Topic

Power

PoE, UPS, batteries, generators and electrical protection.

Learn first

PoE Without Surprises PoE classes and standards (af/at/bt), how to budget your switch power, and why distance also charges in watts. ≈ 10 min read → Rack Power: UPS, Batteries & Generator How many minutes your UPS really lasts, how to size battery banks, and what generator you need when the outage drags on. ≈ 12 min read →

9 tools

PoE Budget

Calculate your devices' total draw and whether your switch can handle the load.

Voltage Drop

Calculate voltage drop (V and %) and the minimum AWG/mm² gauge for a given current, distance and voltage.

UPS Runtime

Estimate UPS backup minutes from load and batteries, and size the battery for a target runtime.

Three-Phase Power

Convert between kW, kVA, kVAR, current and power factor for single- and three-phase systems, and size with margin.

Load & Breaker

Size the circuit breaker for a load: convert VA/W to current (single or three phase), apply the 80% continuous-load rule and suggest the standard rating.

DC Battery Bank

Size a DC battery bank by autonomy: Ah capacity from load, voltage, depth of discharge, efficiency and temperature, plus the series/parallel array.

Conductor Ampacity

Compute a conductor maximum current by gauge and material, with temperature and grouping correction factors (NEC 310.16).

Generator Sizing

Size a genset from running load and motor starting peak, power factor and altitude/temperature derating.

Energy Cost & PUE

Compute a datacenter annual energy cost from IT power and PUE, the cooling overhead and CO₂ emissions.