Electrical units, amps and electrical wiring, wire gauge and AWG, electrical formulas and motors

12 Volt Electric Wire - Length and Current

Maximum length of copper wire with 2% voltage drop

AC Circuit

An alternating current - AC - is generated by a sinusoidal voltage source

AWG - American Wire Gauge and Circular Mils

AWG, diameter mil, circular mil, diameter in mm and area in mm2

Active, Apparent and Reactive Power

Apparent, True Applied and Reactive Power - kVA

Amps and Wire Gauge - 12V Circuit

Maximum current - amps - through a 12V circuit - related to size (AWG) and length of wire

Asynchronous Motors - Electrical Data

Electrical motor data - nominal current, fuse, start ampere, contactor and circuit breaker of asynchronous motors

Automotive 12 Volt Electric Wiring

12 V current load and maximum wire lengths

CE Marking

The European Machine Directive

CM - Circular Mil Area

The circular mil area - CM - is a unit denoting the cross-sectional size of a wire or a cable


Capacitors and capacitance - charge and unit of charge

Capacitors - Energy Stored

Potential power and energy stored in capacitors

Capacitors - Parallel and Serial Connections

Capacitance in parallel and series connected circuits

Circles within Rectangles

The maximum number of circles it is possible to pack in a rectangle

Circuit Wiring - Single Phase (230V) Electrical Motors

Recommended copper wire gage and transformer size for single phase - 230 Volts - electrical motors

Circuit Wiring - Three Phase (230 & 460V) Electrical Motors

Recommended copper wire gage and transformer size for Three Phase - 230 & 460V - electrical motors

Color Temperatures

Light source and color irradiation


Conductors and conductivity - Electrical conductivity of some common materials

Conduits Sizes

Electrical conduits trade sizes and max distance between supports

Convert Ampere between Single Phase and 3 Phase

Convert amperage between single phase (120, 240 and 480 Voltage) and three phase (240 and 480 Voltage)

Copper Wire - Electrical Resistance

Electrical resistance in plain copper wire

Copper Wire Properties

Gage, circular mils, electrical resistance and weight

Coulomb's Law

Electric force acting on a point charge

Current Divider - Online Calculator

Electric current divider

DC Motors - Full-load Currents

Full load amps in 120 and 240 volts DC motors

DIN VDE Standards

DIN VDE power installations

Electric Cable Installations - Current Ratings

Current ratings and cable sizes for fixed installations within buildings

Electric Circuit Diagram - Template

Use Google Drive to make online shareable electric circuit diagrams

Electric Motor Calculator

Calculate amps, hp and kVA

Electric Shocks

Physiological effects of electric shocks

Electric Wire 240 Volts Single-Phase - Maximum Length

Maximum length of wire with 2% voltage drop

Electric Wires - Cross-Section Equations

Calculating single and bunched wire cross-sections and diameters

Electrical Formulas

The most common used electrical formulas - Ohms Law and combinations

Electrical Heating of a Mass

Electric heating of object and temperature change

Electrical Inductance - Serial and Parallel Connections

Serial and parallel inductance

Electrical Motor - Locked Rotor Indicating Code Letters

Locked rotor indicating code letters electrical motors

Electrical Motor Efficiency

Calculating electric motor efficiency

Electrical Motor Efficiency Ratings

NEMA - electrical motor efficiency ratings

Electrical Motors - Frame Sizes

NEMA electrical motor frame sizes

Electrical Motors - Full Load Currents

Full load currents for 460 volts, 230 volts and 115 volts motors - single and 3-phase

Electrical Motors - Insulation Classes

Temperature and insulation classes for electrical motors

Electrical Motors - Power and Torque vs. Speed

Speed of electrical motors - output power and torque

Electrical Motors and Heat Loss

Heat loss from an electrical motor to the surroundings

Electrical Resistance - Series and Parallel Networks

Resistors in parallel and serial connections

Electrical Units

Definition of common electrical units - like Ampere, Volt, Ohm, Siemens

Electrode Potential and Galvanic Corrosion

Introduction to electro chemical series and corrosion of metals

Electromotive Force - e.m.f

Change in electrical potential between two points

Extension Cords

Size of extension cords - full load ratings with 115 V

Frequency and Speed of Electrical Motors

The velocity of 2, 4, 6 and 8 poles electrical motors at 50 Hz and 60 Hz

IEC - NEMA Standard Torques

IEC and NEMA torque classifications of electrical motors

IEC Duty Cycles

The eight - S1 - S8 - IEC duty cycles of operating electrical motors

IP - Ingress Protection Rating

IP - Ingress Protection rating is used to specify the environmental protection - or electrical enclosure - of electrical equipment


