VFD Calculator
Speed Control Results
Speed Calculations
Synchronous Speed:
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Estimated Actual Speed:
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Speed Ratio:
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Frequency Profile
Output Frequency:
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Base Frequency:
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Frequency/Base Ratio:
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Operating Region
Operating Region:
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Available Torque:
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Cooling Consideration:
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Speed-Torque Relationship
Constant Torque Region
Constant Power Region
Current Operating Point
V/Hz Profile Results
Output Voltage Calculation
Output Voltage:
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V/Hz Ratio:
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Voltage Percentage:
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Profile Information
Pattern Type:
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Boost Effect:
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Operation Mode:
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Motor Effects
Magnetization Level:
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Torque Capability:
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Recommendations:
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V/Hz Profile
Linear V/Hz
Selected V/Hz Profile
Operating Point
Acceleration/Deceleration Results
Time Calculations
Acceleration Time:
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Deceleration Time:
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Frequency Change:
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Current Requirements
Peak Current:
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VFD Loading:
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Limiting Factor:
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Recommendations
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Speed & Current Profile
Speed Profile
Current Profile
Power & Energy Results
Power Calculations
Fixed Speed Power:
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VFD Power:
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Power Savings:
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Annual Energy Calculations
Fixed Speed Energy:
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VFD Energy:
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Energy Savings:
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Annual Cost Calculations
Fixed Speed Cost:
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VFD Operating Cost:
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Annual Cost Savings:
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Power Consumption vs. Speed
Fixed Speed (On/Off Control)
VFD Speed Control
Operating Point(s)
VFD Sizing Results
VFD Rating Requirements
Recommended VFD Rating:
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Current Rating:
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Duty Rating:
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Derating Factors
Temperature Derating:
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Altitude Derating:
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Application Derating:
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Overall Derating Factor:
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Additional Requirements
Common VFD Ratings
| Power Rating | Common VFD Ratings | Common Overload Capacity |
|---|---|---|
| 1-10 HP / 0.75-7.5 kW | 1, 2, 3, 5, 7.5, 10 HP | 150% - 1 min |
| 10-50 HP / 7.5-37 kW | 10, 15, 20, 25, 30, 40, 50 HP | 150% - 1 min |
| 50-200 HP / 37-150 kW | 50, 60, 75, 100, 125, 150, 200 HP | 150% - 1 min or 110% - 1 min |
| 200+ HP / 150+ kW | 200, 250, 300, 350, 400, 500 HP | 110% - 1 min |
VFD Selection Guidelines
- Select VFD rating greater than or equal to motor power rating
- Consider a one-size larger VFD for high starting torque applications
- Industrial applications often require heavy-duty rated VFDs
- Consider harmonic mitigation for sensitive environments
- Long motor leads (>50m) may require output filters
- Dynamic braking is needed for rapid deceleration or regenerative loads
Generate a comprehensive report with all calculated parameters for documentation purposes
About Variable Frequency Drives
What is a VFD?
A Variable Frequency Drive (VFD) is an electronic device that controls AC motor speed by varying the frequency and voltage supplied to the motor. By adjusting the frequency, a VFD can control the motor's speed, which provides significant advantages in applications where speed control, energy efficiency, and process optimization are important.
Key Benefits
- Energy Savings: Reducing motor speed by just 20% can reduce energy consumption by up to 50%
- Improved Process Control: Precise speed control for optimal process performance
- Reduced Mechanical Stress: Soft start/stop capabilities reduce wear on mechanical components
- Lower Maintenance Costs: Less mechanical stress means fewer repairs
- Extended Equipment Life: Controlled acceleration and deceleration protect motor and driven equipment
Common VFD Applications
- Pumps: Match flow to actual demand, eliminate throttling losses
- Fans: Optimize airflow, replace damper control
- Compressors: Adjust capacity to match load requirements
- Conveyors: Soft start/stop and precise speed control
- HVAC Systems: Energy-efficient air handling and water circulation
- Process Control: Maintain precise control of production processes
- Machine Tools: Speed control for optimal cutting conditions
Important Parameters
- V/Hz Ratio: Maintains proper motor magnetization
- Acceleration/Deceleration Time: Affects motor stress and process performance
- Minimum/Maximum Frequency: Operating limits for the motor
- Carrier Frequency: Affects motor noise and heating
- Starting Torque: Determines ability to start under load