1/3 hp motor: how many amps?
Full-load current from NEC Article 430 tables.
3.6 A
1/3 hp motor full-load current at 230 V single-phase · 0.25 kW output
Full-load current by voltage
| Supply | Full-load amps | Conductor ampacity (125%) |
|---|---|---|
| 115 V single-phase | 7.2 A | 9.0 A |
| 230 V single-phase | 3.6 A | 4.5 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 1/3 hp motor draw?
Per NEC tables, 7.2 A A at 115 V single-phase; 3.6 A A at 230 V single-phase.
How many watts is 1/3 hp?
1/3 hp = 249 W of mechanical output. Electrical input is higher because of motor efficiency and power factor.