With the help of this Fault Current Calculator Excel form, you can rapidly estimate the fault current based on the MVA rating of the transformer and the secondary voltage.

**Excel Calculator**

This tool makes it simple to input transformer data and obtain fast results for your three-phase system. It also simplifies complex fault current calculations, which are otherwise difficult to perform.

**What is Fault Current?**

The fault current in transformers is the maximum current that can flow through a power system in the event of a failure, such as a short circuit.

**MVA Calculation**

The MVA (Mega Volt-Amperes) rating of a transformer indicates its apparent power capacity. To calculate a transformer’s MVA, apply the following formula:

**Formula**

**MVA = (KVA X 100)/(1000 X Z%)**

Where

KVA â€“ Transformer KVA Rating

Z% – Impedance %

**Fault Current Calculation**

To determine a transformer’s fault current using the MVA rating & secondary voltage, apply the following formula:

**Formula**

**I _{Fault }(KA) = (MVA X 10^{3})/ (âˆš3 X V_{Secondary})**

Where

I_{Fault }(KA) – Fault Current (in KA)

MVA – Transformer Rating

V_{Secondary} – Transformer Secondary Voltage

âˆš3 â€“ 1.732 â€“ 3 Phase System

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