Everything, by category

Cross-section, diameter and nearest IEC 60228 size, generated from the AWG geometric definition.

Current, size adequacy for the size you specify, and running / starting voltage drop.

How current, size adequacy and voltage drop are screened.

Copper and aluminum DC resistance by temperature, Ω/km and Ω/kft, with mass per length.

Fill percentage from the conduit and conductor dimensions you enter.

Fill percentage from the dimensions you supply, against the limit for the number of conductors.

Longest run per conductor size for a given load and voltage drop limit.

Cable tray occupancy from tray width and cable diameters.

Occupancy of a cable tray by area and by width.

Amperes from kW, HP or kVA with voltage, phase, power factor and efficiency.

kW / HP / kVA to amperes for single- and three-phase systems at representative voltages.

Formulas and assumptions for converting power to current.

Solve kW, kVA, kVAR and power factor from any two values.

The power triangle relating kW, kVAR, kVA and power factor.

How percent loading and headroom are aggregated up the system.

US federal minimum efficiencies for general-purpose motors, 2016 and 2027 standards — public-domain values.

kVAR required to move from the present to a target power factor.

Capacitor sizing for a target power factor, and the cautions that come with it.

US federal minimum efficiencies for dry-type and liquid-immersed distribution transformers — public-domain values.

About thirty commonly used protective relay device numbers.

Functions commonly applied to transformers, motors, generators, buses and feeders, with IEEE guide pointers.

Common fuse, breaker and transformer kVA ratings.

Secondary fault current on an infinite bus or with a finite source impedance.

Per-unit estimate of bolted secondary fault current and its limits.

Running kW, largest motor starting kVA, transient voltage dip and step loading.

The PG1–PG3 method: running load, voltage dip on starting, instantaneous engine load.

Area for a target kW, or kW and annual energy for an area; fixed tilt or tracking; row spacing.

Winter-solstice row spacing, ground coverage ratio and the annual energy estimate.

Current requirement, anode count and life, and groundbed resistance for deep-well, vertical and horizontal beds.

Current, anode count and life, Dwight and Sunde groundbed resistance, rectifier rating.

Tolerable and calculated step and touch voltages for a substation grid (IEEE 80 method).

The IEEE Std 80 simplified equations, their range and what they leave out.

Estimated resistance using the Dwight / Sunde approximations.

Dwight formula and mutual resistance for rods in a line or ring.

Collection area, expected strike frequency and tolerable frequency (NFPA 780 / IEC 62305-2 methods).

Collection area and the expected versus tolerable strike frequency.

Ex d, e, i, nA, p, m, o, q, t — what each does and where it is typically used.

Class/Division and Zone systems side by side, gas groups and temperature classes explained.

How NEMA enclosure types relate to IP ratings, explained in our own words.

Heat from panels by type, rating and quantity, and the cooling it takes to remove it.

Loss models per equipment type, DOE transformer losses, BTU/hr, tons and ventilation airflow.

Average illuminance or luminaire count for a room.

Room cavity ratio, luminaire count, grid layout and spacing check.

Clear depth in front of electrical equipment by voltage and condition — federal public-domain values.

How the relative resilience index is built. Not an availability figure.

How single-outage scenarios are generated and evaluated.

The principle and formula behind temperature-correcting IR readings.

Correct a measured insulation resistance to a reference temperature.

Printable checklists for six equipment types with instrument classes and document pointers. No pass/fail values.

How checklist items, instrument classes and document pointers are assembled.

How close qualified workers may come to energized parts, 50 V to 800 kV, with altitude correction — federal public-domain values.

Searchable English–Korean electrical terminology.

HP/kW, ft/m, lb·ft/N·m, mil/mm and circular mils.

Engineering unit conversions.

Nominal system voltages and frequencies by country, with pointers to the governing standards.

Conductor identification colors by country and system.

Which standard and clause to consult for a given situation. Pointers only.