Electrical & Solar Engineering Calculators
Free interactive sizing tools engineered according to WAPDA P-10 standards, NEPRA net-metering regulations, and IEEE power engineering formulas. Select a calculator below to size your factory transformer, estimate commercial solar ROI, size capacitor banks, or calculate induction melting power.
Transformer kVA Sizing
Calculate standard 3-phase kVA from factory kW/Amps load.
Industrial Solar ROI
Calculate kW capacity, monthly savings, and payback period.
PFI Capacitor Bank
Calculate kVAR needed to eliminate DISCO low-PF penalty.
Induction Furnace MVA
Calculate crucible melting power & K-factor transformer MVA.
3-Phase Transformer kVA & Current Calculator.
Sizes distribution and power transformers for industrial facilities according to standard WAPDA/DISCO step ratings (25 kVA to 10 MVA) with 80% maximum continuous load buffer.
$$ ext{Required kVA} = rac{ ext{Connected kW}}{ ext{Power Factor}} imes (1 + ext{Safety Margin})$$ Operating transformers at continuous 100% capacity triggers overheating, dielectric oil breakdown, and premature insulation failure. TransfoLine recommends sizing units to run at 75%โ80% nominal load for maximum service life (25+ years).
Commercial & Industrial Solar ROI Calculator.
Estimates solar PV system capacity, monthly kilowatt-hour (kWh) generation, financial tariff savings, and capital payback period across Pakistan.
In Pakistan, 1 kWp of Tier-1 N-Type TopCon solar generates approximately 120 units (kWh) per month (1,440 kWh/yr) under local solar irradiance conditions. With commercial tariffs averaging PKR 52โ58/kWh, capital investment amortizes in 2.0 to 2.3 years, delivering 23+ years of free energy thereafter.
Power Factor (PFI) & Penalty Surcharge Calculator.
Calculates the exact capacitor bank capacity (kVAR) needed to improve factory power factor to 0.98, eliminating heavy DISCO low power factor surcharges.
$$ ext{Required kVAR} = P_{ ext{kW}} imes \left[ an(rccos( ext{PF}_1)) - an(rccos( ext{PF}_2)) ight]$$ Under NEPRA utility billing rules in Pakistan, when an industrial consumer's power factor drops below 0.90, the utility levies a severe monthly surcharge penalty. Installing an automatic PFI panel typically pays for itself within 3 to 5 months entirely from penalty elimination.
Induction Melting Furnace kVA & MVA Calculator.
Calculates active melting kilowatt (kW) requirements, furnace transformer MVA ratings, harmonic K-factor specifications, and forced cooling configurations for steel mills.
Induction furnaces generate high-order harmonics (5th, 7th, 11th, 13th) and severe electro-dynamic cyclic stresses during scrap cave-ins. TransfoLine manufactures heavy-duty furnace transformers with K-13 / K-20 rating, electrostatic Faraday shields, and Oil Forced Water Forced (OFWF) heat exchangers to prevent nuisance tripping and premature core burnouts.
Get a verified engineering quotation in 2 hours.
Send your calculated requirements or monthly electricity bill. Our senior electrical engineers will review your sizing parameters, verify voltage drop constraints, and deliver an itemized factory-direct proposal.