swap_horiz Looking to convert 11.25A at 24V back to watts?

How Many Amps Is 270 Watts at 24V?

270 watts equals 11.25 amps at 24V on a DC circuit. On AC single-phase at PF 0.85 the same real power would be 13.24 amps.

At 11.25A, the NEC 210.19(A) continuous-load sizing math (125% of the load, equivalently 80% of the breaker rating) points to a 15A breaker as the smallest standard size that covers this load continuously.

270 watts at 24V
11.25 Amps
270 watts equals 11.25 amps at 24 volts (DC)
AC Single Phase (PF 0.85)13.24 A
11.25

Assumes a DC circuit. Typing a commercial L-L voltage (208/400/480V) re-routes the result to three-phase; 277V stays on single-phase because it's the L-N lighting leg of a 480Y/277V wye; 12/24V re-routes to DC.

Formulas

DC: Watts to Amps

I(A) = P(W) ÷ V(V)

270 ÷ 24 = 11.25 A

AC Single Phase (PF = 0.85)

I(A) = P(W) ÷ (PF × V(V))

270 ÷ (0.85 × 24) = 270 ÷ 20.4 = 13.24 A

Circuit Sizing

Breaker Sizing

NEC 240.6(A) standard ampere ratings for branch-circuit and feeder breakers start at 15, 20, 25, 30, 35, 40, 45, and 50A and continue at 60A and above for feeder and large-appliance circuits. At 11.25A, the smallest standard breaker the raw current fits under is 15A. NEC 210.19(A) sizes conductor and OCP at 125% of any continuous load, equivalently 80% of breaker rating. Final selection still depends on the equipment nameplate, whether the load is continuous, conductor ampacity, and local code.

Breaker SizeMax Continuous Load (80%)Status for 11.25A
15A12AOK for continuous
20A16AOK for continuous
25A20AOK for continuous
30A24AOK for continuous
35A28AOK for continuous
40A32AOK for continuous
45A36AOK for continuous
50A40AOK for continuous

Energy Cost

Running 270W costs approximately $0.05 per hour at the US average rate of $0.17/kWh (rates last reviewed April 2026). That is $0.37 for 8 hours or about $11.02 per month. See detailed cost breakdown.

AC Conversion Detail

The DC baseline for 270W at 24V is 11.25A. On an AC circuit with a power factor of 0.85, the current rises to 13.24A because reactive current flows alongside the real-power current.

Circuit TypeFormulaResult
DC270 ÷ 2411.25 A
AC Single Phase (PF 0.85)270 ÷ (24 × 0.85)13.24 A

Power Factor Reference

Power factor is the main reason 270W draws more current on AC than DC. At PF 1.0 (pure resistive, like a heater), the load pulls 11.25A at 24V on the single-phase basis the rest of the page uses. At PF 0.80 (typical induction motor), the same 270W pulls 14.06A. That is an extra 2.81A just to overcome the reactive component. Use the typical values below as a starting point, not for precise engineering calculations.

Load TypeTypical PF270W at 24V (single-phase)
Resistive (heaters, incandescent)111.25 A
Fluorescent lamps0.9511.84 A
LED lighting0.912.5 A
Synchronous motors0.912.5 A
Typical mixed loads0.8513.24 A
Induction motors (full load)0.814.06 A
Computers (without PFC)0.6517.31 A
Induction motors (no load)0.3532.14 A

Other Wattages at 24V

WattsDC AmpsAC 1Φ Amps PF 0.85
10W0.4167A0.4902A
15W0.625A0.7353A
20W0.8333A0.9804A
25W1.04A1.23A
30W1.25A1.47A
40W1.67A1.96A
50W2.08A2.45A
60W2.5A2.94A
75W3.13A3.68A
100W4.17A4.9A
120W5A5.88A
150W6.25A7.35A
200W8.33A9.8A
250W10.42A12.25A
300W12.5A14.71A
350W14.58A17.16A
400W16.67A19.61A
450W18.75A22.06A
500W20.83A24.51A
600W25A29.41A

Frequently Asked Questions

270W at 24V draws 11.25 amps on DC. For comparison at the same voltage: 11.25A on DC, 13.24A on AC single-phase at PF 0.85. Actual current depends on the load's power factor.
NEC 210.19(A) sizes the conductor and overcurrent device at not less than 125% of any continuous load (a load that runs three hours or more), equivalently 80% of the breaker rating. At 11.25A (the current the branch conductors actually carry on DC), the minimum breaker that satisfies this is 15A under typical assumptions. Brief non-continuous use can run closer to the full breaker rating, but space heaters, EV chargers, and long-running appliances should be sized for the continuous case.
For resistive loads (heaters, incandescent bulbs, electric kettles) use PF 1.0. For motors, use 0.80. For mixed office/residential use 0.85. For computers and LED arrays the effective PF can be 0.65 or lower. Power factor only applies to AC.
At the US residential average of $0.17/kWh (last reviewed April 2026), 270W costs $0.05 per hour and $0.37 for 8 hours. Rates vary by utility and time of day.
24V is not a standard household receptacle voltage in the US. It is used on commercial or industrial panels and typically feeds hardwired equipment or specialty twistlock receptacles, not plug-in appliances. Any 270W load at this voltage is a dedicated-circuit, nameplate-driven install, not a plug-in decision.
This calculator provides estimates for reference purposes only. Always consult a licensed electrician and verify compliance with the National Electrical Code (NEC) and local electrical codes before performing any electrical work.