Motor Calculator is a practical electrical engineering tool for calculating motor current and selecting a suitable cable size for single-phase and three-phase motors.

Designed for electricians technicians engineers students and maintenance professionals the app provides fast calculations through a clear and easy-to-use interface.

KEY FEATURES

✓ Single-Phase Motor Calculator
Calculate motor current using:

I = P ÷ (V × PF × Efficiency)

✓ Three-Phase Motor Calculator
Calculate motor current using:

I = P ÷ (√3 × V × PF × Efficiency)

✓ Multiple Power Units
Enter motor power in:

• Kilowatts (kW)
• Horsepower (HP)

✓ Motor Efficiency and Power Factor
Include motor efficiency and power factor for more realistic current calculations.

✓ Smart Three-Phase Cable Sizing
The three-phase calculator selects a recommended cable while considering:

• Motor design current
• 125% motor sizing factor
• Copper or aluminium conductors
• PVC or XLPE insulation
• Installation in air or underground
• Ambient or soil temperature
• Underground cable burial depth
• Cable route length
• Maximum permitted voltage drop

✓ Automatic Voltage-Drop Optimization
If the initially selected cable exceeds the chosen voltage-drop limit the app automatically checks larger cable sizes and recommends a more suitable option.

✓ Detailed Calculation Results
View useful engineering information including:

• Calculated motor current
• Motor design current
• Combined derating factor
• Required cable ampacity
• Recommended cable cross-section
• Voltage drop in volts
• Voltage-drop percentage

✓ Formula Explanations
Use the Show formula option to view the equation symbol definitions and power-unit conversions for single-phase and three-phase motors.

✓ Cable Configuration Options

• Copper or aluminium
• PVC or XLPE insulation
• Air or ground installation

✓ Input Validation
Clear validation messages help identify missing or invalid motor data before calculation.

WHY USE MOTOR CALCULATOR?

• Fast and straightforward motor calculations
• Professional clean interface
• Useful for fieldwork and preliminary design
• Combines motor-current calculation and cable selection
• Helps compare installation conditions before choosing a cable
• Works with common electrical units and motor parameters

IMPORTANT ENGINEERING NOTE

Cable recommendations are intended as preliminary engineering guidance. Final cable selection must be verified according to the applicable local electrical regulations and project requirements.

Always consider protection settings starting current starting voltage drop short-circuit withstand grouping factors installation conditions soil properties harmonic content manufacturer data and any additional derating factors before installation.

Motor Calculator does not replace a complete electrical design or approval by a qualified electrical engineer.