What should be the minimum size for conductors feeding a 20-amp circuit?

The minimum size for conductors feeding a 20-amp circuit is 12 AWG (American Wire Gauge). The National Electrical Code (NEC) provides guidelines that specify the appropriate conductor sizes based on the circuit's amperage. For a 20-amp circuit, 12 AWG is designed to handle the current without exceeding its temperature rating, ensuring safe operation and minimizing the risk of overheating, which can lead to electrical fires.

Using 12 AWG is essential because it provides adequate conductivity while also allowing for some degree of derating in cases where multiple conductors may be bundled together or when the circuit operates in high-temperature environments. This ensures not only the safety of the circuit but also the reliability of the electrical system for its intended use.

While smaller gauge wires like 14 AWG may function under certain conditions, they are rated for only up to 15 amps. Using them in a 20-amp circuit would not comply with electrical code requirements, leading to potential safety risks. Similarly, 10 AWG and 16 AWG wires are either oversized for this specific application or too small, respectively, making 12 AWG the correct and safe choice for a 20-amp circuit.