Calculators
Grouped by topic. Each one shows its formula, a worked example, assumptions, limitations and references.
Power & current
Line current, kW, kVA and kVAr for single- and three-phase circuits.
- Three-Phase & Single-Phase Current CalculatorCalculate line current from kW, hp or kVA for three-phase (line-to-line or line-to-neutral) and single-phase supplies, with PF, efficiency and every step shown.
- kVA to kW Converter (and kVAr)Convert between kVA, kW and kVAr using power factor, solve the power triangle from any two values and get the matching line current.
Generators
Diesel genset sizing with motor starting, and fuel use at part load.
- Generator Sizing CalculatorSize a generator set from a load table: running kW/kVA, diversity, motor starting kVA by DOL, soft starter or VFD, margin, derating and a common kVA rating.
- Diesel Generator Fuel Consumption CalculatorEstimate diesel generator fuel use in L/h from load and specific fuel consumption with an editable part-load curve, plus daily use, tank runtime and cost.
Cables
Voltage drop with temperature-corrected resistance and a size solver.
Transformers & PF
Transformer loading and losses, capacitor banks for power factor.
- Transformer Loading & Efficiency CalculatorFind transformer percentage loading, full-load currents on both windings, copper loss scaled with load squared, total losses and efficiency at the actual load.
- Power Factor Correction Capacitor CalculatorCalculate capacitor kVAr to raise power factor, capacitance per phase for star and delta banks at 50 or 60 Hz, and the resulting line current reduction.
Batteries & solar
Battery runtime with Peukert, and off-grid PV array and bank sizing.
- Battery Runtime Calculator with PeukertEstimate battery bank runtime from Ah, voltage, depth of discharge and inverter efficiency, with an optional Peukert correction and a series/parallel bank builder.
- Off-Grid Solar PV System Sizing CalculatorSize an off-grid solar PV system: array kWp and panel count from daily energy and peak sun hours, battery Ah for days of autonomy, and charge controller current.