The Direct Answer: 2 HP 230V Single-Phase Motor FLA
According to NEC Table 430.248, the Full-Load Current (FLA) for a 2 HP, 230V, single-phase AC motor is 12 Amps.
This 12A value is the statutory baseline used by the National Electrical Code (NFPA 70) for sizing branch circuit conductors, short-circuit protection, and ground-fault protection. It is critical to understand that this table value is a code-mandated minimum baseline, not necessarily the exact physical current your specific motor will draw under load. For thermal overload sizing, you must always use the actual amperage printed on the motor's physical nameplate.
Always use the 230V column in Table 430.248 for standard residential and light-commercial 240V nominal systems. The NEC uses 230V as the reference baseline for calculations, even though your multimeter will likely read between 236V and 244V at the panel.
How to Read NEC Table 430.248 (Full-Load Currents)
Table 430.248, titled Full-Load Currents in Amperes, Single-Phase Alternating-Current Motors, is published in Article 430 of the NFPA 70 National Electrical Code. Here is how to properly parse the table for your installation:
- Voltage Columns: The table provides columns for 115V, 200V, 208V, and 230V. Match your nominal supply voltage. If you are on a standard US split-phase residential panel, use 230V.
- Horsepower Rows: Locate your motor's rated HP on the left-hand margin. Do not interpolate between rows; if your motor is 2 HP, use the exact 2 HP row.
- Temperature Rating Context: Table 430.248 gives you the current (12A). To find the wire size, you must take this current, multiply it by 125% (per NEC 430.22), and then look up the resulting ampacity in Table 310.16. Unless your equipment terminals are rated for 75°C, you must use the 60°C column of Table 310.16 for circuits under 100A.
Complete Reference: Single-Phase AC Motor FLA Chart
Below is the complete, unabridged data for standard single-phase AC motors from 1/2 HP to 10 HP. Bookmark this section for quick jobsite lookups. The 2 HP @ 230V row is highlighted as your target query.
| Motor HP | 115V (Amps) | 200V (Amps) | 208V (Amps) | 230V (Amps) |
|---|---|---|---|---|
| 1/2 | 9.8 | 5.6 | 5.4 | 4.9 |
| 3/4 | 13.8 | 7.9 | 7.6 | 6.9 |
| 1 | 16 | 9.2 | 8.8 | 8 |
| 1.5 | 20 | 11.5 | 11 | 10 |
| 2 | 24 | 13.8 | 13.2 | 12 |
| 3 | 34 | 19.6 | 18.7 | 17 |
| 5 | 56 | 32.2 | 30.8 | 28 |
| 7.5 | 80 | 46 | 44 | 40 |
| 10 | 100 | 57.5 | 55 | 50 |
Decision Path: Sizing Breakers and Wire for Your 2 HP Motor
Sizing motor circuits requires a different decision framework than standard resistive loads (like lighting or heaters). Motor starting currents (Locked Rotor Amps) are massive, meaning your short-circuit protection must be large enough to allow the motor to start without tripping, while your wire must be sized to handle continuous running heat. Use this EC&M motor calculation guide as a secondary reference for complex setups.
| Component | NEC Rule | Calculation | Concrete Pick |
|---|---|---|---|
| Branch Conductors | 430.22 (125% of FLA) | 12A × 1.25 = 15A minimum ampacity. | 12 AWG THHN/THWN-2 (25A @ 90°C, derated to 20A @ 60°C column for voltage drop margin). |
| Short-Circuit Breaker | 430.52 (Inverse Time, 250% max) | 12A × 2.50 = 30A maximum. | 30A 2-Pole Breaker (Standard inverse-time). |
| Disconnect Switch | 430.109 / 430.110 | Must be rated ≥ 115% of FLA (13.8A) and HP rated. | 30A 600V Fused/Non-Fused Disconnect (Must have a 2 HP rating stamped on it). |
While 14 AWG copper has a base ampacity of 15A (which technically meets the 15A minimum conductor calculation), NEC 240.4(D) strictly limits 14 AWG overcurrent protection to 15A. Because motor rules (430.52) allow a 30A breaker to protect the branch circuit, using 14 AWG wire on a 30A breaker violates code and creates a fire hazard. You must step up to 12 AWG minimum to legally pair the wire with the required 30A motor breaker.
What Table 430.248 Cannot Tell You (Nameplate vs. Code)
A common point of failure for junior electricians and DIYers is assuming Table 430.248 provides the final word on all motor sizing. It does not. Here is what the table cannot tell you, and how to handle the missing data:
1. Thermal Overload Heater Sizing
Table 430.248 is never used to size thermal overloads. Overloads protect the motor itself from burning out due to mechanical binding or phase loss. Per NEC 430.32, overloads must be sized based on the motor nameplate FLA and the motor's Service Factor (SF). If your 2 HP motor nameplate says 11.2A with a 1.15 SF, you size the overload at 125% of 11.2A (14A), completely ignoring the table's 12A value.
2. How Derating Modifies the Base Value
There is a persistent myth that ambient temperature derating (NEC Table 310.15) alters the 12A FLA found in Table 430.248. It does not. Derating factors modify the allowable ampacity of the conductor you selected from Table 310.16, not the load current. If you run your 12 AWG THHN through a 120°F attic, the wire's ampacity drops from 30A to 26.1A (using the 90°C column for derating). Since 26.1A is still well above your 15A minimum required conductor ampacity (12A × 1.25), your 12 AWG wire remains code-compliant. The 12A FLA remains static.
3. Locked Rotor Amps (LRA)
Table 430.248 only provides Full-Load running current. It will not tell you the momentary inrush current when the motor starts. For a standard capacitor-start induction motor, LRA is typically 5 to 7 times the FLA. If your 2 HP motor is on a weak grid or a long wire run, this massive voltage dip during startup can brownout sensitive electronics on the same panel. Calculate voltage drop based on LRA for runs exceeding 75 feet.
Final Sizing Recommendations for a 2 HP 230V Setup
To terminate the decision path, here is the exact, code-compliant Bill of Materials (BOM) for wiring a standard 2 HP, 230V, single-phase motor (like a Baldor-Reliance L1410T or equivalent) in a typical residential workshop environment:
- Wire: 12 AWG THHN/THWN-2 (Black, Red, Green). Run in 1/2-inch EMT or PVC conduit. If using NM-B (Romex), use 12/2 with ground, but note that NM-B is restricted to dry, indoor locations.
- Breaker: 30-Amp, 2-Pole, 240V Inverse-Time Thermal-Magnetic Breaker (Square D HOM230 or QO230, depending on your panel brand). If this is for an HVAC compressor, ensure the breaker is HACR rated.
- Disconnect: 30A, 240V, 2-Pole heavy-duty safety switch mounted within sight of the motor (NEC 430.102).
- Overload Protection: Set the adjustable dial on your motor starter to the exact FLA printed on the physical motor nameplate (usually between 10.5A and 11.5A for modern high-efficiency 2 HP motors).
By anchoring your wire and breaker sizing to the 12A baseline in NEC Table 430.248, while reserving the nameplate data strictly for thermal overload calibration, you ensure both code compliance and the physical survival of your equipment.
