For 1/0 AWG copper conductors in a vertical raceway, the maximum support interval is 100 feet.

For 1/0 AWG copper conductors in a vertical raceway, the maximum support interval is 100 feet.

• A. 100 feet
• B. 50 feet
• C. 75 feet
• D. 125 feet

Answer: (A)

The main idea here is how far apart raceway supports can be for a vertical run carrying large conductors. The NEC sets a maximum distance between supports for raceways based on conductor size, to keep the raceway and the conductors protected from movement, sag, and damage. For a vertical raceway containing 1/0 AWG copper conductors, that maximum span is 100 feet. So you would place supports so no section between supports exceeds 100 feet. This allows a practical installation with fewer supports while still ensuring mechanical protection and reliability. Shorter spacings (like 50 or 75 feet) would still be acceptable but aren’t the maximum, and extending beyond 100 feet (such as 125 feet) would violate the rule for this configuration.

The main idea here is how far apart raceway supports can be for a vertical run carrying large conductors. The NEC sets a maximum distance between supports for raceways based on conductor size, to keep the raceway and the conductors protected from movement, sag, and damage. For a vertical raceway containing 1/0 AWG copper conductors, that maximum span is 100 feet. So you would place supports so no section between supports exceeds 100 feet. This allows a practical installation with fewer supports while still ensuring mechanical protection and reliability. Shorter spacings (like 50 or 75 feet) would still be acceptable but aren’t the maximum, and extending beyond 100 feet (such as 125 feet) would violate the rule for this configuration.