Fuse board upgrade with consumer unit circuit breakers.

Conductors and Overcurrent Protection, 2023 NEC

Code Hunter
Code Hunter

Ready to take a quiz that tests your knowledge on wiring and protection in the NEC? | Spring 2023 issue

1. What is the ampacity of 12 AWG THHN conductors installed at an ambient temperature of 80°F with three conductors in a raceway?


2. Article 240 does not allow __________ to be reconditioned.


3. If selective coordination of feeder overcurrent devices is required, they must also selectively coordinate with the __________ overcurrent device(s).


4. The minimum size copper conductor for general applications of 2000V and less is __________.


5. Overcurrent devices are not allowed in _________.


6. Which of these conductors are permitted in a wet location?


7. What is the minimum allowable interrupting rating for a branch-circuit overcurrent protection device?


8. Which of the following is a permitted method for restricting access to the adjustments of a circuit breaker?


9. Type __________ conductors are only permitted for switchboard and switchgear wiring.


10. Circuit breakers must be __________ free and capable of being manually opened and closed.


11. True or false? A circuit breaker with a slash rating, such as 120/240 or 480Y/277V is allowed on an ungrounded system.


Christel Hunter
Christel Hunter is vice president of engineering for Cerro Wire. Chris is a senior associate member of IAEI and serves as President for the Southern Nevada Chapter of IAEI. Chris also serves on NEC CMP-6 and CMP-13, NFPA 921, NFPA 70B, NFPA 73 and UL STPs 62, 83, 719 and 4703. Chris is a Certified Standards Professional, Master Electrician, and LEED Accredited Professional.