No, a 6/3 NM cable cannot be protected by a 60 amp overcurrent protective device (OCPD) in a residential feeder application according to the 2023 NEC. Here's why: Ampacity of 6/3 NM

NM cable ampacity is determined by NEC Table 310.16 and then further limited by 334.
80. 6 AWG copper NM cable has an ampacity of 55 amps when operating at 60°C

NEC 334.80 Ampacity

Nonmetallic-sheathed cable (NM) can only be used at the 60°C (140°F) ampacity rating which, for 6 AWG copper, is 55 amps.

Overcurrent Protection Limitation

NEC 240.4(D)(4) states that overcurrent protection shall not exceed 55 amps for 6 AWG copper conductors unless specific exceptions apply.

Therefore, you cannot use a 60 amp breaker to protect a 6/3 NM cable because the cable is only rated for 55 amps.Acceptable Overcurrent Protection

The maximum overcurrent protection you can use for 6/3 NM is a

50 amp breaker.

Important Considerations



Feeder Demand Load

The calculation of the feeder demand load must be determined per Article 220. The OCPD is selected to protect the conductors not exceed the ampacity rating of the conductors.

Appliance Branch Circuits

If you have individual branch circuits with specific appliance requirements, those will be determined by 210.19.

Disclaimer: This information is for general guidance only and does not constitute professional electrical advice. Always consult with a qualified and licensed electrician for accurate and safe electrical installations that comply with all applicable codes and regulations. Flag for review