Voltage Drop API
Cable voltage-drop and conductor-sizing maths as an API, computed locally and deterministically. The drop endpoint computes the voltage lost along a cable run from the current, the one-way run length, the conductor cross-section and the material: the conductor resistance R = ρ·L/A, the voltage drop Vd = k·I·R (k = 2 for single-phase, √3 for three-phase), the drop as a percentage of the supply and the voltage left at the load. The sizing endpoint works backwards: from an allowable percentage drop it returns the minimum conductor cross-section needed, A ≥ k·I·ρ·L/Vd_allow, rounds up to the next standard cable size (1.5, 2.5, 4, 6, 10, 16, 25 … mm²) and reports the actual drop at that size. The power endpoint computes the power dissipated as heat in the cable, P = N·I²·R (N = 2 or 3 current-carrying conductors), and the cable efficiency given a load power. Copper (ρ = 0.0172) and aluminium (ρ = 0.0282 Ω·mm²/m) are supported. Everything is computed locally and deterministically, so it is instant and private. Ideal for electrical-installation and panel-design tools, cable selection to wiring-regulation limits, solar, EV-charger and sub-main sizing, and electrical-engineering education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is cable voltage drop and sizing; for Ohm's law, reactance and resonance use an Ohm's-law API and for transformer ratios use a transformer API.
api.oanor.com/voltagedrop-api
