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Please help with wire sizing

Anteclansing

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Joined
Oct 29, 2023
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Nevada
Hello all,

I am in the process of obtaining a 10kw split phase 120v/240v hybrid inverter. I am going to run it in split phase to an electrical panel. I am planning to have 4x20amp breakers and outlet at 120v and 1x50amp 240v outlet. Before you kill me, I am obviously not going to pull all of those watts at once. I use the 1x50amp at 240v to charge my EV and when I do, I will turn off the other loads. I know 12 gauge wire is enough for the 120v, and I am probably going to run 1/0 awg from inverter to panel. My question is about the split phase 240v

1. I believe I will have 4 cables: 2 hot, neutral and ground. I am going to connect the two hot to the two legs of the panel and then neutral to neutral busbar and ground to ground bus bar. My question is how big should my wire be from the panel to an outlet to guarantee 50amp? Should my neutral be 2x of my hot or same size? Thanks in advance.
 
For the 50a outlet, yes. I think code will allow 10ga on the ground. All wires should be sized to the breaker.
 
NFPA 70 (NEC) Table 310.16 (link below) provides current carrying capacities of typical insulated conductors. Please be aware that the ambient temperature can result in derating if you are installing in a non-conditioned space. As an example a THHN insulated #8 AWG installed where it is exposed to temperatures of 105F or greater would only be rated at 47.85 amps (55 x .87).

https://media.distributordatasoluti...msOcal20(USA)oc_1_g_nec31016pdfClickHerea.pdf

Table 250.122 provides the minimum size of the grounding conductor based upon the breaker (OCPD) size.

https://www.accessengineeringlibrary.com/content/book/9780071800655/back-matter/appendix2
 
NFPA 70 (NEC) Table 310.16 (link below) provides current carrying capacities of typical insulated conductors. Please be aware that the ambient temperature can result in derating if you are installing in a non-conditioned space. As an example a THHN insulated #8 AWG installed where it is exposed to temperatures of 105F or greater would only be rated at 47.85 amps (55 x .87).

https://media.distributordatasoluti...msOcal20(USA)oc_1_g_nec31016pdfClickHerea.pdf

Table 250.122 provides the minimum size of the grounding conductor based upon the breaker (OCPD) size.

https://www.accessengineeringlibrary.com/content/book/9780071800655/back-matter/appendix2
I always forget about derating
 
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