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Nec Voltage Drop: copper
2/0 AWG to 400 kcmil
NEC Chapter 9 Table 8 wire resistance and reactance data — DC resistance, AC resistance, and reactance for copper and aluminum conductors in PVC and steel conduit
| conductor material | conductor size | ac reactance ohm per kft pvc (ohm/kft) | ac reactance ohm per kft steel (ohm/kft) | ac resistance ohm per kft pvc (ohm/kft) | ac resistance ohm per kft steel (ohm/kft) | area cmil (cmil) | dc resistance ohm per kft uncoated (ohm/kft) | nec table | standard | stranding |
|---|---|---|---|---|---|---|---|---|---|---|
| copper | 2/0 AWG | 0.043 | 0.054 | 0.1 | 0.1 | 133,100 | 0.0967 | chapter9 table8 | NEC Chapter 9 Table 8 | 19 |
| copper | 250 kcmil | 0.041 | 0.052 | 0.052 | 0.054 | 250,000 | 0.0515 | chapter9 table8 | NEC Chapter 9 Table 8 | 37 |
| copper | 3 AWG | 0.047 | 0.059 | 0.25 | 0.25 | 52,620 | 0.245 | chapter9 table8 | NEC Chapter 9 Table 8 | 7 |
| copper | 3/0 AWG | 0.042 | 0.052 | 0.077 | 0.079 | 167,800 | 0.0766 | chapter9 table8 | NEC Chapter 9 Table 8 | 19 |
| copper | 300 kcmil | 0.041 | 0.051 | 0.044 | 0.045 | 300,000 | 0.0429 | chapter9 table8 | NEC Chapter 9 Table 8 | 37 |
| copper | 350 kcmil | 0.04 | 0.05 | 0.038 | 0.039 | 350,000 | 0.0367 | chapter9 table8 | NEC Chapter 9 Table 8 | 37 |
| copper | 4 AWG | 0.048 | 0.06 | 0.31 | 0.31 | 41,740 | 0.308 | chapter9 table8 | NEC Chapter 9 Table 8 | 7 |
| copper | 4/0 AWG | 0.041 | 0.051 | 0.062 | 0.063 | 211,600 | 0.0608 | chapter9 table8 | NEC Chapter 9 Table 8 | 19 |
| copper | 400 kcmil | 0.04 | 0.049 | 0.033 | 0.035 | 400,000 | 0.0321 | chapter9 table8 | NEC Chapter 9 Table 8 | 37 |
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