Plastics provide more cost-efficient route to safer circuit breakers

Paul Boughton

Royal DSM is the first engineering plastics supplier to offer a full portfolio of materials that can replace thermosets in demanding moulded-case circuit breakers (MCCBs) with open arc extinguishing chambers. Jiangsu Phono Electrical Co Ltd is the first company to use Stanyl in an arc chamber for MCCBs.

Suppliers of electrical goods want to cut costs while retaining the highest quality and safety. They are becoming more global in their operations, but they still need local capabilities to meet their local needs—a trend that is being driven not only by consumers but also by the need to conform to local regulations, national standards and building codes, and local content incentives. DSM, having regional technical centres around the world, is in a strong position to address these trends.

DSM has been a pioneer in replacing thermosets in low voltage switchgear (LVSG) applications such as miniature circuit breakers (MCBs) for over 35 years. Now, with its most recent developments, the company has a proven portfolio of engineering plastics and support services that will enable material substitution in MCCBs, which are far more demanding in their technical requirements.

MCCB are heavy duty circuit breakers, mostly used in industrial and commercial applications, operating at far higher electrical ratings than residential circuit breakers. They comprise a large moulded box that isolates the electrical paths and contains a safety mechanism that protects downstream equipment from overloads. Use of MCCBs is increasing, due to the growing need for energy conservation through electronic regulation of large area electrical networks.

The DSM portfolio now encompasses such advanced materials as the Stanyl polyamide 46 range—including Stanyl CR new-generation, halogen-free UL94 V-0 flame retardant types—as well as new halogen-free FR grades of Akulon polyamide 6 and 66. This portfolio enables DSM customers to produce parts with improved electrical endurance, enhanced aesthetics and reduced wall thicknesses compared with parts made in traditional thermoset compounds.

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