High glow-wire resistance
key arguments for using our material in this application were its high tracking
resistance and high flame-retardance based on the halogen-free flame retardant
package. It is also easy to process and produces components with a high surface
quality,” explains Dr. Bernhard Helbich, Technical Marketing Manager Key
Accounts at Lanxess. The compound’s level of flame-retardance is demonstrated
by the UL 94 flammability test of the US Underwriters Laboratories Inc. testing
organization. The polyamide passes the test with the top classification of V-0
at a test specimen thickness of 0.75 millimeters.
wallboxes come under “unattended household appliances”, the plastics used must
comply with the international standard IEC/EN 60335-1. In particular, they must
prove that they are flame-retardant in glow-wire testing. Durethan BKV20FN01
passes the GWIT test (Glow Wire Ignition Temperature, IEC 60695-2-13) at 775 °C
with test specimen thicknesses of 0.75 millimeter and above. In the GWFI test
(Glow Wire Flammability Index, IEC 60695-2-12), the thermoplastic achieves the
top value for plastics of 960 °C (0.75 millimeter test specimen thickness).
Reduced risk of short circuits and equipment
strength of the material is its high tracking resistance. For example, it
achieves the top rating of 600 in the CTI A test (Comparative Tracking Index,
IEC 60112) and the top value of PLC 0 (Performance Level Category) in the similarly
designed UL 746 test. “This reduces the risk of short circuits and defects
caused by creepage currents in the wallbox. In addition, the electrical and
electronic assemblies can be designed more compactly, resulting in a smaller
device overall with higher power density,” Helbich explains.
compound, which is reinforced with 18% short glass fibers by weight, also has
good strength, stiffness and toughness. The charging cable connector systems
are therefore not susceptible to mechanical loads, particularly during
assembly. The polyamide can also be economically processed in a stable
injection molding process.