# Electrical Calculators

Voltage drop, three-phase power, power factor correction, transformer sizing, wire resistance, energy cost, AC impedance and battery banks.

## How to pay

Machine-payable over x402. USDC on: Base (eip155:8453), Solana (solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp), Polygon (eip155:137), Arbitrum One (eip155:42161).
No accounts. No API keys. No signup. The paying wallet is the account.

## Machine-readable

- OpenAPI: https://electrical-calc.x402tookit.com/openapi.json
- x402 manifest: https://electrical-calc.x402tookit.com/.well-known/x402
- Catalog (free): https://electrical-calc.x402tookit.com/catalog
- Health (free): https://electrical-calc.x402tookit.com/health
- Uptime (free): https://electrical-calc.x402tookit.com/uptime

## Endpoints (8)

### GET /battery-bank — $0.02
Battery bank layout (series and parallel counts) and runtime from load, voltage, Ah, depth of discharge and efficiency.
Params: loadW: number, systemVoltageV: number, batteryVoltageV: number, batteryAh: number, depthOfDischargePct?: number, efficiencyPct?: number, runtimeHours?: number, parallelStrings?: integer
Example: https://electrical-calc.x402tookit.com/battery-bank?loadW=500&systemVoltageV=24&batteryVoltageV=12&batteryAh=100&depthOfDischargePct=50&efficiencyPct=90&runtimeHours=5

### GET /energy-cost — $0.02
Energy use in kWh and its cost from a flat rate or tiered blocks, plus an optional demand charge and fixed fee.
Params: powerKw: number, hoursPerDay?: number, days?: number, kwh?: number, flatRatePerKwh?: number, tiers?: string, peakKw?: number, demandRatePerKw?: number, fixedCharge?: number
Example: https://electrical-calc.x402tookit.com/energy-cost?powerKw=2&hoursPerDay=5&days=30&tiers=100%3A0.10%3B100%3A0.15%3Binf%3A0.20&demandRatePerKw=8&fixedCharge=10

### GET /ohms-law-ac — $0.02
Series R, L, C impedance, phase angle, current, resonant frequency, Q and bandwidth at a given frequency.
Params: resistanceOhm: number, frequencyHz: number, inductanceMh?: number, capacitanceUf?: number, voltageV?: number
Example: https://electrical-calc.x402tookit.com/ohms-law-ac?resistanceOhm=10&inductanceMh=100&capacitanceUf=10&frequencyHz=159.155&voltageV=120

### GET /power-factor-correction — $0.02
Capacitor kVAR needed to raise power factor from one value to another, with new kVA and current and capacitance per phase.
Params: kw: number, pfFrom: number, pfTo: number, voltageV?: number, frequencyHz?: number
Example: https://electrical-calc.x402tookit.com/power-factor-correction?kw=100&pfFrom=0.8&pfTo=0.95&voltageV=400&frequencyHz=50

### GET /three-phase-power — $0.02
Balanced three-phase kW, kVA, kVAR and line and phase current from voltage, power factor and one of current, kW or kVA.
Params: voltageV: number, currentA?: number, kw?: number, kva?: number, powerFactor?: number
Example: https://electrical-calc.x402tookit.com/three-phase-power?voltageV=400&currentA=100&powerFactor=0.8

### GET /transformer-sizing — $0.02
Transformer kVA for a load with a stated margin, next common standard size, and primary and secondary full-load current.
Params: loadKw: number, secondaryVoltageV: number, powerFactor?: number, marginPct?: number, phase?: string, primaryVoltageV?: number
Example: https://electrical-calc.x402tookit.com/transformer-sizing?loadKw=80&powerFactor=0.8&marginPct=25&secondaryVoltageV=208&phase=three&primaryVoltageV=480

### GET /voltage-drop — $0.02
Voltage drop of a copper or aluminium conductor, single or three phase, by mm2 or AWG, length, current and temperature.
Params: material: string, currentA: number, lengthM: number, sizeMm2?: number, awg?: string, phase?: string, temperatureC?: number, supplyVoltageV?: number, powerFactor?: number, reactanceOhmPerKm?: number, limitPct?: number
Example: https://electrical-calc.x402tookit.com/voltage-drop?material=copper&currentA=20&lengthM=50&sizeMm2=10&phase=single&supplyVoltageV=230

### GET /wire-resistance — $0.02
Wire resistance R = rho L / A for copper or aluminium at a temperature, or correct a known resistance to a new temperature.
Params: material: string, lengthM?: number, sizeMm2?: number, awg?: string, temperatureC?: number, resistanceOhm?: number, fromTemperatureC?: number, toTemperatureC?: number
Example: https://electrical-calc.x402tookit.com/wire-resistance?material=copper&lengthM=100&sizeMm2=2.5&temperatureC=75

## Terms

Electrical arithmetic computed locally from the numbers given, using standard formulas, provided as is. Educational estimates only: not for design or code compliance. This shelf does not reproduce NEC or IEC ampacity tables; consult the applicable electrical code and a licensed electrician or engineer.