NEC Commercial Electrical Practice Test

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Prepare for the NEC Commercial Electrical Test with multiple choice questions each with detailed explanations. Study efficiently to excel in your exam!

Practice this question and more.

When securing non-metallic cables, what is the maximum interval allowed between supports?

3 ft
4 ft
6 ft
5 ft

The correct answer is: 4 ft

When securing non-metallic cables, the National Electrical Code (NEC) specifies that the maximum distance between supports is 4 feet. This requirement ensures that non-metallic cables, such as NM (non-metallic) cable, are properly secured to prevent sagging, damage, or unnecessary strain on the conductors within the cable. The 4-foot support interval helps maintain the integrity of the installation and protects the cables from physical stress. Additionally, it is important for ensuring that the installation meets electrical safety standards, reducing the risk of electrical faults and fire hazards associated with improperly secured wiring. Cables that are not secured at appropriate intervals could lead to issues such as increased wear and tear, exposure to environmental factors, or compliance failures during inspections. Hence, adhering to the 4-foot support rule is critical in both residential and commercial wiring applications.