Energy / Solar / Backup
Energy cost, appliance use, EV charging, solar sizing, payback, batteries, inverters and UPS estimates.
SpecCalc Hub
Electrical calculators and references
Search grouped calculators, converters, diagrams and references. Results are informational estimates only and must be verified before real-world decisions.
Which calculator should I choose?
For cost questions, start with Electricity Cost (e.g. monthly bills) or Appliance Energy Cost (e.g. TVs, heaters). For backup time, use Battery Runtime (for DC batteries) or UPS Runtime (for AC electronics). For cable topics, use Voltage Drop or Wire Size Estimate as preliminary planning tools only.
Important starting points
Catalog groups
Cable & Wiring
Voltage drop, wire-size estimates, cable loss, maximum length and AWG conversion with professional verification notes.
Motors
Motor current, power, speed, slip and capacitor planning context.
Electronics & Pinouts
Ohm's Law, resistor, inductor and capacitor codes, voltage divider, LED resistor and connector pin references.
General Electrical
Power triangle, kW/kVA/kVAr, power factor and transformer reference calculations.
References
IP ratings, grounding systems, electrical symbols, units and connection diagrams.
Calculator catalog FAQ
Are results final engineering design?
No. Results are informational estimates and high-risk topics require qualified professional verification.
Are calculator inputs stored?
No account is required and calculation history is not saved server-side.
Recommended calculators
10CalculationliveLow riskPDFGraphics
Electricity Cost Calculator
Estimate electricity cost, kWh use and appliance running cost from power, runtime, tariff and currency.
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Appliance Energy Cost Calculator
Estimate appliance cost using quantity, rated power, duty cycle, runtime, and tariff.
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Solar Panel Size Calculator
Estimate PV watts and whole-panel count from daily energy, peak sun hours, system losses and solar coverage.
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Solar Payback Calculator
Estimate simple solar payback from system cost, incentives, generation, and rates.
CalculationliveMedium riskPDFGraphics
Battery Runtime Calculator
Estimate usable Wh and backup hours from Ah or Wh, voltage, battery count, depth of discharge, efficiency and load.
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Inverter Size Calculator
Estimate continuous and surge inverter size from load, surge, margin, and power factor.
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UPS Runtime Calculator
Estimate UPS runtime from battery configuration, load, efficiency, and usable capacity.
CalculationliveLow riskPDFGraphics
EV Home Charging Cost Calculator
Estimate EV charging energy, cost, and time from battery size, SOC, efficiency, tariff, and charger power.
CalculationliveMedium-high riskPDFGraphics
Voltage Drop Calculator
Estimate DC, single-phase and three-phase voltage drop, percent loss and load voltage from cable size, length, current and material in simplified PF=1 mode.
CalculationliveHigh riskPDFGraphics
Wire Size Estimate Calculator
Estimate conductor area from voltage drop only. This is not final cable selection.
Energy, solar and backup power
9CalculationliveLow riskPDFGraphics
Electricity Cost Calculator
Estimate electricity cost, kWh use and appliance running cost from power, runtime, tariff and currency.
CalculationliveLow riskPDFGraphics
Appliance Energy Cost Calculator
Estimate appliance cost using quantity, rated power, duty cycle, runtime, and tariff.
CalculationliveMedium riskPDFGraphics
Solar Panel Size Calculator
Estimate PV watts and whole-panel count from daily energy, peak sun hours, system losses and solar coverage.
CalculationliveMedium riskPDFGraphics
Solar Payback Calculator
Estimate simple solar payback from system cost, incentives, generation, and rates.
CalculationliveMedium riskPDFGraphics
Battery Runtime Calculator
Estimate usable Wh and backup hours from Ah or Wh, voltage, battery count, depth of discharge, efficiency and load.
CalculationliveMedium riskPDFGraphics
Inverter Size Calculator
Estimate continuous and surge inverter size from load, surge, margin, and power factor.
CalculationliveMedium riskPDFGraphics
UPS Runtime Calculator
Estimate UPS runtime from battery configuration, load, efficiency, and usable capacity.
CalculationliveLow riskPDFGraphics
EV Home Charging Cost Calculator
Estimate EV charging energy, cost, and time from battery size, SOC, efficiency, tariff, and charger power.
CalculationbetaMedium riskGraphics
VanLife Trip Planner Calculator
Estimate fuel, water, daily power needs, battery and solar context, plus the total road-trip budget before opening routes on VanLife.uz.
Cable and wiring
7CalculationliveMedium-high riskPDFGraphics
Voltage Drop Calculator
Estimate DC, single-phase and three-phase voltage drop, percent loss and load voltage from cable size, length, current and material in simplified PF=1 mode.
CalculationliveHigh riskPDFGraphics
Wire Size Estimate Calculator
Estimate conductor area from voltage drop only. This is not final cable selection.
