Amp to Watt Converter

Formula depends on circuit type: DC or AC single-phase: Watts = Amps × Volts. Example: 10A × 120V = 1200W. AC three-phase: Watts = √3 × Amps × Volts × Power Factor. Example: 10A × 240V × 1.732 × 0.9 = 3,741W. Power factor: Typically 0.8-1.0 for resistive loads. Lower for inductive loads (motors). Common voltages: 120V (US household). 240V (US large appliances, Europe). 12V/24V (automotive, solar). Key: Need voltage to convert amps to watts. Reverse: Amps = Watts ÷ Volts (DC/single-phase). Why: Amps measure current flow, watts measure power consumption.

Electrical units explained: Amps (A): Current - flow rate of electricity. Like water flow through pipe. Determines wire size needed. Volts (V): Voltage - electrical pressure. Like water pressure. Determines shock hazard level. Watts (W): Power - actual energy consumption. Amps × Volts = Watts. What you pay for on electric bill. Analogy: Water hose. Amps = gallons per minute flowing. Volts = water pressure (PSI). Watts = work done (watering lawn). Example: 10A × 120V = 1200W space heater. Same power: 5A × 240V = 1200W also. Circuit capacity: 15A breaker at 120V = 1800W max. 20A breaker = 2400W max. Use 80% max continuous (1440W, 1920W).

15-amp circuit capacity: Maximum: 15A × 120V = 1,800 watts. Safe continuous load: 1,800W × 80% = 1,440 watts. NEC (National Electrical Code) requires 80% rule for continuous loads (3+ hours). Example loads: Microwave (1000-1500W) + coffee maker (800W) = 1800-2300W → Overload! Hair dryer (1500W) OK alone, not with other devices. LED lights (100W total) + TV (200W) + laptop (100W) = 400W → Safe. Tips: Don't run multiple high-wattage appliances on same circuit. Kitchen should have multiple 20A circuits. Check breaker panel for circuit ratings. Consequences of overload: Breaker trips (safety feature). Repeated overload damages wiring. Fire hazard if breaker fails. Upgrade: Install 20A circuit (2,400W max, 1,920W continuous) for high-power needs.

Power factor explained: Definition: Ratio of real power (watts) to apparent power (volt-amps). Range: 0 to 1.0 (or 0% to 100%). Perfect PF = 1.0 means all power used efficiently. Resistive loads (PF ≈ 1.0): Heaters, incandescent bulbs, toasters. Watts = Volts × Amps (simple calculation). Inductive loads (PF < 1.0): Motors, transformers, fluorescent lights. PF typically 0.6-0.9. Draw more current for same wattage. Example: 1000W motor with PF 0.8. Apparent power = 1000W ÷ 0.8 = 1250 VA. Current draw = 1250VA ÷ 120V = 10.4A (not 8.3A!). When it matters: Commercial buildings (utility charges for low PF). Sizing generators, wiring, breakers. Home use: Usually assume PF = 1.0 for estimates. Industrial: Must account for PF correction.

240V amp calculation: Formula: Amps = Watts ÷ Volts. For 240V: Amps = Watts ÷ 240. Common 240V appliances: Electric dryer: 5,000W ÷ 240V = 20.8A (needs 30A circuit). Electric range: 12,000W ÷ 240V = 50A (needs 50A circuit). Central AC (3-ton): 3,600W ÷ 240V = 15A (needs 20A+ circuit). Water heater: 4,500W ÷ 240V = 18.75A (needs 20-30A circuit). EV charger (Level 2): 7,200W ÷ 240V = 30A (needs 40A circuit). Circuit sizing: Always size breaker 125% of continuous load. Example: 20.8A dryer needs 20.8 × 1.25 = 26A → use 30A breaker. Wire gauge: 30A circuit needs 10 AWG wire. 50A needs 6 AWG. Benefits of 240V: Half the current for same wattage. Smaller wire gauge OK. More efficient for high-power devices.

Solar system calculations: Yes, with considerations: DC systems (panels to battery): Watts = Amps × Volts (simple). Example: 10A × 12V = 120W panel. 100Ah battery × 12V = 1,200Wh capacity. Inverter calculations: Input (DC): Watts ÷ DC volts = DC amps. Example: 1000W ÷ 12V = 83.3A from battery. Output (AC): Watts ÷ AC volts = AC amps. Example: 1000W ÷ 120V = 8.3A AC. Account for efficiency: Inverter 85-95% efficient. 1000W output needs ~1100W input. Wire sizing critical: High DC currents need thick wires. 83A needs 2 AWG or larger for short runs. Voltage drop issues at low voltage. Common voltages: 12V (small systems, RVs). 24V (medium systems). 48V (large systems, better efficiency). Example: 3000W system. At 12V: 250A (huge wires!). At 48V: 62.5A (manageable 4-6 AWG).

Wire gauge (AWG) recommendations: 15A circuit (1,800W @ 120V): 14 AWG copper minimum. Good for lights, outlets. 20A circuit (2,400W @ 120V): 12 AWG copper required. Kitchen, bathroom, garage outlets. 30A circuit (7,200W @ 240V): 10 AWG copper. Electric dryer, AC units. 40A circuit (9,600W @ 240V): 8 AWG copper. Electric range, large AC. 50A circuit (12,000W @ 240V): 6 AWG copper. Large range, RV hookup. 60A circuit: 4 AWG copper. Sub-panels, heavy equipment. Distance matters: Long runs need larger wire. Voltage drop limits: 3% for branch circuits, 5% total. Example: 20A at 100ft needs 10 AWG (not 12). Aluminum wire: One size larger than copper. 20A needs 10 AWG aluminum. Less expensive but requires special connections. Always: Follow NEC codes. Consult electrician for major installations. Larger wire = safer, less voltage drop.