Epec's Blog | Electronics Manufacturing Solutions

When we think of manufacturing in the 21st Century, we picture automated machines rapidly pumping out new products with ease. So why can't the process of complex wire harness manufacturing become fully automated as well? To answer this question, we need a deeper understanding of cable harnesses and how they are prepared.

A cable harness, also referred to as a wire harness, cable assembly, wiring assembly, or wire loom, is a grouping of wires and/or cables that are used to transmit signals as well as provide electrical power if needed. The wires and cables are joined together using a combination of straps, cable ties, cable lacing, tubing (either shrink tubing or non-shrink tubing), sleeving, electrical tape, conduit, and braided extruded string.

Cable pre-molding, sometimes associated with potting or encapsulation, is used to protect the termination points from the surrounding environment.  Pre-molding involves the application of a material around the back section of a connector where the termination points are located.

The major difference between a stranded cable and solid cable is the flexibility. Within this post we will define cable flexibility with regard to ability to withstand continuous movement. Depending on your application, cable flexibility can be a factor when choosing the proper components for your cable assembly or wire harness.

The need to protect your keypad from the ever-present threat of wear-and-tear is crucial for all applications. If your control panel is going to be used in marine environments, medical devices, or other consumer electronics, the threat of water or liquid exposure is ever present. In wet situations, it is critical that all electronic components are completely sealed off from any outside substances that could damage the device.

Many applications would be better suited using a membrane switch (low profile, flat surface keypad assembly) along with a rigid printed circuit board (PCB), replacing screen-printed silver conductors on polyester sheets.

Printed circuit boards with gold plated switch contact pads and gold-plated dome switches greatly improve the reliability of your application, offering longer operating life with lower switch resistance and contact bounce.

The smallest bend radius that can be used on a membrane switch tail will depend on the type of design. Deciding factors will depend on whether or not the user interface is constructed with one tail/circuit layer or dual tail/circuit layers, and where the bend is located.

Overmolded cables are full assemblies that seamlessly combine the wire and the connector into a single part. The process of overmolding a cable involves injecting a molten material into a mold cavity, which conforms to the desired shape when cooled. The mold cavity can be built as a simple design with no markings or as a more complex design if you wanted to include a company name, corporate logo, flanges to be used as attachment points, or an extended strain relief area.

Custom low-profile keypad assemblies used in OEM applications incorporate snap-acting dome switches. Dome switches are a type of keypad assembly switch intended for very long cycle life and years of trouble-free use but are intended for logic-level switching, not power switching.