The German Association for Electrical, Electronic and Information Technologies (VDE) has certified six halogen-free, flame-retardant BASF polyamides for use in compliance with the household appliance standard, which has recently been made stricter. As a result, BASF is the plastics manufacturer that can currently offer its customers the most comprehensive product line of engineering plastics intended specifically for electrical applications in unattended household appliances according to IEC 60335-1, without the need for additional approvals.
Six certified halogen-free, flame-retardant Ultramid grades
Since early 2007, the VDE has been making it easier to comply with the new household appliance standard IEC 60335-1 by issuing material-specific certificates. In the meantime, six different halogen-free, flame-retardant polyamides (PA) made by BASF have been completely tested and certified for use in household appliances that fall under standard IEC 60335-1.
Ultramid A3X4G7: halogen-free, cost-effective and approved for several wall thicknesses
Among the six recently certified polyamide types, special mention should be made of Ultramid® A3X4G7. This PA 66, reinforced with 35% glass fibers (GF), has been tested and approved by the VDE not only for the wall thicknesses of 1.0 mm, 2.0 mm and 3.0 mm, but also for 0.6 mm. “Moreover, this halogen-free material, which has been rendered flame-retardant with red phosphorus, is even cheaper than polyamides containing halogen and only 25% GF because, in spite of its higher glass fiber content, it weighs less,” explains Jochen Seubert, project engineer working in the realm of BASF’s flame-retardant engineering plastics. The other BASF materials certified by the VDE include the non-reinforced polyamides Ultramid B3S (PA6) and Ultramid C3U (PA6/66), the two PA 66 types Ultramid A3K and Ultramid A3W as well as the reinforced PA 66 Ultramid A3UG5. The approval certificates can be obtained from the hotline [email protected]
New VDE test certificates for plastics – advantages for customers
Thanks to the VDE test certificates, the standard IEC 60335-1 can now be met through the modality of material testing. In other words, already when pre-selecting the material, customers can choose a plastic that is approved for electrical use in these specific household appliances. They can save many tests and development steps since they have the assurance of working with materials that comply with the standards. Seeing that the VDE monitors the certifications, users can also count on a great deal of reliability when it comes to serial production. And the fact should not be overlooked that this greatly simplifies the final testing of the finished appliance for purposes of obtaining the VDE mark. If the customer is already employing a VDE-certified plastic, the glow-wire tests on the individual device components can be dispensed with.
What is tested? Expanded household appliance standard IEC 60335-1
Standard IEC 60335-1 relates, among others, to household appliances which operate unattended and through which high currents flow (more than 0.2 A) such as washing machines, ovens and even electric motors in exhaust hoods. A plastic employed in the immediate vicinity of current-carrying parts is considered to be in compliance with IEC 60335-1 if test platelets made of the plastic pass the flammability test (GWFI: glow-wire flammability index) at 850°C [1562°F] and the ignitability test (GWIT: glow-wire ignition temperature) at 750°C [1382°F], (formally called: “GWIT 775”). The VDE now issues certificates for plastics that it has subjected to these glow-wire tests on plate-like test specimens. Such VDE-certified plastics meet the requirements of standard IEC 60335-1.