Secondary SPD bonding for telco, data, and control circuits shall be bonded using which gauge/length options?

• A. #10 AWG not exceeding 3 ft
• B. #6 AWG not exceeding 13 ft
• C. Both A and B
• D. Neither A nor B

Answer: (C)

Establishing a low-impedance secondary bonding path for surge protective devices on telco, data, and control circuits is the key idea here. The bonding conductor from the SPD to the grounding system must remain effective enough to carry surge energy without adding significant impedance, so both size-and-length options are allowed because they achieve that goal in different ways.

Using a smaller conductor, like #10 AWG, is acceptable if the run is very short (not exceeding 3 ft) to keep resistance and reactance minimal. If a longer run is needed, a larger conductor (like #6 AWG) can be used, up to a length of 13 ft, because the thicker wire provides a lower impedance path, compensating for the extra distance. In both cases, the aim is the same: ensure a fast, direct path for surge energy to reach the ground, protecting the equipment on the circuits.

So both options meet the requirement, offering flexibility to balance practical installation constraints with the electrical impedance needs of the SPD bonding path.