kWから ボルト 計算機
電力消費量と最大電流がわかれば、必要な電圧レベルを求めることができます。配電計画やトランス設定に不可欠です。
電圧の算出
電力 + 電流 → 電圧
目標電力を供給するために必要な電位差です。
変換式
電圧計算は回路の種類によって異なります。相数と力率が計算を大きく変えます。
直流システム
V = (kW × 1000) ÷ I 電力を電流で割ったシンプルな計算です。バッテリーバンク、ソーラーアレイ、直流回路に使用されます。
単相AC
V = (kW × 1000) ÷ (I × PF) 住宅および軽商業用の標準です。力率はモーターなどの無効負荷を考慮します。
三相AC
V = (kW × 1000) ÷ (√3 × I × PF) 産業標準です。すべての三相線間電圧計算には√3（1.732）係数が必要です。
How to Convert kW to Volts
Calculating voltage from power and current is a fundamental electrical task — useful when verifying system design, checking nameplate data, or troubleshooting circuits. Because voltage, current, and power are linked by Ohm's Law and power equations, you need to know both the power in kilowatts and the current in amps to solve for voltage.
Key Takeaway
Higher voltage at the same power means less current flows. This is why transmission lines run at hundreds of thousands of volts — thin wires can carry enormous power with minimal resistive loss when current is kept low.
Step-by-Step Conversion Guide
- Identify the Power: Read the kW rating from your device or system specification sheet.
- Find the Current: Locate the ampere rating on the equipment nameplate or measure it with a clamp meter.
- Determine Circuit Type: Is it DC, single-phase AC (residential), or three-phase AC (industrial)?
- Apply the Power Factor: For AC circuits, locate the power factor (PF) on the nameplate — typically 0.8–0.95 for motors and 1.0 for purely resistive loads.
- Calculate: Divide (kW × 1000) by the appropriate denominator based on your circuit type.
Common System Voltages
- 12V / 24V / 48V: DC systems — automotive, solar, telecom, and battery storage.
- 120V / 240V: North American residential single-phase AC (split-phase).
- 208V / 480V: US commercial and industrial three-phase AC.
- 230V / 400V: European and international single-phase and three-phase standards.