Fault Current Calculator (PFC)

An electrical prospective fault current calculator application for single and three phase electrical systems. Calculate for Voltage, Loop Impedance or PFC fault current.

Fault Current Calculator for iPhone and iPad is a fast, free tool for electricians, contractors, and engineers. Calculate Prospective Fault Current (PFC), Prospective Short-Circuit Current (PSCC), and Prospective Earth Fault Current (PEFC).

Enter any two known values - voltage, loop impedance (Zs/Ze), or fault current - and the app instantly calculates the third.

KEY FEATURES:

PSCC and PEFC calculations: Calculate prospective short-circuit current for L-N or L-L faults and prospective earth fault current for L-E faults.

Single-phase and three-phase support: Perform fault-current calculations for both system types.

Automatic calculations: Enter any two known values to auto calculate the third.

Loop-impedance calculator: Calculate Zs or Ze from voltage and prospective fault current.

Formula display: See the formula used for each calculation so you can understand and verify the result.

Works offline: Use the app in roof spaces, basements, plant rooms, and other locations without a signal.

Dark mode and light mode: Maintain a clear display in different site conditions.

16 languages: Fully translated for electricians worldwide (af, ar, de, es, en, fr, hi, id, it, ja, ko, nl, pl, pt, ru, zh).

Fast and free: A clean interface designed to deliver results without unnecessary steps.

DEFINITIONS: AIC (Ampere Interrupting Capacity), often written as kAIC for kilo-Amperes, is a specific rating for protective devices that open a circuit, such as circuit breakers and fuses.

SCCR (Short-Circuit Current Rating) is the maximum fault current that a complete piece of equipment or electrical assembly (like an industrial control panel, switchboard, or HVAC unit) can safely withstand without causing a hazard.

Electrical calculations should be independently verified before safety-critical work. Ensure the calculated prospective fault current does not exceed the protective device's rated breaking capacity.

For additional tools, upgrade to Electrical Tools & Reference, which includes calculators for kVA, Max Zs, cable sizing, and more.

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