2023 240.4 Protection of Conductors

Adjustable trip circuit breakers were clarified, 10A circuits with 14 AWG copper-clad aluminum conductors are addressed, and dwelling unit feeders and services are now mentioned here.

[@pierrebelarge892]

Ryan, well done some great information here that is not always easy to get in the field. Thanks!

[@phillipyangmusic]

Thank you for another Awesome Video!

[@victorco.6308]

thank you

[@josemancia3689]

Thanks master I will check all the videos 1 by 1 ,- can we use a 12/2 on a 15 breakers and then from a junction box continue the circuit with 14/2 to add small loads ? Or it’s a code violation ?

[@chrisf3875]

Hello from Massachustts😁
Looking for your help to clarify my underestand of 240.4 (b)(1)
How do we view....conductors,not part of a branch ciruit?
Are Feeders(being conductors) supplying a main lug panel that serves only branch ciruit loads allowed here? Or are they part of the Branch Ciruits in some way, is this rule for more like feeding a CNC Machine or some other utilization equipment.
Example.
I have a generator with a 2 pole 90 amp breaker feeding a transfer switch that serves the house panel. Using #4 copper THWN at 75 degrees Celsius, Bing my terminations are rated for 75 degrees Celsius. Table 310.16 says # 4 wire is good for 85 amps. I do believe I could use this now for 90 amps under this allowance, curious to see if you're in agreeance with me or I'm misusing this allowance.
Thanks

[@RyanJacksonElectrical]

That is only for branch circuits. For feeders we can ignore 240.4(B)(1)

[@chrisf3875]

Got it, so feeders are allowed to be upsize to the next standard rating overcurrent device. Under 240.4 (B).
When you say ignore You're actually stating The feeders are not part of the branch circuits in the panel that it feeds. And some strange twist of the six degree of separation thought 😅.

[@smartmoney.education]

I am wondering why article NEC 334.80 was not mentioned in the video. Because it states: "The ampacity of Types NM and NMC cable shall not exceed that of a 60 degree rated conductor" Which limits NM cables (aka romex) even with sizes bigger than 10AWG to 60 degree column only when choosing ampacity.
With that in mind even though we have termination points rated at 75 degrees using any big size romex we are still limited to 60 degree ampacity ratings. Or I am missing something???

[@RyanJacksonElectrical]

It wasn't mentioned because that wasn't the topic of the video. The video is covering 240.4. I have videos that cover ARtciel 334, and particularly section 334.80, but this isn't one of them.

[@smartmoney.education]

@RyanJacksonElectrical thank you for clarification, sir. I really appreciate the work you do for us electricians creating the content 🙏🏻

[@RyanJacksonElectrical]

@@smartmoney.education You're welcome. :)