What is the typical overcurrent protection strategy for a 240 V residential circuit?

What is the typical overcurrent protection strategy for a 240 V residential circuit?

• A. 5 A breaker with 22 AWG conductors.
• B. 15-20 A breaker per circuit with 14 AWG for 15 A and 12 AWG for 20 A, plus grounding and GFCI/AFCI as required.
• C. 30 A breaker with 8 AWG conductors.
• D. 10 A breaker and no grounding.

Answer: (B)

Protecting a 240 V residential circuit is about matching the breaker size to the conductor’s ability to carry current safely and meeting code requirements. The standard approach is a 15- to 20-amp breaker for each circuit, with the wiring sized to support that protection: 14 AWG for a 15 A circuit and 12 AWG for a 20 A circuit. Also, circuits must be grounded, and GFCI or AFCI protection is required in locations dictated by the NEC. The option with a 5 A breaker and 22 AWG conductors would be undersized for typical loads and would trip or overheat under common use. A 30 A breaker with 8 AWG would be oversize for general residential circuits and isn’t the typical protection for standard outlets and lighting. A 10 A breaker with no grounding is unsafe and noncompliant. Therefore, the 15–20 A protection with appropriately sized conductors, plus grounding and GFCI/AFCI where required, is the correct strategy.

Protecting a 240 V residential circuit is about matching the breaker size to the conductor’s ability to carry current safely and meeting code requirements. The standard approach is a 15- to 20-amp breaker for each circuit, with the wiring sized to support that protection: 14 AWG for a 15 A circuit and 12 AWG for a 20 A circuit. Also, circuits must be grounded, and GFCI or AFCI protection is required in locations dictated by the NEC. The option with a 5 A breaker and 22 AWG conductors would be undersized for typical loads and would trip or overheat under common use. A 30 A breaker with 8 AWG would be oversize for general residential circuits and isn’t the typical protection for standard outlets and lighting. A 10 A breaker with no grounding is unsafe and noncompliant. Therefore, the 15–20 A protection with appropriately sized conductors, plus grounding and GFCI/AFCI where required, is the correct strategy.