Page 54 - 2021 Connectivity Components: Everything but the Connectors eBook

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Beyond the Basics: Component Modification and Customization
Ken Horlacher, DC Solutions Engineering and Market Development Manager, Phoenix Contact USA
The quality of the connection points can be one of the most important aspects of electronic device design. It is critical to strategically select reliable, application-specific connectors to help eliminate performance failures or potential installation issues. The proper connector can provide quality and peace of mind, with reassurance that there will not be faults in the field. It can also reduce manufacturing costs and make wiring easier. Yet, in many instances, connectivity is the last item addressed.
In today’s cost-competitive landscape, there is a tendency to make cost the primary driver of connector selection. While cost obviously needs to be taken into consideration, it is also important to understand the quality of the materials and construction of the connector in relation to its cost. This will ensure connectivity reliability during the device’s lifetime.
Also, when comparing connectors from different manufacturers, make sure to compare apples to apples. Subtle material or component differences can impact the overall quality of the connector and the cost. Examining the various basic attributes of the connector is a good place to start.
Connector housing
Many different materials can be chosen for connector housing. Consider these key factors: operating environment, temperature exposure, flammability ratings, and the manufacturing process being used (such as wave solder, SMT, and pin-in-paste).
A simple, good example would be a PCB-mounted terminal block for an industrial application. In this instance, quality manufacturers will typically use a nylon material like polyamide. Benefits of a material such as this include V0 flammability rating, high tensile strength, recyclability, operating temperatures up to 125° C, excellent aging characteristics, high chemical resistance, and high strength.
Metal components
The metal components of the connector encompass the pins, sockets, contacts, and clamping mechanisms. Similar to the available plastics that can be used for the connector housing, the options for metal materials are vast. For the same PCB-mounted terminal block mentioned above, consider a screw-clamping mechanism with PCB pins to be wave-soldered to the board.
In this instance, a plated copper alloy is an excellent choice for the PCB solder-pin due to its strength, ability to withstand corrosion, excellent electrical conductivity, and thermal properties. For the clamping mechanism, consider the metals that would be the best fit for this application. In this particular connector, the use of a copper alloy is logical because the use of similar metals reduces corrosion and maintains a consistent, quality connection. Additionally, different metals expand and contract at different rates with temperature changes. Using the same metals for components that will interact within a circuit ensures a quality contact throughout the connector’s use.
It’s all in the details
After examining the basic characteristics of the components that make up a connector, the next step is to identify potential enhancements to these basic material choices, as well as the value-added services that support the application requirements. Specific requirements for the application environment, potential standards, and the manufacturing process all impact the choice of plastic housing material.