Amps to Horsepower Calculator

How to Convert Amps to Horsepower

Converting amperes (amps) to horsepower is a common task in electrical engineering and motor applications. This process involves understanding the relationship between electrical current, voltage, power factor, efficiency, and mechanical power output.

Conversion Formula

The formula to convert amps to horsepower depends on whether the system is single-phase or three-phase:

Single-Phase:

\[HP = \frac{I \times V \times PF \times \eta}{745.7}\]

Three-Phase:

\[HP = \frac{I \times V \times PF \times \eta \times \sqrt{3}}{745.7}\]

Where:

• HP is the power in horsepower
• I is the current in amperes (A)
• V is the voltage in volts (V)
• PF is the power factor
• η is the efficiency
• 745.7 is the conversion factor from watts to horsepower

Calculation Steps

1. Determine if the system is single-phase or three-phase
2. Measure or obtain the current (I) in amperes
3. Identify the voltage (V) of the system
4. Determine the power factor (PF) of the system
5. Identify the efficiency (η) of the motor or system
6. Calculate the power in watts using the appropriate formula
7. Convert the power from watts to horsepower by dividing by 745.7

Example Calculation

Let's convert 20 amps to horsepower for a three-phase motor:

• Current (I): 20 A
• Voltage (V): 480 V
• Power Factor (PF): 0.85
• Efficiency (η): 0.92

1. Calculate power in watts: \[P = 20 \text{ A} \times 480 \text{ V} \times 0.85 \times 0.92 \times \sqrt{3} = 13,068.7 \text{ W}\]
2. Convert watts to horsepower: \[HP = \frac{13,068.7 \text{ W}}{745.7} = 17.5 \text{ HP}\]

Therefore, 20 amps in this three-phase system is equivalent to approximately 17.5 horsepower.

Conversion Visualization

This bar chart visually compares 20 A to its equivalent of 17.5 HP. The chart illustrates how electrical current (amps) relates to mechanical power output (horsepower) in this specific three-phase motor example.