Transformer Efficiency and Loss Calculator
Estimate transformer efficiency and annual energy loss from no-load loss, full-load copper loss, output power, and a load profile.
Enter nameplate or test values
Loss and efficiency estimate
About this calculator
Estimate transformer efficiency and annual energy loss from no-load loss, full-load copper loss, output power, and a load profile.
Assumes no-load loss stays constant and copper loss varies with the square of load fraction. This estimate does not certify regulatory efficiency or model varying load profiles hour by hour.
Method and assumptions
At load fraction x, total loss = no-load loss + full-load copper loss × x². Efficiency = output power ÷ (output power + losses) × 100. Annual loss energy multiplies total loss by entered operating hours and days; cost multiplies energy by the entered rate.
Enter manufacturer nameplate or test data for the exact transformer and operating condition. Default values are examples and should be replaced with project data.
FAQs
Does this provide wiring or switching instructions?
No. It estimates electrical quantities from entered values. Follow manufacturer diagrams, safe work procedures, and qualified design review for any equipment application.
Are these results equipment approval or certification?
No. Confirm ratings, test conditions, load profile, thermal limits, and applicable installation requirements independently.
Sources
Transformer nameplate or test data supplied by the user and the ideal relationships described above.