Transformer Efficiency Calculator
Calculate transformer efficiency.
Formula first
Overview
Transformer efficiency measures how effectively a transformer transfers electrical power from the primary circuit to the secondary circuit. It is defined as the ratio of the output power delivered to the load compared to the total input power absorbed from the source, accounting for internal energy losses like heat and flux leakage.
Symbols
Variables
eta = Efficiency, W = Output Power, W = Input Power
Apply it well
When To Use
When to use: Use this equation when evaluating the performance of electrical transformers under specific load conditions. It assumes a steady state where input and output power can be measured or calculated based on voltage and current, typically in a laboratory or industrial setting.
Why it matters: High efficiency is critical for minimizing energy waste in power distribution grids and preventing overheating in industrial equipment. Modern transformers often exceed 95% efficiency, which is essential for sustainable energy management and reducing the environmental footprint of electricity transmission.
Avoid these traps
Common Mistakes
- Using percent without converting to decimal.
- Swapping Pin and Pout.
One free problem
Practice Problem
A power transformer receives 5000 Watts of input power and delivers 4850 Watts to a load. Calculate the efficiency as a decimal.
Solve for:
Hint: Divide the output power by the total input power.
The full worked solution stays in the interactive walkthrough.
References
Sources
- Halliday, Resnick, Walker, Fundamentals of Physics
- Wikipedia: Transformer
- Halliday, Resnick, Walker Fundamentals of Physics, 10th ed.
- NIST Chemistry WebBook
- Chapman, S. J. (2012). Electric Machinery Fundamentals (5th ed.). McGraw-Hill Education.
- Halliday, D., Resnick, R., & Walker, J. (2014). Fundamentals of Physics (10th ed.). John Wiley & Sons.
- Wikipedia: Transformer (article title)
- OCR A-Level Physics A — Electromagnetism