Structure of Shielded Cables

Shielded cables are composed of several layers, each serving a specific purpose to enhance performance and protect against interference. Here’s a breakdown of the typical structure of a shielded cable:

Conductor

- The core of the cable, typically made of copper or aluminum, which carries the electrical signal. Depending on the application, conductors may be single or multi-stranded for increased flexibility.

Insulation

- Surrounding the conductor is an insulating layer, usually made from materials like PVC, polyethylene, or rubber. This insulation prevents electrical shorts and protects the conductor from environmental factors.

Shielding

- This layer is crucial for blocking electromagnetic interference. Shielding can be constructed in various forms:

- Foil Shielding: A thin layer of metal foil wrapped around the insulation, effective against high-frequency interference.

- Braided Shielding: Composed of woven strands of metal, providing strong protection against EMI and RFI. It offers durability and flexibility.

- Combination Shielding: Some cables use both foil and braided shields for enhanced protection across a broad range of frequencies.

Outer Jacket

- The final protective layer, made from durable materials such as PVC, polyurethane, or thermoplastic elastomer. This jacket shields the internal components from mechanical damage, moisture, chemicals, and environmental exposure.

Grounding (Optional)

- In some shielded cable designs, there may be a grounding conductor or connection to help dissipate any interference and provide an additional layer of safety.