1. What is the 3 Phase HP to Amps Calculation?

The 3 Phase HP to Amps calculation determines the current drawn by a three-phase motor given its horsepower rating, voltage, power factor, and efficiency. This is essential for proper electrical system design and circuit protection.

2. How Does the Calculator Work?

The calculator uses the 3 phase formula:

Where:

• \( HP \) — Horsepower rating of the motor
• \( Volts \) — Line-to-line voltage
• \( PF \) — Power factor (typically 0.8-0.95)
• \( Efficiency \) — Motor efficiency (typically 0.8-0.95)
• 746 — Conversion factor from HP to watts
• √3 — Constant for three-phase systems (≈1.732)

Explanation: The equation converts mechanical horsepower to electrical power requirements, accounting for three-phase power characteristics and motor inefficiencies.

3. Importance of Current Calculation

Details: Accurate current calculation is crucial for selecting proper wire sizes, circuit breakers, and overload protection devices to ensure safe and efficient motor operation.

4. Using the Calculator

Tips: Enter HP rating, line voltage, power factor (typically 0.8 if unknown), and motor efficiency (typically 0.9 if unknown). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: Why multiply HP by 746?
A: 1 horsepower equals 746 watts, converting mechanical power to electrical power equivalent.

Q2: What is power factor?
A: Power factor is the ratio of real power to apparent power, representing phase difference between voltage and current.

Q3: How does voltage affect current?
A: Current is inversely proportional to voltage - higher voltage systems require less current for the same power.

Q4: What are typical efficiency values?
A: Standard motors typically have 85-95% efficiency, with higher efficiency in larger motors.

Q5: Is this calculation valid for single-phase motors?
A: No, single-phase motors use a different formula without the √3 factor.