintenance work. The safety-related electronic components must be able to withstand not only environmental impacts, but also mechanical and thermal stresses on a permanent basis. The WEVOPUR 512 FLE electronic potting resin developed by WEVO-CHEMIE GmbH is a proven solution for the long-term functionality of these boxes. The properties of the low-viscosity polyurethane potting compound include high corrosion resistance, permanent elasticity, a low thermal expansion coefficient and good thermal conductivity.
Safety requirements for PV systems are becoming increasingly stringent worldwide, which means that shutdown devices for swiftly reducing voltage are gaining in importance. In the USA, rapid shutdown is already mandatory and governed by the National Electrical Code (NEC). WEVOPUR 512 FLE has been optimised for use with the electronic components required in these systems; the thermally conductive PU potting compound enables energy technology manufacturers to develop shutdown boxes that meet the rigorous North American standards and are therefore broadly accepted worldwide.
Optimised material properties for safe operation
Wevo has optimised the electronic potting resin in terms of several key properties:
- Permanent bonding with the housing: The potting compound reliably protects electronic components from moisture and mechanical stress.
- Targeted thermal management: WEVOPUR 512 FLE safely and reliably dissipates the heat generated during operation.
- High corrosion resistance: The specially developed formulation prevents electrochemical corrosion from forming on the printed circuit boards used – the protective effect has been scientifically verified by the Technical University of Denmark.
- Good temperature resistance: The combination of low expansion coefficient and elastic properties effectively compensates for stresses caused by temperature fluctuations.
WEVOPUR 512 FLE complies with all international norms, standards and safety requirements. The polyurethane potting compound is certified in accordance with UL 94 V-0 at 6 mm and V-2 at 1.5 mm, enabling flexible designs for electronic components. Moreover, the 2K polyurethane system is PFAS- and TPP/TEP-free (SVHC-compliant).
Polyurethane potting for efficient series production
The processing properties are designed for efficient series production, the pot life of just a few minutes guarantees short cycle times. The product’s excellent flow and wetting properties ensure that electronic components such as printed circuit boards are reliably encapsulated, reducing the risk of air pockets forming. As a result, the manufacturing process can be carried out without an additional evacuation step after potting – a distinct advantage in terms of process reliability, throughput and cost-effectiveness.
Further applications in modern electronics
In addition to its use as a polyurethane potting compound for shutdown boxes in PV systems, WEVOPUR 512 FLE is also suitable for battery systems and battery packs for power tools, as well as for transformers, capacitors and sensors. The combination of good heat dissipation, corrosion protection and reliable processing makes the electronic potting resin a versatile solution for high-performance electronics.
- Polyurethane potting with WEVOPUR 512 FLE ensures long-term functionality of rapid shutdown boxes in PV systems.
- Optimised properties for safe operation and efficient production: durable elasticity, low thermal expansion coefficient, good thermal conductivity, low viscosity.
- Compliant with international standards: certified according to UL 94 V-0/V-2, PFAS- and SVHC-compliant.
- Result: Protection against moisture, high temperatures, corrosion and mechanical stresses.
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