Copper Loss Calculator

Tools - Pcbcupid - Simple and easy to use Copper Loss Calculator

Electric current passing through copper conductors causes resistance, which in turn produces heat and causes copper loss. This dissipation of heat is a loss of thermal energy, or energy.
The square of the current flowing through the conductor and the resistance of the copper material determine copper loss in a straight line.

The primary purpose of understanding copper loss is to assess the efficiency of electrical systems and devices.
By minimizing copper loss, engineers can optimize the design and operation of electrical equipment, improving energy efficiency and reducing operational costs.

Understanding Copper Loss:

A common occurrence in many electrical devices, such as transformers, motors, and light bulbs, is copper loss. For instance, when a light bulb is used, copper loss occurs when the current passing through it encounters a certain degree of resistance. Similarly, the resistance in the windings of a motor causes copper loss.

In certain instances, copper loss can be reduced by utilizing materials like aluminum or silver that have lower resistivity or by improving the electrical device’s design to lessen resistance. Nonetheless, because of its low cost and excellent conductivity, copper is still commonly utilized. 


  • Transformer Design
  • Motor and Generator Efficiency
  • Power Transmission
  • Electrical Distribution Systems

Joule’s first law, where a and c represent the current and b and d the resistance, indicates that the energy lost per second grows as the square of the current passing through the winding. This can be used to determine loss. Use the Transformer Copper Loss Calculator below to determine transformer ohmic loss. To get the answers for your calculation, just enter the required values.

Note : Don’t end with comma ( , )

Primary Winding Current (a)
Primary Winding Ohmic Resistance (b)
Secondary Winding Current (c)
Secondary Winding Ohmic Resistance (d)


\[l = (a^2 * b) + (c^2 * d)\]


  • l = Copper Loss
  • a = Primary Winding Current
  • b = Primary Winding Ohmic Resistance
  • c = Secondary Winding Current
  • d = Secondary Winding Ohmic Resistance

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