Which statement about shielding and bonding is true?

• A. Shielding increases EMI susceptibility.
• B. Shielding reduces EMI when properly grounded; bonding establishes a common ground.
• C. Bonding is only required for underground cables.
• D. Shielding is unnecessary in most irrigation systems.

Answer: (B)

Shielding and bonding work together to minimize interference and ensure safety in irrigation wiring. Shielding involves wrapping conductors in a conductive layer that can intercept electromagnetic interference. When that shield is properly grounded, the interference is diverted to ground rather than into the signal lines, so sensors and controllers see less noise and operate more reliably.

Bonding ties all metal parts to a single, common ground point. This eliminates voltage differences between components that could drive stray currents or noise, improving both safety and signal integrity.

The statement is true because proper grounding is essential for shielding to be effective and because bonding creates the shared ground reference needed to prevent potential differences across the system. In contrast, shielding does not increase EMI; and bonding is not limited to underground cables, while shielding is not typically deemed unnecessary in irrigation systems where EMI sources can exist.