How to convert Amps into Watts?

To convert Amps (A) into Watts (W), you need to know the voltage (V) in the circuit.

The formula to convert Amps into Watts is:

Watts (W) = Volts (V) x Amps (A)

or

W = V x A

Examples:

1. Volts (V) = 120V, Amps (A) = 5A

Watts (W) = V x A

W = 120V x 5A = 600W

2. V = 240V, A = 2A

W = 240V x 2A = 480W

3. V = 12V, A = 10A

W = 12V x 10A = 120W

How Many Watts Are in an Amp?

The number of watts in an amp depends on the voltage.
Watts (W) are a unit of power, while amps (A) are a unit of current.
To find the watts, you need to know the voltage (V) and the current (I).

The formula is:

W = V x I

Examples:

1. If you have 1 amp of current at 120 volts, the power would be:

W = 120V x 1A = 120W

2. If we have 5 amps of current at 120 volts, then the power will be

W= 120V x 5A = 600W.

What is the Conversion for Single-Phase AC Circuits?

For single-phase AC circuits, the power formula is:

P = V × I × cos(φ)

Where:

P = Power in watts

V = Voltage in volts

I = Current in amps

cos(φ) = Power factor (typically 0.8-1.0)

Typical power factor values

For resistive loads (power factor = 1):

P = V × I

Example:

10A at 230V with PF = 0.9, then we have the following power:

W = 10 x 230 x 0.9 = 2070W .

What is the Conversion for Three-Phase AC Circuits?

For three-phase AC circuits, there are two formulas:

Using Line-to-Line Voltage:

W = √3 x VL x I × cos(φ)

Where:

W = power in watts (W)

VL = line-to-line voltage in volts (V)

I = current in amps (A)

cos(φ) = power factor

Example:

10A, 400V (line-to-line), PF = 0.85

W = √3 x 10 X 400 x 0.85 ≈ 5896W

Using Line-to-Neutral Voltage:

W = 3 x V x I × cos(φ)

Where:

W = power in watts (W)

VLN = line-to-neutral voltage in volts (V)

I = current in amps (A)

cos(φ) = power factor

Note: VL = √3 × VLN, so both formulas are equivalent.

Example:
10A, 230V (line-to-neutral), PF = 0.85
W = 3 x 10 x 230 x 0.85 = 5865W.

How to Convert Amps and Ohms to Watts?

You need to know the voltage to convert amps and ohms to watts.

You can use Ohm's Law to find the voltage:

V = I x R.

Where:

V = voltage in volts (V)

I = current in amps (A)

R = resistance in ohms (Ω)

Then, you can use the formula:

W = V x I or

W = I² × R or

W = V²/R

Example:

5A through a 10Ω resistor
W = 5² x 10 = 250W.

What are Amps, Volts, and Watts?

Amps, volts, and watts are units of measurement for electricity:

• Volts (V): Electric potential difference or "pressure" that pushes electrons through a circuit. Think of it like water pressure in a pipe.
• Amps (A): Electric current or the flow rate of electrons. Similar to the flow rate of water through a pipe.
• Watts (W): Electric power or the rate of energy consumption. It represents how much work electricity can do per unit time.

Relationship:
W = A x V (for DC or purely resistive AC)

What are AC and DC power systems?

DC (Direct Current)

Electrons flow in one constant direction from positive to negative, and the voltage remains constant over time. Examples of DC power systems include batteries, solar panels, and electronic devices. The power calculation is straightforward: P = V × I.

AC (Alternating Current)

Electrons periodically reverse direction, typically 50-60 times per second (50-60 Hz). The voltage alternates between positive and negative values. Used in household and industrial power systems because it's more efficient for long-distance transmission. Power calculations must account for the power factor due to the alternating nature.

AC's key advantage is that voltage can be easily stepped up or down using transformers, making it ideal for power distribution networks.

To easily spot the differences see this comparison table:

Amps to watts at 120V (AC)

Amps to watts at 12V (DC)