CalculationbetaMedium-high riskGraphics
Maximum Cable Length Calculator
Estimate maximum circuit length from voltage-drop assumptions.
CalculationbetaHigh riskGraphics
Cable Ampacity Estimate
Preliminary ampacity context with installation and derating reminders.
CalculationbetaMedium-high riskGraphics
Conduit Fill / Pipe Diameter Estimate
Reference workflow for estimating conduit fill before professional verification.
ConversionliveLow riskGraphics
AWG to mm² Converter
Convert common AWG conductor sizes to diameter and approximate cross-section.
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Cable Loss Calculator
Estimate I²R cable loss using simplified conductor resistance assumptions.
Motors
6CalculationbetaMedium riskGraphics
Motor Current Estimate
Estimate motor current from power, voltage, efficiency and power factor assumptions.
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Three-Phase Motor Power Calculator
Reference calculation for three-phase real power from voltage, current and power factor.
CalculationbetaHigh riskGraphics
Motor Capacitor Estimate
Educational reference for three-phase motor on single-phase supply capacitor estimates.
CalculationliveLow riskGraphics
Motor Synchronous Speed Calculator
Calculate synchronous speed from frequency and pole count.
CalculationliveLow riskGraphics
Motor Slip Calculator
Estimate induction motor slip from synchronous and measured speed.
ConversionliveLow riskGraphics
kW to HP Converter
Convert kilowatts to mechanical horsepower and back.
Electronics and pinouts
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USB Pinout Reference
Simplified educational USB pinout reference.
ReferencereferenceLow riskGraphics
RJ45 T568A/B Pinout Reference
Original diagram for T568A and T568B pair order.
ReferencereferenceLow riskGraphics
HDMI Pinout Reference
HDMI connector signal group reference.
ReferencereferenceLow riskGraphics
DisplayPort Pinout Reference
DisplayPort connector reference.
ReferencereferenceLow riskGraphics
VGA Pinout Reference
VGA connector signal reference.
ReferencereferenceMedium riskGraphics
SATA/Molex Pinout Reference
PC power connector reference.
CalculationliveLow riskGraphics
Resistor Color Code Calculator
Decode common 4-band resistor color codes.
CalculationliveLow riskGraphics
Inductor Color Code Calculator
Reference decoder for common inductor bands.
CalculationliveLow riskGraphics
Capacitor Code Calculator
Decode common three-digit capacitor markings.
CalculationbetaMedium riskGraphics
LED Resistor Calculator
Estimate a series resistor for a simple LED circuit.
CalculationliveLow riskGraphics
Voltage Divider Calculator
Calculate ideal two-resistor voltage divider output.
ConversionbetaMedium riskGraphics
Star/Delta Resistance Conversion
Reference formulas for balanced star and delta resistance conversion.
General electrical
10CalculationliveLow riskGraphics
Ohm's Law Calculator
Calculate voltage, current, resistance and power relationships.
CalculationbetaMedium riskGraphics
Power Calculator DC / Single-phase / Three-phase
Reference formulas for common power relationships.
ConversionbetaMedium riskGraphics
kW / kVA / kVAr Converter
Reference relationships between active, apparent and reactive power.
CalculationbetaMedium-high riskGraphics
Power Factor Correction Calculator
Preliminary capacitor kVAr estimate for target power factor.
CalculationbetaHigh riskGraphics
Grounding Resistance Estimate
High-risk reference for grounding resistance concepts.
CalculationbetaHigh riskGraphics
Short-Circuit Current Estimate
High-risk reference for short-circuit estimation concepts.
CalculationbetaMedium-high riskGraphics
Transformer Primary/Secondary Calculator
Reference formulas for ideal transformer voltage, current and turns ratios.
CalculationbetaMedium-high riskGraphics
Reactive Power Compensation Calculator
Preliminary calculator for reactive power compensation and kVAr capacitor sizing.
ConversionliveLow riskGraphics
Lighting Unit Converter
Reference converter context for lumen, lux and area relationships.
ConversionliveLow riskGraphics
IP Rating Decoder
Decode the two main digits in common IP protection ratings.
References and standards
7ReferencereferenceLow riskGraphics
IP Protection Classes Reference
Reference overview of ingress protection rating structure.
ReferencereferenceHigh riskGraphics
Grounding System Types Reference
TN-C, TN-S, TN-C-S, TT and IT educational diagrams.
ReferencereferenceLow riskGraphics
Electrical Symbols IEC/ANSI Reference
Reference overview for common schematic symbols.
ReferencereferenceLow riskGraphics
AWG Conversion Table
Reference table for AWG diameter and approximate area.
ReferencereferenceHigh riskGraphics
Cable Color References
Country-dependent cable color reference with strict verification note.
ReferencereferenceLow riskGraphics
Electrical Units Reference
Plain-language reference for common electrical units.
ReferencereferenceMedium-high riskGraphics
Three-Phase Connection Diagrams
Original simplified star and delta connection diagrams.