NEC Motor Circuit Sizing Calculator (Article 430)

What size breaker and wire do I need for a 10 hp 460V three-phase motor?

Select three-phase AC, 460 V, and 10 hp; the calculator uses the FLC from NEC Table 430.250 rather than the nameplate, per 430.6(A)(1). Conductors are sized at a minimum 125% of FLC (430.22), the short-circuit/ground-fault OCPD is capped by Table 430.52 (for example 250% of FLC for an inverse-time breaker), and the disconnect is at least 115% of FLC (430.110). The tool rounds the OCPD up to the next standard size.

Related questions

• Why does the motor calculator use table FLC instead of the nameplate amps?
• Can I use this calculator for a VFD or HVAC compressor circuit?