Amps and electrical wiring, AWG - wire gauge, electrical formulas, motors and units

12 Volt 2% Wire Loss Chart

Maximum distance of various gauge two conductor copper wire

AWG - American Wire Gauge and Circular Mils

American Wire Gauge - AWG - and circular mils

AWG to square mm Wire Gauge Conversion

Convert American Wire Gauge (AWG) to square mm cross sectional area

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 Volts 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

Capacitance in Parallel and Serial Connections

Capacitors in parallel and series circuits


Capacitors and capacitance - charge and unit of charge

Capacitors - Energy Stored

Potential power and energy stored in capacitors

Circles within Rectangles

The maximum number of circles packed 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 sources and color irradiation

Colour Code for Fixed Resistors

Value and tolerance

Conductor Resistance

Resistance in plain copper wire conductor


Conductors and conductivity

Conduit Sizes

Electrical conduit trade sizes, max distance between supports

Converting Ampere between Single Phase and 3 Phase

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

Copper Wire Properties

Gage, circular mils, electrical resistance and weight

Coulomb's Law

The electric force acting on a point charge

Current Division

Current division circuit

Current ratings for installation

Cables for fixed installation within buildings A1, A2, B1 and B2

DIN VDE Standards

DIN VDE power installations

Electric Circuit Diagram Template

Use Google Drive to make online shareable electric circuit diagrams

Electric Motor Online Calculator

Calculate amps, hp and kVA

Electric Shock

Physiological effect of electric shock

Electric Wire 240 Volts Single-Phase, Length and Voltage Drop

Wire length versus wire size with max. 2% voltage drop

Electric Wire Cross-Section Formulas

Calculate 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

Temperature change when mass is electrical heated

Electrical Motor - Locked Rotor Indicating Code Letters

Locked rotor indicating code letters for electrical motors

Electrical Motor Efficiency

Calculating electric motor efficiency

Electrical Motors - Efficiency Ratings

NEMA - electrical motors 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, Torque and RPM

Horsepower vs. torque and motor velocity - rpm

Electrical Motors and Heat Loss

Heat gain from electrical motors to surroundings

Electrical Potential - e.m.f

Change in electrical potential between two points

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

Extension Cords

Size of extension cords - full load rating 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

Full-load Currents in DC Motors

Current - Amps - in 120 and 240 Volt DC motors

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 environmental protection - electrical enclosure - of electrical equipment


The Electro Magnetic Field - EMF - induced into a circuit

Inductance in Serial and Parallel Connections

Serial and parallel inductance

Induction Motors - Synchronous and Full Load Speed

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

Inductors - Energy Stored

Energy stored in magnetic fields

Kirchhoff's Laws

Kirchhoff's current and voltage laws

Letter and Digit Code for Resistors

Indicating value of resistors by letter and digit code

Lights - Installed Power

Installed light power in some common types of buildings and rooms

Maximum Current for Wire

Maximum current for copper and aluminum wire

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

The relationships between 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

Potential Divider

Output voltage from a potential divider

Power Factor Three-Phase Electrical Motors

Power Factor definition for three-phase electrical motors

Power Wiring Color Codes

Typical power wiring color codes

Power and Horsepower in Electrical Motors

Electrical motor power is rated in Horsepower or Watts

Rechargeable Batteries

Properties of rechargeable batteries and accumulators

Relative Permittivity - Dielectric Constant

Some common materials and relative permittivity

Resistance Wires

Electric resistance and temperature rise in Nickel-Chromium resistance wires

Resistance and Conductance

The reciprocal of electrical Resistance is called Conductance

Resistance and Resistivity

Electrical resistance and resistivity

Resistance in Serial and Parallel Connections

Resistors in parallel and serial conections

Resistivity of Soil

Types of soil and mean value of resistivity

Resistivity, Conductivity and Temperature Coefficients for some Common Materials

Resistivity, conductivity and temperature coefficients for some common materials as silver, gold, platinum, iron and more - Including a tutorial explanation of resistivity and conductivity

Resistors - Standard Values

Preferred number series for resistors

SWG - Standard Wire Gauge

Imperial Standard Wire Gauge 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

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 Larger Circles

A tool to estimate the number of smaller circles that fits in a larger circle - or how many pipes or wires that fits in a larger pipe

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

TYpes of NEMA Electrical Enclosures

Description of NEMA electrical enclosures types

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 used to describe and classify 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

Voltage Drop

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

Wire - Convert from Square mm to Diameter mm

Convert from square mm to diameter mm

Wire Gauges - Current Ratings

Common US wire gauges - AWG gauges and their current ratings

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