Updated: Dec 9, 2025 | Source: 2023-2027 Question Pool | Topic: G0B
G0B02G0B

According to the National Electrical Code, what is the minimum wire size that may be used safely for wiring with a 20-ampere circuit breaker?

Deep Dive: G0B02

The correct answer is C: AWG number 12. According to the National Electrical Code, the minimum wire size that may be used safely for wiring with a 20-ampere circuit breaker is AWG number 12. AWG 12 wire is rated for 20 amperes. For amateur radio operators, this is essential electrical safety. Understanding this helps ensure safe electrical installation.

Why Other Answers Are Wrong

Option A (AWG 20): Incorrect. AWG 20 is too small - it's rated for much less than 20 amperes. AWG 20 is too small. Option B (AWG 16): Incorrect. AWG 16 is too small - it's rated for less than 20 amperes. AWG 16 is too small. Option D (AWG 8): Incorrect. AWG 8 is larger than needed - AWG 12 is the minimum for 20 amperes. AWG 8 is larger than necessary.

Exam Tip

20A circuit breaker = minimum AWG 12 wire. Think '2'0A = '1'2 AWG. AWG 12 wire is rated for 20 amperes according to National Electrical Code. Not AWG 20, not AWG 16, not AWG 8 - just AWG 12.

Memory Aid

20A circuit breaker = minimum AWG 12 wire. Think '2'0A = '1'2 AWG. AWG 12 wire is rated for 20 amperes according to National Electrical Code. Essential electrical safety requirement.

Real-World Example

A 20-ampere circuit breaker: According to the National Electrical Code, the minimum wire size that may be used safely is AWG number 12. AWG 12 wire is rated for 20 amperes. Using smaller wire (e.g., AWG 14) would be unsafe - it could overheat. AWG 12 is the minimum safe size for 20-ampere circuits.

Source & Coverage

Question Pool: 2023-2027 Question Pool

Subelement: G0B

Reference: National Electrical Code

Key Concepts

National Electrical Code 20-ampere circuit breaker AWG number 12 Minimum wire size

Verified Content

Question from the official FCC General Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the G0B topic.