| Voltage (kV) | Conductor Size (AWG) | Insulation Thickness (mils) | Cable Diameter (inches) | Weight (lb/1000ft) | | --- | --- | --- | --- | --- | | 5 | 2 | 175 | 1.04 | 425 | | 5 | 1/0 | 175 | 1.24 | 550 | | 5 | 2/0 | 175 | 1.44 | 700 | | 8 | 1/0 | 200 | 1.49 | 750 | | 8 | 2/0 | 200 | 1.74 | 950 | | 8 | 3/0 | 200 | 2.01 | 1200 | | 15 | 2/0 | 250 | 2.24 | 1400 | | 15 | 3/0 | 250 | 2.56 | 1800 | | 15 | 4/0 | 250 | 2.93 | 2300 |
Ampacity varies based on installation method (air, duct, or direct burial) and ambient temperature. Always consult the manufacturer's specific data sheet. Key Factors in Selecting Your Cable Size 1. Voltage Drop
Ensure the cable survives a fault.
| User | Usefulness | Caution | |------|------------|---------| | | ⭐⭐⭐⭐⭐ | Already knows derating factors | | Industrial Electrician | ⭐⭐⭐⭐ | Often forgets shield bonding impact | | Solar/BESS Designer | ⭐⭐⭐ | Must ensure chart includes DC vs. AC (MV AC is typical) | | HVAC Technician | ⭐⭐ | Likely to mistake MV for low voltage – dangerous |
If cables are bundled together or installed in areas with high ambient soil temperature, their ability to dissipate heat decreases. In these cases, you must apply , which effectively lower the allowable ampacity of the cable. Summary Checklist for Engineers medium voltage cable size chart
A good medium voltage cable size chart is not optional – it's the law (NEC Table 310.60 for MV). But a bad chart (just a list of sizes and ampacities) is worse than useless; it's a trap.
Calculate the continuous current (Amps). | Voltage (kV) | Conductor Size (AWG) |
This guide provides a comprehensive medium voltage cable size chart and explains the factors that dictate your selection. Understanding Medium Voltage Cable Ratings
Used when faults may take up to an hour to clear. This requires thicker insulation, which affects the overall cable diameter and conduit sizing. 4. Environment and Derating Voltage Drop Ensure the cable survives a fault