Question T0A09
From subelement T0 - T0A
What should be done to all external ground rods or earth connections?
Why is this correct?
All external ground rods must be bonded together with heavy wire or conductive strap to create a unified grounding system. This ensures lightning energy finds a direct path to ground instead of traveling through equipment seeking alternative routes. Option A (waterproofing) is unnecessary since ground connections are designed to be underground. Option B (keeping apart) creates multiple isolated grounds that can develop dangerous voltage differences. Option D (tuning for resonance) is irrelevant for safety grounding systems.
Memory tip
Remember the key principle: 'One building, one ground system.' Multiple isolated grounds create voltage differences that can damage equipment or cause safety hazards. Always think 'bonding' when you see grounding questions—electrical systems work best when everything shares the same reference point to earth.
Learn more
This bonding requirement stems from NEC Article 250, which mandates that all grounding electrodes at a premises be bonded together to form a grounding electrode system. In amateur radio installations, this prevents ground loops and ensures that lightning energy or fault currents have a consistent, low-impedance path to earth. The heavy wire or conductive strap must be capable of carrying fault current safely, which is why materials like #6 AWG copper wire or copper strap are commonly specified in electrical codes.
Think about it
Why do you think having multiple unbonded ground rods could actually create a safety hazard rather than providing better protection?