Lumberg Inc. has introduced a line of RAST 2.5 and 5.0 connectors that have passed the European “glow wire” standard for flammability. The standard states that a product must be able to reach 750°C without breaking into a flame. The connectors have a range of applications, including white goods, consumer electronics, small electric appliances, and floor care appliances.
In order to meet the glow wire standards, the company needed to change the material of the connectors. “Standard materials that have been used for many years are, with some exceptions, not able to meet the requirements of IEC 60335-1,” explains Stefan Joergens, R&D engineer/manager for Electronic Products. “Additionally, the higher soldering temperature of a lead-free soldering process requires sourcing of new raw materials for production that have never been used.”
Choosing flame-resistant plastic materials required Lumberg to work closely with material suppliers. The company also took into account Europe’s lead-free initiative mandated by RoHS, the European directive that reduces the amount of hazardous materials used in electronics.
Lumberg also ran a set of tests for the new connectors, including a descending curve test, current capacity, insertion and withdrawal force testing, vibration testing, and shock testing. Working in cooperation with the plastic materials suppliers and extensive analysis of test results led Lumberg to choose a new polyamide material, which can withstand higher temperature and is flame-resistant.
“RAST connectors from Lumberg fulfill all national and international standards, as well as UL, VDE approvals, and lead-free requirements,” Mr. Joergens tells APPLIANCE. “Therefore, they are ‘green,’ environmentally safe components, which the consumer can feel safe using.”
Improved reliability is one of the performance advantages offered by the new connectors. According to Mr. Joergens, connectors with individual contacts increase the possibility of a wrong connection. The new RAST connector, however, uses a multi-contact connector in combination with a multi-contact header on the edge of the circuit board.
The new connectors with double-sided keying have 15 different keying options as opposed to the old design, which only offered six for a two-pole connector. This allows multiple connectors to be attached next to each other on the same circuit board. For example, if several two-pole headers are placed next to each other, then the keys in the headers will only allow the correct, associated connector to be placed in these headers.
The connectors can also be used with different wire materials such as silicon insulation, TPE-insulation, enameled wires, solid wires, and stranded wires. Both the RAST 2.5 Power and the RAST 5.0 can handle a current of 10 A and are suited for high-volume, high-speed production.