All electrical calculators
Explore 22 engineering tools across 7 disciplines. Available calculators include worked equations and detailed mathematical explanations.
- Electrical Fundamentals · 2
- Cables & Distribution · 6
- Power Systems · 5
- Power Quality · 2
- Motors & Industrial · 3
- Protection & Safety · 3
- Renewable Energy · 1
Electrical Fundamentals · 2
Cables & Distribution · 6
Voltage Drop
Single-phase, three-phase and DC cable voltage drop with explained equations.
Cables & Distribution →LV Cable Sizing
Get a preliminary minimum Cu/Al cable recommendation from current, length, PVC/XLPE and installation method; compare parallel runs and explore the math.
Cables & Distribution →MV Cable Sizing
Preliminary Cu/Al XLPE sizing for directly buried and ducted 10–30 kV cables, with engineering assumptions and worked formulas.
Cables & Distribution →PE Conductor Sizing
IEC 60364-5-54 table, adiabatic check with k chosen for the conductor size and installation, and separate Cu/Al PE minimums.
Cables & Distribution →LV Busbar Sizing
Screen copper or aluminium rectangular busbar sizes from current or transformer kVA, with short-time conductor fault heating and clear IEC 61439 verification limits.
Cables & Distribution →Cable Tray Fill
Single-row width check from cable outside diameters.
Cables & Distribution →Power Systems · 5
LV Short-Circuit Current
Dynamic Main LV → DB1–DB5 radial fault network, auto cable R/X lookup, 3φ/2φ limits and breaker ratings (engineering screening).
Power Systems →Transformer Calculator
Three-phase cast-resin or oil-immersed transformer currents, winding quantities, Dyn5/Dyn11 vector groups, impedance and preliminary LV fault level.
Power Systems →Transformer Loss & Energy Cost
Annual transformer loss energy and energy cost from the no-load loss P0 and the load loss Pk (estimate).
Power Systems →Transformer Tap Adjustment
Predicted LV voltage at each MV tap, from a measurement.
Power Systems →UPS & Battery Sizing
UPS power in W and VA, and preliminary battery energy.
Power Systems →Power Quality · 2
Power Factor
Find power factor from kW, kvar or kVA, estimate reactive compensation and compare current before and after correction.
Power Quality →Reactive Components (C / L) — Capacitors & Reactors
Convert capacitor-bank or reactor kvar to C/L, calculate delta/star branch values, and estimate kvar from isolated L-L measurements.
Power Quality →Motors & Industrial · 3
Motor Current & Starting
Rated and delta winding current, and four starting-method figures.
Motors & Industrial →Soft Starter Sizing
In-line current to seek, assumed current limit and candidate checks.
Motors & Industrial →VFD Sizing
Required continuous output current and candidate checks.
Motors & Industrial →Protection & Safety · 3
CT & VT Sizing
Instrument-transformer ratios and burden screening, CT and VT tabs.
Protection & Safety →MV Transformer Protection Settings (50/51/50N/51N)
Reference pickups in ABB REF615 format; reference only, not for commissioning.
Protection & Safety →Insulation Resistance PI/DAR
Polarization index and dielectric absorption ratio.
Protection & Safety →