Belden Essential Cable Facts: Electromagnetic Interference

Patented Belden shielding innovation: Z-Fold

Belden Z-Fold technology video [0:34]

These are patented techniques that close gaps in the shield and give maximum protection against interference.


Cables interfering with one another can seriously undermine data transmissions and control in industrial automation. Are you aware that many cables on the market today have not been designed to sufficiently prevent signal leakage and interference?

What cable components are critical?

When it comes to electromagnetic interference the key component is:

  • The shield (or screen) is a physical barrier that protects the signals and electrical energy passing through the conductor from external interference. It can also prevent the cable itself from being a source of interference.

What is the threat of electromagnetic interference?

Electromagnetic interference threatens reliable and consistent signal performance. The shield design and type of shielding materials used in a cable determine the level of protection against external interference and against emissions from the cable itself. Poor shield design, particularly in the case of a foil shield without a shorting fold, can leave gaps through which signals can leak, or be disturbed.

What is the effect of electromagnetic interference on sub-standard cable?

  • Exposing a cable with an ineffective shield to an environment with high external interference will reduce its performance.  
  • Insufficient shielding can also result in alien crosstalk or cable-to-cable interference. Such interference can cause disruption to the signal transmission.

What risks does this pose to a building or system?

  • System latency or downtime: failure of a cable due to external interference or cross talk can lead to expensive system latency of even downtime.
  • Safety risk: in the case of monitoring, CCTV and security systems unreliable signal performance can lead to unacceptable security risks.