3 hp motor: how many amps?
Full-load current from NEC Article 430 tables.
17 A
3 hp motor full-load current at 230 V single-phase · 2.24 kW output
Full-load current by voltage
| Supply | Full-load amps | Conductor ampacity (125%) |
|---|---|---|
| 115 V single-phase | 34 A | 42.5 A |
| 230 V single-phase | 17 A | 21.2 A |
| 208 V three-phase | 10.6 A | 13.2 A |
| 230 V three-phase | 9.6 A | 12.0 A |
| 460 V three-phase | 4.8 A | 6.0 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 3 hp motor draw?
Per NEC tables, 34 A A at 115 V single-phase; 17 A A at 230 V single-phase; 10.6 A A at 208 V three-phase; 9.6 A A at 230 V three-phase; 4.8 A A at 460 V three-phase.
How many watts is 3 hp?
3 hp = 2238 W of mechanical output. Electrical input is higher because of motor efficiency and power factor.