Electro Magnetic Field - EMF - induced into a circuit

Induction Motors - Synchronous and Full Load Speed

Synchronous and full load speed of amplitude current (AC) induction motors

Inductors and Stored Energy

Energy stored in magnetic fields

Kirchhoff's Laws

Kirchhoff's current and voltage laws

Lights - Installed Power

Light power in common types of buildings and rooms

Luminous Efficacy

Light sources production of visible light

Motor Wiring Data - 480 Volt

Motor wiring data - NEMA Amps, Starter size, HMCP Size - motors ranging 1/2 - 500 HP

NEMA - National Electrical Manufacturers Association

National Electrical Manufacturers Association

NEMA A, B, C and D Electrical Motor Design

NEMA has established four different designs - A, B, C and D for electrical induction motors

NEMA Enclosure Standards of Electrical Motors

NEMA enclosure standard for electrical motors

NEMA Insulation Classes

Electrical insulation systems rated by standard NEMA classifications to maximize allowable operating temperatures

NEMA and IEC Enclosure Classifications

NEMA enclosure classifications versus IEC enclosure classifications

Nema Starters

Nema sized contactors or starters

Ohm's Law

Voltage, current and resistance

Online Wire Gauge - AWG - Calculator

Calculate AWG, mil, mm, CM or square mm

Parallel Circuits

Resistance, voltage and current in parallel networks


Electromagnetism and formation of magnetic fields

Potential Divider - Online Calculator

Output voltage from a potential divider

Power Factor Three-Phase Electrical Motors

Definition three-phase electrical motors power factor

Power Wiring - Color Codes

Color codes used in power wiring

Rechargeable Batteries - Battery Life Calculator

Properties of rechargeable batteries and accumulators

Relative Permittivity - the Dielectric Constant

Some common materials and their relative permittivity

Relative and Absolute Voltages

Electric circuit and voltage at any point

Resistance and Conductance

The reciprocal of electrical resistance is conductance

Resistance and Resistivity

Electrical resistance and resistivity

Resistivity and Conductivity - Temperature Coefficients for Common Materials

Resistivity, conductivity and temperature coefficients for some common materials as silver, gold, platinum, iron and more

Resistors - Color Codes Calculator

Color codes for fixed resistors - values and tolerances - online calculator

Resistors - Letters and Digit Codes

Letter and digit codes to indicating resistor values

Resistors - Standard Values

Preferred number series for resistors

SWG - Standard Wire Gauge

Imperial Standard Wire Gauge used for sheet metal and wire

Series Circuits

Voltage and current in series circuits

Service Factor

Service factor - SF - is a measure of periodically overload capacity at which a motor can operate without damaging

Shaft Power from Electrical Motors

Electrical motors are rated in horsepower or watt

Single Phase Power Equations

Single phase electrical power equations

Slip in Electrical Induction Motors

Difference between the synchronous and asynchronous speed - also named rated speed

Smaller Circles in a Larger Circle

Estimating number of smaller circles that fits in a larger circle - ex. how many pipes or wires fits in a larger pipe or conduit

Soil - Resistivity

Types of soil and their mean value of resistivities

Speed of Electrical Motors with operating Loads

Speed of an operating electrical motor with load is lower than the synchronous speed (no load) of the motor

Synchronous Speed of Electrical Motors

The speed at which an induction motor will operate depends on the input power frequency and the number of electrical magnetic poles in the motor

Three Phase Electrical Motors

Full load amps, wire and conduit sizes for three phase electrical motors

Three-Phase Power Equations

Electrical 3-phase equations

Torques in Electrical Induction Motors

Torques describes and classifies electrical motors


Alternating voltage and induced electro magnetic field - e.m.f. - in a transformer


A transient is a high voltage spike caused by an external or internal transient source

Types of NEMA Electrical Enclosures

Description of NEMA electrical enclosures types

Voltage Drop in Electric Circuit

Ohm's law and voltage drop in a current circuit

Voltage Imbalance - Derating Factor in Polyphase Motors

Efficiency of electrical polyphase motors decreases with increased voltage imbalance

Voltage by Country

Typical voltages and frequencies used for domestic appliances

Wire - Convert from Square mm to Diameter mm

Convert from square mm to diameter mm

Wire - Maximum Currents

Maximum currents in copper and aluminum wire

Wire Gauge Converter - AWG versus square mm

American Wire Gauge (AWG) versus square mm cross sectional area

Wire Gauges - Current Ratings

Common US wire gauges - AWG gauges and their current ratings

Wires - Electrical Resistance

Electric resistance and temperature rise in Nickel-Chromium wires

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