Enter the voltage (volts) and the resistance during short circuit (ohms) into the calculator to determine the Short Circuit Current. 

Short Circuit Current Formula

The following formula is used to calculate the Short Circuit Current. 

Ishort = V / Rshort
  • Where Ishort is the Short Circuit Current (amps)
  • V is the voltage (volts) 
  • Rshort is the resistance during short circuit (ohms) 

To calculate the short circuit current, divide the voltage by the resistance during the short.

A short circuit occurs when the resistance drops to a very low value.

How to Calculate Short Circuit Current?

The following two example problems outline how to calculate the Short Circuit Current.

Example Problem #1:

  1. First, determine the voltage (volts). In this example, the voltage (volts) is measured to be 500.
  2. Next, determine the resistance during short circuit (ohms). For this problem, the resistance during short circuit (ohms) is calculated to be .03.
  3. Finally, calculate the Short Circuit Current using the formula above: 

Ishort = V / Rshort

Inserting the values from above and solving the equation with the imputed values gives: 

Ishort = 500 / .03 = 16,666.66 (amps)


Example Problem #2: 

Using the same process as example problem 1, we first define the variables outlined by the formula. In this case, the values are:

voltage (volts) = 50

resistance during short circuit (ohms) = .25

Entering these values into the formula above gives : 

Ishort = 50 / .25 = 200 (amps)