Excellent video! @23:00 I just use the inverse of the adjustment factors and multiply. 1/0.71=1.408; 1/0.8= 1.25. For a 50A circuit we will need 50 x 1.408 x 1.25 = we need a conductor rated for 88A. From Table 310.15 B 16 #4 AWG is rated for 95 A which is slightly more than the required 88A.
is this 2023 nec? the only issue i’m having studying is these temp factors. the guy who made the exam buster sent me a nasty email when i asked him a question. so here i am trying to self teach
If the question is asking you to derate based only on the temperature (above 86 degrees F), do you still always start with the ampacity from the 90 degree column? Are there any instances that you "start a math problem" using the ampacities from the 75 or 60 degree rated columns? obviously it changes your answer if you start with the ampacity from the wrong column.
Hi, the book being referenced in this video is NFPA 70: The national electrical code, 2022 edition. I am not sure how ordering things online/shipping works in the Philippines, but the book is available on NFPA's website. Hope that helps!
on the last question where you gave 50 amp , 6 ccc and 140 degree. I started in the 90 degree col with a #8. You did something different and i dont understand why?
i think he was showing that there are correction factors and adjustments factors that will not change, so if you are a bit lost you could put in different ampacities using the same math till you find a answer on the test......im not 100% sure but i had the same problem as you can that was my best guess. Did you end up with 31.24 and next size up of 35?
Excellent video!
@23:00 I just use the inverse of the adjustment factors and multiply. 1/0.71=1.408; 1/0.8= 1.25.
For a 50A circuit we will need 50 x 1.408 x 1.25 = we need a conductor rated for 88A.
From Table 310.15 B 16 #4 AWG is rated for 95 A which is slightly more than the required 88A.
My program has been failing at helping me comprehend this section for over 5 month. You helped me get it in a day before final exam of graduation.
Watching and grasping the whole concept before i program it on the excel lol 😅
Ahh so you are the electrical engineer who makes all my plans at work
Why is the ambient temperature correction always based on the 90C rating? Is there a code section that says to do that?
Wish you would have clearly said the answer to the last question is it #4 because its over 45 Amps or is it number 6 because its not over 50
What about the exception if there not simultaneously energized you don’t have to derate for conduit fill
I'm following along, taking notes, teaching myself, but this shit is hard to nail down.
It can take a while to learn, but keep up the practice! Hope the videos help!
Thanks from the Bluegrass
is this 2023 nec? the only issue i’m having studying is these temp factors. the guy who made the exam buster sent me a nasty email when i asked him a question. so here i am trying to self teach
still a fan...thank you
If the question is asking you to derate based only on the temperature (above 86 degrees F), do you still always start with the ampacity from the 90 degree column? Are there any instances that you "start a math problem" using the ampacities from the 75 or 60 degree rated columns? obviously it changes your answer if you start with the ampacity from the wrong column.
great question , I dont want to answer for him . I believe all adjustments happen starting in the 90 col.
240.4 (D1 - D7).
Does that state that were not allowed to upsize overcurrent device to the next standard size for conductors 10ga. or less ?
Hi, just followed you, may I know your reference book, and ask if it is available in the Philippines?
Hi, the book being referenced in this video is NFPA 70: The national electrical code, 2022 edition. I am not sure how ordering things online/shipping works in the Philippines, but the book is available on NFPA's website. Hope that helps!
on the last question where you gave 50 amp , 6 ccc and 140 degree. I started in the 90 degree col with a #8. You did something different and i dont understand why?
i think he was showing that there are correction factors and adjustments factors that will not change, so if you are a bit lost you could put in different ampacities using the same math till you find a answer on the test......im not 100% sure but i had the same problem as you can that was my best guess. Did you end up with 31.24 and next size up of 35?
nice