Transformer Fault Current Calculator

Fill in the below fields to calculate the transformer's secondary fault current.
CalculatorHow to useDefinitions

How to Use the Calculator

Available Fault Current = ((kVA x 1000) / Secondary Voltage) / (IZ / 100)
Single phase formula
Available Fault Current = ((kVA x 1000) / 1.732 / Secondary Voltage) / (IZ / 100)
Three phase formula


Below are the definitions for the different terms that this calculator uses
What is Voltage?

Electric potential, measured in volts (V), represents the amount of electrical potential energy per unit charge at a specific point in the circuit. Voltage is the driving force that causes electric charges to move within a circuit.

What is kVA?

kVA stands for kilovolt-ampere, which is a unit of apparent power in an electrical system. It measures the total power, both real and reactive, in an alternating current (AC) circuit. The symbol for kilovolt-ampere is "kVA."

What are Amps?

Amps, short for amperes, is a unit of electric current. It is a measure of the rate at which electric charges flow through a conductor in an electrical circuit.

What is a transformer?

A transformer is an electrical device that takes a given input voltage and changes it to a different output voltage. This change can either be an increase or a decrease in voltage. Learn What Transformers Are, and How They Work

What is Available Fault Current?

Available Fault Current in transformers is the maximum current that can flow in a power system in the event of a fault, such as a short circuit.

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Transformer kVA Calculator

If you found the above calculator helpful, please also check out our transformer kVA Calculator

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