We live in an increasingly connected world, and despite the advantages of technologies like the Internet of Things (IoT), such innovations don’t come without challenges. For example, globally, there are over 26.66 billion connected devices that send signals back and forth over long distances. All of these device-to-device communications (in addition to other natural and human-made sources) increase the presence of electromagnetic energy all around us. This electromagnetic energy can disrupt the flow of electricity in cables and connectors, resulting in potentially serious problems, such as data loss or total power failure.
By 2022, the number of connected devices is expected to increase by another 15.96 billion, which makes cable shielding one of the most important design elements in new product development.
What is shielding?
Shielding is a protective layer of material (usually copper or aluminum) that is built into a cable or connector to deflect electromagnetic interferences and to prevent the cable from emitting electromagnetic energy that could disrupt other systems.
There are two main types of shielding:
- Braided shielding: strands of copper or aluminum wire braided together to form a tubular or flattened mesh that encloses a conductor or cable core and provides about 80% to 95% coverage (depending on how tightly the wire is braided).
- Foil tape shielding: a laminate of aluminum or copper and polyester layers with an adhesive backing that can be wrapped around a conductor or cable core to provide 100% coverage.
The shielding material is sheathed in a protective layer called a cable jacket, which can be custom-engineered using a variety of different materials, such as PVC, PE, PUR, and TPR/TPE to meet specific performance demands, such as resistance to fire or extreme temperatures.
Which type of shielding is right for you?
Now that we’ve answered the question, What is shielding? Let’s discuss how to choose the right type of shielding for your application. Start by answering the following questions:
- Do you have any significant time or budget constraints?
- Are there any spatial limitations involved in the electrical configuration?
- How will electrical components be utilized in the field?
- What type of interference is likely to occur in the application environment?
- Though often used interchangeably, there are two different types of interference:
Electromagnetic Interference (EMI): The disruption of a signal due to the emission of electromagnetic energy from all natural and human-made sources (high, medium, and low frequencies). For example, large motors, transformers, radiation, etc.- Radio Frequency Interference (RFI): The disruption of a signal due to the emission of electromagnetic energy that specifically comes from the low-frequency side of the electromagnetic spectrum. For example, wireless devices, microwaves, fluorescent lightbulbs, etc.
Once you define the nature of your application, cost, timeline, and type of interference, look at distinguishing factors for each type of shielding to determine which makes the most sense for your project.
Braided Shielding Key Points:
✓ Best fit for RFI
✓ Protects from low and medium frequencies
✓ Excellent flexibility
✓ Excellent mechanical strength
✓ More costly than foil tape
✓ Requires more time to manufacture
✓ Bulky and heavy (not ideal for micro-products)
✓ Can be terminated (may require a drain wire)
Foil Tape Shielding Key Points
✓ Best for EMI
✓ Protects from all frequencies (especially high range)
✓ Thin and lightweight
✓ Ideal for micro-products and tight spaces
✓ Poor flex life
✓ Little or no mechanical strength
✓ Inexpensive/quick to manufacture
✓ Limited termination options
If you still aren’t sure which type of shielding is best for your application, contact the experts at iCONN Systems. Our experienced product development team will help you select a solution that meets the exact demands of your application, including custom engineering and agile manufacturing at scale.
For more information, download our free whitepaper: Maintaining EMI/RFI Shielding in Electrical Connectors.
