40 hp motor: how many amps?
Full-load current from NEC Article 430 tables.
104 A
40 hp motor full-load current at 230 V three-phase · 29.84 kW output
Full-load current by voltage
| Supply | Full-load amps | Conductor ampacity (125%) |
|---|---|---|
| 208 V three-phase | 114 A | 142.5 A |
| 230 V three-phase | 104 A | 130.0 A |
| 460 V three-phase | 52.0 A | 65.0 A |
NEC 430.248/430.250 table values for typical induction motors; use these (not the nameplate) to size conductors and short-circuit protection, and the nameplate for overload protection.
FAQ
How many amps does a 40 hp motor draw?
Per NEC tables, 114 A A at 208 V three-phase; 104 A A at 230 V three-phase; 52.0 A A at 460 V three-phase.
How many watts is 40 hp?
40 hp = 29840 W of mechanical output. Electrical input is higher because of motor efficiency and power factor.