Enter the width (mm), the thickness (mm), and the material carry capacity factor (amps/mm^2) into the calculator to determine the Busbar Current. 

Busbar Current Formula

The following formula is used to calculate the Busbar Current.

Ibb = w*t * MF
  • Where Ibb is the Busbar Current (amps)
  • w is the width (mm) 
  • t is the thickness (mm) 
  • MF is the material carry capacity factor (amps/mm^2)
    • 1.2 for copper
    • .8 for aluminum
    • .6 for iron
    • 1.6 for silver

To calculate a busbar current, multiply the width and thickness together, then multiply again by the material carry capacity factor.

How to Calculate Busbar Current?

The following example problems outline how to calculate Busbar Current.

Example Problem #1

  1. First, determine the width (mm). In this example, the width (mm) is determined to be 40 .
  2. Next, determine the thickness (mm). For this problem, the thickness (mm) is measured to be 10 .
  3. Next, determine the material carry capacity factor (amps/mm^2). In this case, the material carry capacity factor (amps/mm^2) is found to be 1.2.
    1. Finally, calculate the Busbar Current using the formula above: 

Ibb = w*t * MF

Inserting the values from above and solving yields: 

Ibb = 40*10 *1.2 = 480 (amps)

Example Problem #2

Using the same method as above, determine the variables required by the formula. For this example problem, these are:

width (mm) = 5

thickness (mm) = 3

material carry capacity factor (amps/mm^2) = .6

Enter these given values into the calculator or above yields: 

Ibb = 5*3 * .6 = 9 (amps)