What is a Watt to Volt Calculator?
A Watt to Volt Calculator is one of the most useful conversion tools as it easily changes power in watts to voltage in volts in DC and AC electrical circuits. Such conversion is important to one using electronics, electrical systems, or energy management as it determines the appropriate voltage use for the safe working of devices. This calculator is based on simple formulas used to calculate voltage from power and current inputs, making it very helpful for any engineer or electrician or anyone into DIY work. Whether calculating voltage for home appliances, industrial equipment, or devices operated by a battery, it’ll help you in the process, and with this Watt to Volt Calculator, you will be able to manage your power much more accurately.
Watt to Volt and AC Formulas
Formula 1: Watt to Volt using Power (Watts)
To calculate voltage when current (I) and power (P) are known:
\[ V = \frac{P}{I} \]
Where:
- \(V\) = Voltage in volts
- \(P\) = Power in watts
- \(I\) = Current in amps
Formula 2: Watt to Volt using Resistance (Ohms)
To calculate voltage when current (I) and resistance (R) are known:
\[ V = I \times R \]
Where:
- \(V\) = Voltage in volts
- \(I\) = Current in amps
- \(R\) = Resistance in ohms
Example Calculation 1: Using Power
If the current is 5 amps and power is 100 watts:
\[ V = \frac{100}{5} = 20 \text{ volts} \]
Example Calculation 2: Using Resistance
If the current is 5 amps and resistance is 4 ohms:
\[ V = 5 \times 4 = 20 \text{ volts} \]
Formula 1: AC Voltage (Peak to RMS)
To calculate the RMS (Root Mean Square) voltage from the peak voltage (Vpeak):
\[ V_{RMS} = \frac{V_{peak}}{\sqrt{2}} \]
Where:
- \(V_{RMS}\) = RMS Voltage in volts
- \(V_{peak}\) = Peak Voltage in volts
Formula 2: AC Power in Single-Phase Circuits
To calculate power in a single-phase AC circuit:
\[ P = V_{RMS} \times I_{RMS} \times \cos(\theta) \]
Where:
- \(P\) = Power in watts
- \(V_{RMS}\) = RMS Voltage in volts
- \(I_{RMS}\) = RMS Current in amps
- \(\theta\) = Phase angle between current and voltage
Formula 3: AC Power in Three-Phase Circuits
To calculate power in a three-phase AC circuit:
\[ P = \sqrt{3} \times V_{L} \times I_{L} \times \cos(\theta) \]
Where:
- \(P\) = Power in watts
- \(V_{L}\) = Line Voltage in volts
- \(I_{L}\) = Line Current in amps
- \(\theta\) = Phase angle between current and voltage
Example Calculation 1: AC Voltage (Peak to RMS)
If the peak voltage is 10 volts, calculate the RMS voltage:
\[ V_{RMS} = \frac{10}{\sqrt{2}} = 7.07 \text{ volts} \]
Example Calculation 2: AC Power in Single-Phase
If the RMS voltage is 120 volts, RMS current is 5 amps, and the phase angle is 0 degrees (for purely resistive load):
\[ P = 120 \times 5 \times \cos(0^\circ) = 120 \times 5 = 600 \text{ watts} \]
Example Calculation 3: AC Power in Three-Phase
If the line voltage is 400 volts, line current is 10 amps, and the phase angle is 0 degrees (for purely resistive load):
\[ P = \sqrt{3} \times 400 \times 10 \times \cos(0^\circ) = 1.732 \times 400 \times 10 = 6930.4 \text{ watts} \]
How to Use the Watt to Volt Calculator
- Choose Circuit Type: Select if you’re working with DC or AC.
- Enter Power (Watts): Input the power value in watts, typically marked on the device.
- Enter Current (Amps): Input the current in amps, often specified or measured.
- For AC, Enter Power Factor (PF): For AC circuits, add the PF value (usually 1 for resistive loads).
- Click Calculate: Hit the calculate button to find the voltage.
- View Result: The calculator will display the voltage in volts based on your inputs.