Which of the following statements best reflects EMI-reduction guidance?

Which of the following statements best reflects EMI-reduction guidance?

• A. place low-voltage cables near power conductors
• B. use grounded metal pathways
• C. avoid barriers between circuits
• D. use shielded power conductors only

Answer: (B)

Grounded metal pathways act as a shield and a low-impedance return path, which is the most effective way to suppress EMI in a cabling system. When these metal routes, like cable trays or conduits, are continuously bonded to earth, they contain and drain unwanted noise, reducing both radiated interference and conducted noise. That solid grounding keeps the signal reference stable, minimizes loop areas where EMI currents can form, and makes it harder for external noise to couple into or out of the cables. The other ideas either invite more coupling or fail to provide a robust shield. Putting low-voltage cables next to power conductors increases exposure to the power system’s fields, boosting EMI. Removing barriers between circuits weakens isolation and lets noise travel more readily between them. Requiring shielded power conductors only misses the broader protection that comes from properly grounding and shielding the pathways themselves, which is why grounded metal pathways is the strongest guidance for EMI reduction.

Grounded metal pathways act as a shield and a low-impedance return path, which is the most effective way to suppress EMI in a cabling system. When these metal routes, like cable trays or conduits, are continuously bonded to earth, they contain and drain unwanted noise, reducing both radiated interference and conducted noise. That solid grounding keeps the signal reference stable, minimizes loop areas where EMI currents can form, and makes it harder for external noise to couple into or out of the cables.

The other ideas either invite more coupling or fail to provide a robust shield. Putting low-voltage cables next to power conductors increases exposure to the power system’s fields, boosting EMI. Removing barriers between circuits weakens isolation and lets noise travel more readily between them. Requiring shielded power conductors only misses the broader protection that comes from properly grounding and shielding the pathways themselves, which is why grounded metal pathways is the strongest guidance for EMI reduction.