philsoma
Member
- Location
- Brighton, Michigan
I was referring to the idea that the load should be no more than 80% of the cb rating.For the record, what 80% rule?
5 of the
I was referring to the idea that the load should be no more than 80% of the cb rating.For the record, what 80% rule?
Even if you went with the 48 amps setting #6 NM cable is not going to burn up. Code compliant no, real world compliant yes.You guys convinced me. I will go with the 50-amp setting on the EV charger, using 40amps.
I was referring to the idea that the load should be no more than 80% of the cb rating.
I used to get “ I have never heard of that”There are a few supply houses around here that suffer from the "If I never herd of it they must not make it I cant be bothered to look" plague.
You can get copper SE down to #8 from some manufacturers but its a large minimum order.
210.19(A) says minimum conductor ampacity is to be 100% of non continuous load plus 125% of continuous load. If you have 60C insulation then 125% of 48 amps is 60. A 6 AWG 60C conductor only has an ampacity of 55, you must use a larger conductor. If it were a non continuous load then the 6 AWG @ 60C would be ok.Yes, that's the part that makes no sense, as ampacity is a continuous rating. Minimum ampacity required for a 48A continuous load should be 48A.
Cheers, Wayne
Technically there is only a 125% rule. But if working things backward then 80 is the reciprocal of 125.For the record, what 80% rule?
Yes, that rule makes no sense, and should be deleted. 210.20, shown in post #24, suffices to avoid nuisance tripping of non-100% rated OCPD under continuous loads. And then 240.4 will give you the minimum ampacity of the conductor to be protected by the OCPD sized to 210.20.210.19(A) says minimum conductor ampacity is to be 100% of non continuous load plus 125% of continuous load.
Worst one was supplier in oregon not knowing mc used anything other than 2 screw romex connectors for over 3/4 inch mc.I used to get “ I have never heard of that”
When I knew what it was I needed
You can order 6 seu copper online or another option is 4 AL SE to an ac disconnect then copper 6 thhn in conduit to the copper
I used to get “ I have never heard of that”
When I knew what it was I needed
It goes like this for me:Worst one was supplier in oregon not knowing mc used anything other than 2 screw romex connectors for over 3/4 inch mc.
I usually show them that they can get it. This case in peticular the counter guy just didn't know it was in their system and I ended up showing they had hundreds in their system and they just needed to order from beavertonIt goes like this for me:
One of our guys says " I called every supply house cant find it they said its not made"
I call manufacturer they say "we distribute thru xyz factory rep and abc electric supply call them".
I call abc electric supply "oh they dont make that its not in our computer".
I call factory rep "oh yeah they are a factory order 3-weeks out you order thru abc".
Me "Can you explain this to abc? Would you hold on a sec while I get abc on the line?"
I call abc and conference them to factory rep.
Part gets ordered arrived 3 weeks later.
Only if you use a 60C wiring method or your equipment has 60C rated terminals. With a 75C wiring method and 75C rated terminals, #6 Cu suffices.so, nobody has said it yet, but , what we need to run for 48 amps EV charger circuits are # 4 wire copper conductors.
110.14(C) plus Table 310.16. The 60C ampacity of #6 Cu is 55A, while the 75C ampacity of #6 Cu is 65A.could you cite the code reference for that?
I always took 110.14(C) as being required to use 60C ratings for circuits lower than 100A and up to 1 AWG and the 75C ratings for circuits above 100A or larger than 1 AWG...110.14(C) plus Table 310.16. The 60C ampacity of #6 Cu is 55A, while the 75C ampacity of #6 Cu is 65A.
Cheers, Wayne
If the terminals and conductors are rated for 75° C even if 100 amps or less you can still use the 75° C ampacity. NM cable has it's own 60° C restriction due to 334.80. IMO 334.80 needs to be removed from the code as it serves no real purpose when the cable is constructed using 90° conductors.I always took 110.14(C) as being required to use 60C ratings for circuits lower than 100A and up to 1 AWG and the 75C ratings for circuits above 100A or larger than 1 AWG...