According to NEC, the minimum wire size for class 3 circuits is what gauge?

The National Electrical Code (NEC) specifies a minimum wire size for Class 3 circuits to ensure safe and effective operation of low-voltage systems. Class 3 circuits are designed to operate at a maximum voltage of 60 volts and are used in a variety of low-voltage applications including communications and control systems.

The minimum wire gauge for these circuits is 18 AWG (American Wire Gauge). This specification is crucial because it ensures that the wire can safely carry the current without overheating, while also allowing for flexibility and ease of installation. Using wire that is too small can lead to increased resistance, which may cause voltage drop issues and potentially lead to system failure or fire hazards.

In summary, the correct answer identifies 18 AWG as the minimum size for Class 3 circuits as outlined in the NEC, reflecting the balance of safety and performance required in low-voltage installations.