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SolarCalcKit HUB
SOLAR ENGINEERING INSTRUMENT SUITE

Size solar systems with engineering precision

SolarCalcKit delivers deterministic electrical sizing tools for solar professionals, contractors, and DIY engineers. Fully client-side, instant calculation engines, live SVG topological wiring diagrams, and transparent ledgers.

6 Modules
Complete Sizing Suite
100% Private
Client-Side Engine
SVG Topology
Live Wiring Diagrams
PDF Ready
Engineering Reports

Suite Modules

Engineering Calculators

Select an instrument to start sizing. All calculators re-render results live on input change with zero telemetry.

Flagship Tool v7 Engine

Solar Battery Sizing Instrument

Size your battery bank from daily energy use, autonomy days, system voltage, chemistry, and depth of discharge. Live SVG series/parallel wiring diagram and ledger breakdown.

E_nominal = (E_daily × Days) ÷ (η_inv × DoD)
Open Tool
Topology Engine v7 Engine

Battery Bank Wiring & Topology

Convert any target bank kWh or Ah into exact physical series and parallel strings, whole battery counts, and terminal wiring diagrams.

series = V_sys ÷ V_bat · strings = ⌈target Ah ÷ bat Ah⌉
Open Tool
NEC 690 Compliant v7 Engine

MPPT Charge Controller Sizer

Determine required continuous charging current from PV array wattage and battery voltage. Checks cold-temperature open-circuit voltage (Voc) against controller ratings.

I_out = P_array ÷ V_sys · Voc_cold = Voc × (1 + β·ΔT)
Open Tool
Ohmic Precision v7 Engine

Solar Wire Size & Voltage Drop

Size DC solar cabling from current, round-trip length, and allowable drop. Copper and aluminum conductor resistivity tables with standard AWG and mm² gauges.

Area = (2 × L × I × ρ) ÷ V_allowable_drop
Open Tool
Surge Sizing v7 Engine

Inverter Sizing & DC Current

Size inverters for combined continuous running wattage and motor startup surges. Computes DC battery current draw and fuse requirements.

P_cont = Σ P_load · I_dc = P_ac ÷ (V_sys × η)
Open Tool
Audit Utility v7 Engine

Solar Daily Load Calculator

Audit household electrical appliances to calculate total daily energy consumption (Wh & kWh/day) and connected instantaneous peak power.

Wh/day = Σ (Watts × Qty × Hours)
Open Tool

Compliance & Standards

Transparent Reference Methodology

Our algorithms follow internationally accepted engineering codes. We never use arbitrary multipliers or hidden safety factors.

IEEE 485

Recommended Practice for Sizing Lead-Acid & Lithium Batteries for Generating Stations

Provides standard cell voltage baselines, depth of discharge protection, and whole-string rounding rules.

NEC 690 / 706

National Electrical Code: Solar Photovoltaic & Energy Storage Systems

Mandates transparent conductor sizing, temperature-corrected open-circuit voltage checks, and disconnecting means.

IEC 60228 / 62548

Conductors of Insulated Cables & Design Requirements for PV Arrays

International resistance dataset for copper and aluminum conductors and MPPT voltage window safety thresholds.

OWNED & MAINTAINED BY RAXA TECHNOLOGY

About Raxa Technology

SolarCalcKit is engineered and maintained by Raxa Technology as a free, transparent, and 100% client-side solar engineering platform. We build deterministic modeling tools for solar installers, electrical contractors, off-grid engineers, and clean energy enthusiasts worldwide.

For inquiries, engineering feedback, partnership opportunities, or technical support, contact our team directly at: